Browse by condition.

5-Alpha-Reductase Deficiency

5-alpha-reductase deficiency is a rare inherited condition that affects sexual development before birth and during puberty. People with the condition have one X and one Y chromosome and have testes, and they produce testosterone normally. What they cannot do normally is convert that testosterone into dihydrotestosterone (DHT), the more potent androgen that external genital development before birth depends on. The cause is a change in the SRD5A2 gene, which carries the instructions for the enzyme steroid 5-alpha reductase 2 — the enzyme that performs the conversion. Inheritance is autosomal recessive: both copies of the gene carry a variant, and parents who carry one altered copy typically have no signs of the condition themselves. Someone with two variant copies and two X chromosomes is not physically affected, because female development does not depend on DHT. How it presents Appearance at birth varies considerably. External genitalia may appear female, may be male-typical with a small penis and hypospadias, or may not look clearly male or female.

Acquired angioedema (AAE)

Acquired Angioedema (AAE): A Comprehensive Overview Acquired Angioedema (AAE) is a rare disorder characterized by recurrent episodes of swelling (angioedema) in the skin and mucous membranes. Unlike hereditary angioedema (HAE), AAE typically develops in adulthood, often after age 40 or 50, and is not inherited. It results from an acquired deficiency or dysfunction of the C1 esterase inhibitor (C1-INH), a protein essential for regulating the complement system and controlling inflammation. What Causes AAE? AAE is caused by excessive activity of bradykinin, a molecule that increases blood vessel permeability and causes swelling. In a healthy immune system, C1-INH controls bradykinin production. In AAE, this regulatory function fails due to very low C1-INH activity. There are two main subtypes of AAE: Type I AAE occurs when C1-INH is consumed at an abnormally high rate. This is often associated with lymphoproliferative disorders (such as lymphoma or chronic lymphocytic leukemia), autoimmune diseases, or certain solid tumors.

Acquired Hemophilia A

Acute cholecystitis

Acute cholecystitis is a severe condition that affects the gallbladder, an essential organ responsible for storing bile produced by the liver. This medical emergency arises when the gallbladder becomes inflamed, often due to a blockage caused by gallstones. The condition is not only painful but can lead to significant complications if not treated promptly. In this article, we delve into the symptoms, causes, diagnostic procedures, and effective treatments for acute cholecystitis, providing essential information for those seeking to understand this urgent health issue. Symptoms of Acute Cholecystitis The onset of acute cholecystitis is typically marked by a sudden pain in the upper right side of the abdomen, which may also radiate to the back or right shoulder. This pain can be intense and may be accompanied by: Fever and chills Tenderness in the abdomen when touched Nausea and vomiting Abdominal bloating Patients might also experience symptoms such as jaundice (yellowing of the skin and eyes), particularly if the bile ducts are blocked.

Acute Intermittent Porphyria

Acute Intermittent Porphyria (AIP) is a rare metabolic disorder that is part of a group of conditions known as porphyrias. These conditions are characterized by problems in the production of heme, an essential component of hemoglobin in the blood that helps transport oxygen. AIP specifically involves a deficiency in one of the enzymes needed for the synthesis of heme, leading to the accumulation of toxic substances in the body that can cause a variety of symptoms. Understanding Acute Intermittent Porphyria is crucial for managing the condition effectively and improving the quality of life for those affected. The hallmark of AIP is the acute, painful attacks that can occur, which are often triggered by factors such as certain medications, stress, alcohol consumption, hormonal changes, or fasting. These attacks can manifest as severe abdominal pain, nausea, vomiting, and neurological complications like weakness, tingling, or even paralysis.

Acute kidney injury (AKI)

What Is Acute Kidney Injury (AKI)? Acute Kidney Injury (AKI), also known as acute renal failure, is a sudden loss of kidney function that develops over hours or days. It causes a rapid build-up of waste products like creatinine and urea in the blood and disrupts the body’s ability to maintain fluid, electrolyte, and acid-base balance. AKI is common in hospitalized patients, especially those in intensive care units, and requires prompt detection and treatment. What Causes Acute Kidney Injury? AKI can be triggered by a wide range of factors, often classified into three categories: 1. Prerenal (Before the Kidneys) Low blood pressure (hypotension) Severe dehydration Heart failure Blood loss or shock 2. Intrinsic (Within the Kidneys) Acute tubular necrosis (ATN) Glomerulonephritis Nephrotoxic medications (e.g., NSAIDs, some antibiotics) Sepsis 3.

Acute lymphoblastic leukaemia (ALL)

Acute Myocardial Infarction (Heart Attack)

Acute myocardial infarction (AMI), commonly known as a heart attack, occurs when blood flow to a portion of the heart muscle is suddenly blocked, causing tissue damage or death due to lack of oxygen. This blockage is most often caused by a blood clot forming in a coronary artery that has been narrowed by atherosclerotic plaque buildup (cholesterol deposits and calcium), though it can also result from coronary artery spasm, dissection, or embolism. Symptoms of a heart attack typically include sudden chest pain or pressure (often described as squeezing, tightness, or heaviness), pain radiating to the left arm, jaw, neck, or back, shortness of breath, cold sweats, nausea, lightheadedness, and overwhelming fatigue. However, some people, particularly women, older adults, and diabetics, may experience atypical symptoms such as unusual fatigue, indigestion-like discomfort, or no chest pain at all.

Acute pancreatitis

Understanding Pancreatitis Acute: Causes, Symptoms, and Treatments Acute pancreatitis is sudden inflammation of the pancreas, marked by sharp abdominal pain that may require urgent medical attention. Understanding its triggers, such as gallstones and alcohol use, can be crucial. This article provides insights on detection, treatment options, and prevention strategies for pancreatitis acute, guiding you through this sudden health challenge. Key Takeaways Acute pancreatitis is a sudden inflammation of the pancreas with potential life-threatening complications, while chronic pancreatitis is a long-term condition leading to permanent damage. The primary causes of acute pancreatitis include gallstones and long-term heavy alcohol use, but it can also be triggered by medications, genetic factors, and high levels of triglycerides or calcium. Treatment of acute pancreatitis involves hospitalization for pain management, nutritional support, and monitoring for complications, with long-term management focusing on lifestyle changes to prevent recurrence.

Addison’s Disease

Addison's disease, also known as primary adrenal insufficiency, is a rare but serious endocrine disorder where the adrenal glands do not produce sufficient steroid hormones, particularly cortisol and aldosterone. It can occur at any age and affects both sexes equally. The condition is usually caused by an autoimmune response where the body's immune system mistakenly attacks and damages the adrenal glands, leading to their inability to produce hormones efficiently. Symptoms of Addison's disease develop gradually and can include chronic fatigue, muscle weakness, weight loss, low blood pressure, and hyperpigmentation of the skin. One of the hallmark features of Addison's disease is an increased pigmentation of the skin, particularly in areas exposed to friction or pressure, and in the creases of the palms. Patients may also experience salt cravings due to the lack of aldosterone, which helps regulate sodium and potassium in the body.

Adrenal fatigue

Understanding Adrenal Fatigue: Symptoms, Causes, and Management Adrenal fatigue is a controversial concept that describes a collection of symptoms believed to result from chronic stress and overworked adrenal glands. While not officially recognized by mainstream medicine, many individuals report experiencing persistent fatigue and other related symptoms. What is Adrenal Fatigue? Adrenal fatigue is theorized to occur when the adrenal glands, responsible for producing hormones like cortisol, become overwhelmed by prolonged stress. This purportedly leads to suboptimal hormone production, resulting in fatigue and other symptoms. However, it's important to note that this concept lacks scientific consensus.

Adrenal Hyperplasia

Understanding Adrenal Hyperplasia: Symptoms, Diagnosis, and Biomarkers Adrenal hyperplasia, often referred to as Congenital Adrenal Hyperplasia (CAH), is a group of genetic disorders affecting the adrenal glands. These glands, located atop the kidneys, play a crucial role in producing hormones like cortisol, aldosterone, and androgens. CAH is caused by enzyme deficiencies, primarily 21-hydroxylase, leading to improper hormone production. This condition can manifest in various forms, ranging from mild to severe, each with distinct symptoms and health implications. Individuals with adrenal hyperplasia may experience symptoms such as abnormal growth patterns, early onset of puberty, and in severe cases, life-threatening adrenal crises. Women might face virilization, exhibiting male-like characteristics due to excessive androgen production. Early diagnosis and treatment are vital to managing symptoms and preventing complications. Treatment typically involves hormone replacement therapy to balance the hormones that the adrenal glands cannot produce adequately.

Adrenal Insufficiency

Adrenal Insufficiency (Addison’s Disease) – Overview and Guide Introduction to Adrenal Insufficiency Adrenal insufficiency is a condition where the adrenal glands do not produce enough essential hormones, primarily cortisol (and in some cases aldosterone). There are two main forms: primary adrenal insufficiency, known as Addison’s disease, and secondary adrenal insufficiency. In Addison’s disease, the adrenal glands themselves are damaged or diseased and cannot meet the body’s hormone needs. This often happens due to an autoimmune attack on the adrenal cortex (the gland’s outer layer) that destroys hormone-producing cells. In contrast, secondary adrenal insufficiency occurs when the pituitary gland (a gland at the base of the brain) fails to signal them properly with a hormone called ACTH. Without enough ACTH, the adrenals don’t get the “message” to make cortisol. Secondary adrenal insufficiency can develop, for example, after long-term use of corticosteroid medications that suppress the pituitary, or from pituitary tumors or surgery.

Adrenal Tumors

Adrenal tumors are abnormal growths that develop in the adrenal glands, which are small, triangular-shaped glands located on top of each kidney. These glands play a crucial role in producing hormones such as adrenaline, cortisol, and aldosterone, which help regulate metabolism, immune response, blood pressure, and stress responses. Adrenal tumors can be benign (non-cancerous) or malignant (cancerous), with common types including adenomas, pheochromocytomas, and adrenocortical carcinomas. Symptoms of adrenal tumors vary depending on the type and size of the tumor and may include high blood pressure, unexplained weight gain or loss, fatigue, muscle weakness, and hormonal imbalances that could lead to conditions like Cushing's syndrome or Conn's syndrome. Diagnosis typically involves imaging tests like CT scans or MRIs, blood tests to check hormone levels, and sometimes a biopsy to determine the nature of the tumor. Treatment options for adrenal tumors depend on the type, size, and whether the tumor is producing excess hormones.

Aflatoxicosis

AL Amyloidosis

Albuminuria

Understanding Albuminuria: Causes, Symptoms, and Treatments What is Albuminuria? Albuminuria is a medical condition characterized by the presence of albumin, a type of protein, in the urine. Normally, healthy kidneys filter waste from the blood and retain essential proteins, like albumin. However, when the kidneys are damaged or diseased, they can allow albumin to pass into the urine, leading to albuminuria. Detecting albuminuria early is crucial because it can be an indicator of kidney damage and other health issues. Why is Albumin Important? Albumin is a protein made by the liver that plays a critical role in maintaining the body's fluid balance. It helps keep fluid in the bloodstream, so it doesn't leak into other tissues. Albumin also carries various substances throughout the body, including hormones, vitamins, and enzymes. Low levels of albumin in the blood can lead to swelling (edema), as fluid leaks into body tissues, and can be a sign of kidney problems. Prevalence of Albuminuria Albuminuria is relatively common, affecting approximately 8-10% of the general population.

Alcoholic ketoacidosis

Alcoholic ketoacidosis (AKA) is a serious metabolic emergency that develops when heavy alcohol use, poor nutrition, and repeated vomiting cause the body to produce excess ketones. It typically presents with nausea, abdominal pain, and vomiting—often in individuals whose blood tests show a high anion gap and metabolic acidosis. Unlike diabetic ketoacidosis, blood glucose levels are usually normal or only slightly elevated. This condition occurs when depleted glucose stores force the body to break down fat for energy, producing ketones such as beta-hydroxybutyrate and acetoacetate. As these ketones accumulate, they lead to metabolic acidosis. Alcohol further disrupts normal energy metabolism, promoting ketone buildup and impairing glucose use. What Causes Alcoholic Ketoacidosis? Alcoholic ketoacidosis typically develops after a period of heavy alcohol intake followed by reduced food consumption.

Alcoholic Liver Disease

Allergic Asthma

Allergic Disorders

Allergic disorders are conditions in which the immune system overreacts to substances that are typically harmless, known as allergens. These allergens can include pollen, dust mites, pet dander, certain foods, insect venom, and medications. In individuals with allergies, the immune system identifies these substances as threats and produces an exaggerated response—most commonly mediated by immunoglobulin E (IgE)—leading to inflammation and a wide range of symptoms. Allergic disorders can affect multiple organ systems and present in various forms, including allergic rhinitis (hay fever), asthma, atopic dermatitis (eczema), food allergies, and drug hypersensitivities. Symptoms vary depending on the type and severity of the reaction but may include sneezing, nasal congestion, itchy or watery eyes, skin rashes, hives, gastrointestinal discomfort, and respiratory symptoms such as wheezing or shortness of breath. In severe cases, allergic reactions can progress to anaphylaxis, a life-threatening condition requiring immediate medical attention.

Allergic Reaction

Allergic Rhinitis

Allergic Rhinitis (Hay Fever) Allergic rhinitis is a common allergic condition in which the immune system reacts to airborne allergens such as pollen, dust mites, or pet dander. This triggers inflammation in the nasal passages and leads to symptoms like sneezing, congestion, and itching. It is closely associated with asthma, eczema, and other atopic conditions. On blood tests, allergic rhinitis is most often reflected by elevated eosinophils, one of the key white blood cell types involved in allergic responses. This can also contribute to an increased MXD% on a CBC, since eosinophils are part of the mixed cell group. Why This Matters for Your Blood Test Results Allergic rhinitis commonly raises eosinophil levels Elevated eosinophils are the most frequent cause of a high MXD% Total IgE is often elevated in allergic individuals Changes are usually mild and not dangerous Levels may fluctuate with allergen exposure (e.g., pollen season) If your results show mildly elevated eosinophils or MXD and you have allergy symptoms, allergic rhinitis is one of the most likely explanations.

Allergic Sinusitis

Alzheimer's Disease

What Is Alzheimer’s Disease? Understanding Symptoms, Causes, Diagnosis, and Treatment Alzheimer’s Disease (AD) is the most common cause of dementia in older adults, accounting for 60–80% of all dementia cases. It is a progressive neurodegenerative disorder that leads to a gradual decline in memory, thinking, behavior, and the ability to perform everyday activities. Key Characteristics and Symptoms Alzheimer’s typically begins with mild memory loss, especially short-term memory, and progressively impairs: Cognitive abilities (e.g., decision-making, reasoning) Executive functions (e.g., planning, problem-solving) Language and communication Visuospatial skills (e.g., recognizing objects or navigating spaces) As the disease advances, patients often experience personality and behavioral changes, including depression, apathy, social withdrawal, agitation, and confusion. In its severe stages, Alzheimer's leads to complete dependency and loss of independent function. Causes and Risk Factors The exact cause of Alzheimer’s disease remains unclear.

Aminoacidopathy

Aminoacidopathy: Understanding a Complex Metabolic Disorder Aminoacidopathy refers to a group of inherited metabolic disorders that disrupt the body's ability to process specific amino acids—the building blocks of proteins. While these conditions can significantly impact health and quality of life, early diagnosis and effective management can enable many individuals to thrive. What is Aminoacidopathy? Aminoacidopathies occur due to genetic defects in the enzymes responsible for breaking down particular amino acids. This leads to the accumulation of amino acids or their byproducts in the body, which can be toxic and cause various health problems [1, 2]. Types of Aminoacidopathies Aminoacidopathies vary based on the affected amino acids and their symptoms. Common examples include: Phenylketonuria (PKU): Impairs the metabolism of phenylalanine [3]. Maple Syrup Urine Disease (MSUD): Affects the breakdown of branched-chain amino acids [4]. Homocystinuria: Disrupts methionine metabolism [5]. Tyrosinemia: Involves issues with tyrosine breakdown [6].

Amyloid Pathology

Androgenic Alopecia / Female Pattern Hair Loss

Anemia

Anemia of Chronic Disease

Anisocytosis

Anisocytosis means your red blood cells vary in size more than usual. It is an observation on a blood test, not a diagnosis in itself. What Is Anisocytosis? Understanding Causes, Symptoms, and Diagnosis Anisocytosis is a medical term used to describe red blood cells (RBCs) that vary significantly in size. Normally, healthy red blood cells are fairly uniform in shape and size, allowing them to transport oxygen efficiently throughout the body. When anisocytosis occurs, the variation in cell size may indicate an underlying health condition, particularly forms of anemia or nutritional deficiencies. Types of Anisocytosis Anisocytosis is often categorized based on the size of the abnormal red blood cells: Microcytosis – presence of unusually small red blood cells Macrocytosis – presence of unusually large red blood cells Mixed Anisocytosis – a combination of both small and large RBCs This condition is commonly detected during a complete blood count (CBC) test, where the red cell distribution width (RDW) is elevated, signaling size variability among the red blood cells.

Ankylosing spondylitis

Understanding Ankylosing Spondylitis: Symptoms, Diagnosis, and Treatment Ankylosing spondylitis (AS) is a chronic inflammatory condition primarily affecting the spine and sacroiliac joints, where the spine meets the pelvis. This disease is a type of arthritis that causes inflammation of the vertebrae, leading to severe, chronic pain and discomfort. Over time, ankylosing spondylitis can cause the vertebrae to fuse, resulting in a loss of spine flexibility and a hunched-forward posture. It most commonly begins in early adulthood, and men are more frequently affected than women. Understanding the symptoms, diagnosis, and treatment options for ankylosing spondylitis is crucial for managing this debilitating condition effectively. Symptoms of Ankylosing Spondylitis The symptoms of ankylosing spondylitis can vary from mild to severe and often develop gradually. The most common initial symptom is pain and stiffness in the lower back and hips, especially in the morning or after periods of inactivity. This discomfort can extend to the neck and other areas of the spine.

Anorexia Nervosa

Anorexia nervosa is a serious and potentially life-threatening eating disorder characterized by an intense fear of gaining weight, a distorted body image, and extreme measures to maintain a low body weight. This complex mental health condition typically develops during adolescence or early adulthood, affecting people of all genders, though it is more commonly diagnosed in females. Individuals with anorexia nervosa often restrict their food intake severely, engage in excessive exercise, and may use purging behaviors such as self-induced vomiting or laxative abuse. The physical consequences of anorexia can be severe, impacting nearly every system in the body. These may include malnutrition, osteoporosis, cardiovascular problems, gastrointestinal issues, and hormonal imbalances. Psychologically, anorexia is often accompanied by depression, anxiety, and obsessive-compulsive tendencies. Early intervention and comprehensive treatment, involving a team of medical professionals, mental health experts, and nutritionists, are crucial for recovery.

Anovulation

Antiphospholipid syndrome (APS)

Antiphospholipid Syndrome (APS) is a disorder where the immune system, which usually fights off harmful invaders like viruses and bacteria, mistakenly attacks certain proteins in the blood, leading to an increased risk of forming blood clots. These clots can develop in both veins and arteries anywhere in the body and can lead to serious health problems. For example, clots in the legs (deep vein thrombosis) can cause pain and swelling, while clots that travel to the lungs (pulmonary embolism) can be life-threatening. APS can also cause complications in pregnancy, such as miscarriages, preterm delivery, or severe preeclampsia (a condition marked by high blood pressure and potential damage to organs like the liver and kidneys). The syndrome is called "antiphospholipid" because the immune system creates antibodies against phospholipids, a type of fat found in the lining of cells, including blood cells and the heart's inner walls. Why the immune system does this isn't entirely clear, but these antibodies can make the blood more likely to clot.

Aplastic Anemia

What Is Aplastic Anemia? Aplastic anemia is a rare but serious condition in which the bone marrow fails to produce enough new blood cells. This leads to low levels of red blood cells, white blood cells, and platelets—a state known as pancytopenia. Because these cells are responsible for carrying oxygen, fighting infections, and helping blood clot, aplastic anemia can affect many systems in the body. What Happens in the Body In healthy individuals, the bone marrow continuously makes new blood cells from hematopoietic stem cells. In aplastic anemia, this process is disrupted—most often because the immune system mistakenly attacks these stem cells. As a result, the bone marrow becomes hypocellular (less full and less active). Over time, blood counts fall, and the risk of fatigue, infections, and bleeding increases.

Appendicitis

Aromatic L-amino acid decarboxylase deficiency (AADCD)

Understanding Aromatic L-amino Acid Decarboxylase Deficiency (AADCD): Symptoms, Diagnosis, and Treatment Aromatic L-amino acid decarboxylase deficiency (AADCD) is a rare genetic disorder that significantly impacts the nervous system. This condition, also known as AADC deficiency, results from mutations in the DDC gene, which encodes the enzyme aromatic L-amino acid decarboxylase. This enzyme is crucial for synthesizing neurotransmitters such as dopamine and serotonin. Without proper levels of these neurotransmitters, individuals with AADCD experience a range of severe neurological symptoms that can affect their overall development and quality of life. Raising awareness about AADCD is essential for early diagnosis and management, ultimately improving the prognosis for affected individuals. Symptoms of AADCD The symptoms of AADCD typically appear in infancy or early childhood and can vary in severity. Common signs include hypotonia (reduced muscle tone), developmental delays, and autonomic dysfunction, which affects bodily functions such as heart rate and digestion.

Arteriovenous Malformation (AVM)

Asthma

What is Asthma? Asthma is a chronic inflammatory disease that affects the airways, specifically the bronchi—tubes that carry air in and out of the lungs. In asthma, these airways become inflamed and overly sensitive (hyperreactive) to various triggers, leading to episodes of airway narrowing and obstruction. How Does Asthma Affect the Airways? When a person with asthma is exposed to triggering factors—such as allergens, pollutants, cold air, exercise, or stress—the inflamed airways respond with: Bronchoconstriction (tightening of airway muscles) Mucus overproduction (clogging the air passages) Increased inflammation (further swelling of airway tissues) These reactions restrict airflow, making it difficult to breathe and leading to common asthma symptoms such as wheezing, coughing, shortness of breath (dyspnea), and chest tightness. The Chronic Inflammation Behind Asthma Asthma is more than a temporary airway problem; it is a chronic inflammatory condition of the lung mucosa.

Asymptomatic Bacteriuria

Ataxia

Ataxia is a term used to describe a group of neurological disorders that affect coordination, balance, and speech, making it challenging for those affected to perform everyday activities that require precise movements. Imagine your brain as the command center sending out signals to various parts of your body to move in a synchronized and smooth manner. In ataxia, this communication system faces interference, leading to uncoordinated or clumsy movements that are not intentional. This can manifest in various ways, such as stumbling while walking, difficulty with fine motor tasks like writing or buttoning a shirt, and changes in speech clarity. The causes of ataxia can vary widely; it may be a result of genetic factors, where mutations in certain genes lead to inherited forms of the disorder, or it can stem from external factors such as a stroke, tumor, or even exposure to toxins. Additionally, some types of ataxia may develop as a result of autoimmune diseases, where the body's immune system mistakenly attacks its own brain cells.

Atherogenic Dyslipidemia

Atherosclerosis: Symptoms, Causes, Diagnosis, and Prevention

Last updated: February 10, 2026 Atherosclerosis is a chronic cardiovascular condition in which plaque builds up inside the arteries, causing them to narrow and harden. Over time, this reduces blood flow to vital organs and increases the risk of heart attack, stroke, and peripheral artery disease. Early detection and management are critical because atherosclerosis often develops silently for years before symptoms appear. What is Atherosclerosis? Atherosclerosis is a progressive disease of the arteries characterized by the accumulation of plaque made up of cholesterol, fat, calcium, inflammatory cells, and other substances. This plaque can: Narrow arteries (arterial stenosis) Reduce oxygen delivery to tissues Trigger blood clots Lead to cardiovascular events such as heart attack or stroke Atherosclerosis is the underlying cause of most cardiovascular disease (CVD) worldwide and is strongly linked to lipid imbalances, inflammation, and metabolic health.

Atopic Dermatitis

Atrial Fibrillation

Autoimmune Conditions

Autoimmune Disease

Autoimmune encephalitis

Autoimmune encephalitis is a complex and serious condition in which the body's immune system mistakenly attacks its own brain cells, leading to inflammation of the brain (encephalitis). This can cause a wide range of neurological and psychiatric symptoms that vary greatly from person to person but often include memory loss, seizures, mood swings, and sometimes even psychotic behavior. The disease can be triggered by various factors, including infections, tumors, or for reasons that remain unknown in many cases. Autoimmune encephalitis is a relatively rare disorder, but it has gained recognition over the past few years because it can often be treated effectively once diagnosed. The immune system's attack on the brain involves antibodies or immune cells targeting specific proteins in the brain, which can disrupt normal brain function.

Autoimmune hepatitis (AIH)

Condition Overview & Clinical Context Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease in which the immune system mistakenly attacks liver cells, leading to ongoing liver inflammation and progressive tissue damage. Over time, untreated AIH can result in fibrosis, cirrhosis, liver failure, and an increased risk of hepatocellular carcinoma. When identified early, however, AIH is often highly treatable, and many individuals achieve long-term disease control. AIH can affect individuals of any age or sex but is more commonly diagnosed in women. The condition may develop gradually with subtle symptoms or present abruptly with acute hepatitis. In some cases, AIH is discovered incidentally through abnormal liver enzyme results on routine blood testing. Immune Mechanism & Disease Development In autoimmune hepatitis, immune tolerance to liver antigens is lost. Activated immune cells and autoantibodies target hepatocytes, triggering inflammation and cellular injury.

Autoimmune Neutropenia

Autonomic Failure

B cell lymphoma

B-cell lymphoproliferative disorders

Bacterial Infection

Bacterial infections occur when harmful bacteria invade the body and multiply, triggering an immune response that can affect various organs and tissues. Common bacterial infections include pneumonia, urinary tract infections, skin and soft tissue infections like cellulitis, strep throat, and bacterial gastroenteritis. Symptoms typically include fever, localized pain or swelling, redness at the infection site, and general malaise, though presentation varies depending on which part of the body is affected. The immune system responds to bacterial infections by rapidly producing white blood cells to fight the invading pathogens, which can be detected through blood tests showing elevated infection markers. Diagnosis usually involves clinical evaluation, physical examination, and laboratory tests including blood work and cultures to identify the specific bacteria causing the infection. Treatment primarily consists of antibiotics targeted to the identified or suspected bacterial strain, along with supportive care such as rest, hydration, and pain management.

Bacterial Infections

Bacterial infections are caused by pathogenic bacteria—microscopic organisms capable of invading tissues, producing toxins, and triggering immune responses. Common examples include urinary tract infections (UTIs), strep throat, pneumonia, and foodborne illnesses such as salmonella. The body’s immune system plays a critical role in identifying and eliminating bacterial threats. However, factors such as weakened immunity, chronic disease, poor hygiene, or exposure to contaminated food, water, or surfaces can increase susceptibility. Symptoms depend on the site of infection but often include fever, chills, swelling, redness, pain, and fatigue. In systemic infections, symptoms may escalate to include rapid heart rate, confusion, or low blood pressure, indicating a more serious condition such as sepsis. Diagnosis typically involves clinical evaluation and laboratory testing, including blood tests, cultures, or biomarker analysis. Elevated markers such as white blood cell count (WBC), C-reactive protein (CRP), or procalcitonin may indicate an active bacterial infection.

Bacterial Meningitis

Bacterial Overgrowth

Basopenia

Basophilia

Basophilia: Understanding the Condition What is Basophilia? Basophilia, also known as basophilic disorder, occurs when your body produces an excessive number of basophils. Basophils are a type of white blood cell that plays a crucial role in your immune system by protecting your body from infections and responding to allergens. A high basophil count may indicate an infection, or it could be a sign of more serious conditions like leukemia or autoimmune diseases. Normally, basophil levels range from 0 to 300 basophils per microliter of blood, or less than 2% of total white blood cells. Basophilia is relatively rare, occurring in less than 1% of the general population. Causes of Basophilia Basophilia happens when there is an unusually high number of basophils in your blood. This can be caused by various factors, including: - Myeloproliferative Disorders: These are conditions where the bone marrow produces too many blood cells. Examples include chronic myelogenous leukemia (CML), primary myelofibrosis, and essential thrombocythemia.

Benign prostatic hyperplasia (BPH)

Benign Prostatic Hyperplasia (BPH): Symptoms, Diagnosis, and Treatment Guide for Prostate Enlargement Benign Prostatic Hyperplasia (BPH), also known as prostate gland enlargement, is one of the most common conditions affecting men as they age. This in-depth guide covers BPH symptoms, diagnosis methods, and treatment options to help you understand and manage this condition effectively. Whether you're searching for early signs of BPH or looking for the best treatments for enlarged prostate, this article provides everything you need to know. What is Benign Prostatic Hyperplasia (BPH)? Benign Prostatic Hyperplasia (BPH) refers to the non-cancerous enlargement of the prostate gland. The prostate is a small gland located below the bladder, surrounding the urethra—the tube that carries urine out of the body. As men age, the prostate often grows larger, leading to urinary problems due to its position near the bladder and urethra. How Common is BPH? BPH affects approximately 50% of men over 50. By age 80, up to 90% of men experience some degree of prostate enlargement.

Beta Thalassemia

Beta Thalassemia is a genetic blood disorder that affects the body's ability to produce hemoglobin, the protein in red blood cells responsible for carrying oxygen throughout the body. This condition is caused by mutations in the HBB gene on chromosome 11, which leads to reduced or absent production of beta-globin, one of the two subunits of hemoglobin. Beta Thalassemia is inherited in an autosomal recessive pattern, meaning a person must inherit two mutated genes (one from each parent) to be affected by the condition. There are several forms of Beta Thalassemia, ranging from mild to severe, based on the mutations' effects on hemoglobin production. The mildest form is known as Beta Thalassemia minor or Beta Thalassemia trait, where individuals often experience little to no symptoms and may not even be aware they carry the gene mutation. More severe forms include Beta Thalassemia intermedia and Beta Thalassemia major, also known as Cooley's anemia.

Biliary Obstruction

Bipolar disorder

Understanding Bipolar Disorder: Symptoms, Diagnosis, and Treatment Bipolar disorder is a mental health condition characterized by extreme mood swings that include emotional highs (mania or hypomania) and lows (depression). These mood shifts can affect sleep, energy, activity, judgment, behavior, and the ability to think clearly. Bipolar disorder is a lifelong condition, but with proper management, individuals can lead fulfilling lives. Understanding the symptoms, diagnostic methods, and treatment options is crucial for effective management of this disorder. Symptoms of Bipolar Disorder The symptoms of bipolar disorder are divided into two main types: manic/hypomanic episodes and depressive episodes. During a manic episode, individuals may feel euphoric, full of energy, or unusually irritable. They may engage in risky behaviors, have racing thoughts, speak rapidly, and require less sleep. Hypomania is a less severe form of mania that does not cause significant impairment in social or occupational functioning.

Bladder Cancer

Bone Marrow Disorders

Bone marrow disorders are a group of conditions that affect the production and development of blood cells within the bone marrow—the soft, spongy tissue found inside bones responsible for generating red blood cells, white blood cells, and platelets. When bone marrow function is disrupted, it can lead to abnormalities in one or more of these cell lines, resulting in a wide range of clinical consequences, from mild cytopenias to life-threatening hematologic disease. These disorders include conditions such as anemia (including aplastic anemia), myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPNs), leukemia, and bone marrow infiltration from cancers or fibrosis (myelofibrosis). Depending on the underlying cause, bone marrow disorders may involve underproduction, overproduction, or dysfunctional development of blood cells. At the biological level, bone marrow disorders often arise from abnormalities in hematopoietic stem cells—the precursor cells that give rise to all blood cell types.

Bone Marrow Stress / Recovery

Bone marrow stress or recovery refers to the bone marrow's response to conditions that either suppress blood cell production or require increased production to meet the body's demands, often resulting in temporary changes in blood cell counts and the release of immature cells into circulation. Bone marrow stress can be caused by chemotherapy or radiation therapy (which damage rapidly dividing cells including bone marrow), severe infections that deplete the body's reserves of infection-fighting cells, significant blood loss requiring rapid red blood cell replacement, nutritional deficiencies (such as vitamin B12, folate, or iron deficiency), certain medications that suppress bone marrow function, and autoimmune conditions where the immune system attacks blood-forming cells. During the recovery phase, the bone marrow rebuilds its reserves and may temporarily release immature blood cells into circulation as production accelerates, which is often enhanced by medications called growth factors (such as G-CSF, erythropoietin, or thrombopoietin) that stimulate specific blood cell lines.

Bone Marrow Suppression

What Is Bone Marrow Suppression? Bone marrow suppression is a condition in which the bone marrow produces fewer blood cells than normal. This can affect red blood cells, white blood cells, and platelets, leading to a range of symptoms depending on which cell lines are most impacted. In more severe cases, this can result in Pancytopenia, where all three major blood cell types are reduced. Because these cells are essential for carrying oxygen, fighting infections, and helping blood clot, bone marrow suppression can affect many systems in the body. What Happens in the Body The bone marrow is responsible for continuously producing new blood cells from hematopoietic stem cells. In bone marrow suppression, this process slows down or becomes less effective. As a result: Fewer red blood cells are produced, reducing oxygen delivery to tissues Fewer white blood cells are produced, weakening the immune response Fewer platelets are produced, increasing bleeding risk The degree of suppression can vary from mild and temporary to severe and life-threatening.

Bone Metastases

Breast Cancer

Breast cancer is a malignant condition characterized by the uncontrolled growth of cells within breast tissue — most commonly originating in the ducts (ductal carcinoma) or lobules (lobular carcinoma). It is the most common cancer in women worldwide and a leading cause of cancer-related mortality, though outcomes have improved significantly with early detection and advances in treatment. Breast cancer is not a single disease but a biologically diverse group of tumors with distinct molecular subtypes, risk profiles, and treatment responses. These differences are largely defined by the presence or absence of hormone receptors (estrogen and progesterone) and HER2 expression, which guide both prognosis and therapy. Early identification through screening and prompt diagnostic evaluation is critical, as breast cancer is highly treatable — and often curable — when detected at an early stage. How Breast Cancer Develops Normal breast cells grow and divide in a regulated manner.

Cachexia

Understanding Cachexia: A Complex Metabolic Syndrome Cachexia, also known as wasting syndrome, is a multifaceted metabolic disorder often associated with chronic, life-threatening illnesses like cancer, heart disease, chronic kidney disease, and chronic obstructive pulmonary disease (COPD). It is characterized by severe weight loss and muscle wasting, even in individuals who consume adequate nutrition. Unlike regular weight loss, cachexia is largely irreversible through conventional nutritional support or increased caloric intake, making it a challenging condition for both patients and healthcare providers to manage. The term "cachexia" is derived from the Greek words "kakos" meaning "bad" and "hexis" meaning "condition," reflecting the profound physical deterioration that patients experience. In addition to weight loss, cachexia is often accompanied by fatigue, anemia, weakness, and a loss of appetite (anorexia), further complicating the patient's ability to maintain their nutritional needs.

Cancer

Candidiasis

Candidiasis, a fungal infection caused by Candida species, predominantly Candida albicans, is a multifaceted condition that can manifest in various forms depending on the affected body site. Candida species are commensal organisms commonly found in the human microbiota, residing in the oral cavity, gastrointestinal tract, and vaginal mucosa. Under normal circumstances, these yeasts coexist harmlessly within these ecosystems, but certain conditions can provoke an overgrowth, leading to candidiasis. The most common forms of this infection include oral thrush, characterized by white, creamy lesions in the mouth or on the tongue, vaginal yeast infections with symptoms like itching, redness, and discharge, and invasive candidiasis, where the yeast enters the bloodstream, potentially affecting various organs. Invasive candidiasis is particularly concerning in immunocompromised individuals, such as those with HIV/AIDS, undergoing chemotherapy, or taking immunosuppressive drugs, as it can lead to systemic and potentially life-threatening conditions.

Cardiomyopathy

Cardiovascular disease (CVD)

21 May 2025 Cardiovascular Disease (CVD): A Comprehensive Guide What is Cardiovascular Disease (CVD)? Cardiovascular disease (CVD) refers to a class of diseases that affect the heart and blood vessels. These conditions include coronary artery disease (CAD), heart failure, arrhythmias, and cerebrovascular diseases like stroke. CVD is one of the leading causes of death worldwide, accounting for nearly 18 million deaths each year according to the World Health Organization (WHO). The disease often develops due to the accumulation of plaque in the arteries, a condition known as atherosclerosis, which restricts blood flow to vital organs and tissues. Types of Cardiovascular Disease: CVD encompasses a variety of conditions, including: Coronary Artery Disease (CAD): Caused by the narrowing or blockage of coronary arteries, it can lead to chest pain (angina) or heart attacks. Heart Failure: A condition where the heart is unable to pump enough blood to meet the body’s needs. Arrhythmia: Irregular heartbeats, which can be too fast (tachycardia), too slow (bradycardia), or erratic.

Catheter-Associated UTI (CAUTI)

Celiac Disease

What is Celiac Disease? Celiac disease is a chronic autoimmune disorder triggered by gluten, a protein found in wheat, barley, and rye. In people with genetic predisposition, consuming gluten activates the immune system, damaging the villi of the small intestine. This leads to malabsorption of nutrients and a wide range of symptoms. Celiac disease can appear at any age and may be silent, mild, or severe. If untreated, it can lead to long-term complications such as intestinal cancer, infertility, osteoporosis, and other autoimmune conditions. Symptoms of Celiac Disease Symptoms vary greatly between individuals and may be digestive, non-digestive, or even absent.

Central Hypothyroidism

Central Hypothyroidism: Causes, Diagnosis, and Why TSH Alone Can Miss It Central hypothyroidism is an underactive thyroid caused by a problem in the pituitary gland or hypothalamus rather than in the thyroid itself. The thyroid is capable of working normally — it is simply not receiving the signal to do so. That single difference changes how the condition is found, how it is confirmed, and which blood test is used to guide treatment. What is central hypothyroidism? In ordinary (primary) hypothyroidism, the thyroid gland underperforms and the pituitary responds by raising TSH. In central hypothyroidism the pituitary or hypothalamus is the source of the problem, so that TSH rise does not happen reliably. The pattern is: Low free T4 TSH that is low, normal, or only mildly raised Usually in the context of known or suspected pituitary or hypothalamic disease The Endocrine Society states that a free T4 below the laboratory reference range, together with a low, normal, or mildly elevated TSH in the setting of pituitary disease, usually confirms the diagnosis.

Cerebral Hemorrhage

Chickenpox (Varicella)

Chlamydia / Gonorrhea (Urethritis)

Chlamydia / Gonorrhea (Urethritis) Urethritis is inflammation of the urethra — the tube that carries urine out of the body. It is most commonly caused by sexually transmitted infections (STIs), with Chlamydia trachomatis and Neisseria gonorrhoeae (the bacterium responsible for gonorrhea) being the two most important and well-recognized causes. Both infections are common, frequently asymptomatic, and highly treatable — but if left undetected and untreated, they can cause serious complications including pelvic inflammatory disease, infertility, and chronic pelvic pain. Because symptoms can be mild or absent, regular screening is essential, especially if you are under 25 or have new partners. Urethritis caused by gonorrhea is called gonococcal urethritis. Urethritis caused by chlamydia or other non-gonococcal organisms is called non-gonococcal urethritis (NGU). Both can cause identical symptoms, and the two infections frequently co-exist — around 20–40% of people diagnosed with gonorrhea are also infected with chlamydia.

Choledocholithiasis

Cholelithiasis

Understanding Cholelithiasis: Symptoms, Diagnosis, and Treatment Cholelithiasis, commonly known as gallstones, is a prevalent health condition characterized by the formation of stones in the gallbladder. The gallbladder is a small organ located beneath the liver, responsible for storing bile, a digestive fluid produced by the liver. Gallstones can vary in size, from tiny grains to large stones, and they can cause significant discomfort and complications if not properly managed. Understanding the symptoms, diagnostic methods, and treatment options for cholelithiasis is essential for effective management and improved patient outcomes. Symptoms of Cholelithiasis The symptoms of cholelithiasis can range from mild to severe and may vary depending on the size and location of the gallstones. Common symptoms include abdominal pain, particularly in the upper right quadrant, which may radiate to the back or shoulder. This pain, known as biliary colic, often occurs after consuming fatty meals and can last from a few minutes to several hours.

Cholestasis

Cholestatic Liver Disease

Cholesterolosis

Understanding Cholesterolosis: Symptoms, Diagnosis, and Treatment Cholesterolosis, often referred to as "strawberry gallbladder," is a condition where cholesterol deposits build up on the gallbladder wall, giving it a speckled appearance similar to that of a strawberry. This condition is commonly associated with cholesterol metabolism disorders and can be a precursor to more serious gallbladder diseases, such as cholecystitis or gallstones. While cholesterolosis itself is usually benign, understanding its symptoms, diagnosis, and treatment is crucial for managing overall gallbladder health. Symptoms of Cholesterolosis Cholesterolosis often presents without any noticeable symptoms, especially in its early stages. However, as the condition progresses, some individuals may experience mild to moderate abdominal discomfort. This discomfort is typically felt in the upper right quadrant of the abdomen and can be accompanied by bloating, nausea, and indigestion. In some cases, these symptoms might be mistaken for other gastrointestinal issues.

Chronic Active EBV Infection

Chronic Fatigue Syndrome

Understanding Chronic Fatigue Syndrome: Symptoms, Diagnosis, and Treatment Chronic Fatigue Syndrome (CFS), also known as Myalgic Encephalomyelitis (ME), is a complex and debilitating health condition characterized by extreme fatigue that cannot be explained by any underlying medical condition. This fatigue is not alleviated by rest and often worsens with physical or mental activity. CFS affects millions of people worldwide, significantly impacting their quality of life. Understanding the symptoms, diagnosis, and treatment options for CFS is essential for managing this challenging condition effectively. Symptoms of Chronic Fatigue Syndrome The primary symptom of Chronic Fatigue Syndrome is persistent, overwhelming fatigue that lasts for six months or longer and is not improved by rest. This fatigue significantly interferes with daily activities and is often accompanied by a range of other symptoms. These can include muscle and joint pain, headaches, and sore throat.

Chronic Infections

At a Glance What it is: Infections that persist for weeks, months, or years despite treatment Common causes: Tuberculosis, Lyme disease, hepatitis B/C, HIV, chronic fungal infections Key symptoms: Persistent fatigue, recurring fever, weight loss, night sweats Lab markers: Elevated white blood cells (especially monocytes and lymphocytes), high CRP/ESR Treatment: Long-term antimicrobial therapy, immune support, and treatment of underlying conditions Note: This article is for educational purposes only and is not a substitute for medical advice. Always discuss persistent symptoms with your healthcare provider. What Are Chronic Infections? A chronic infection is an infection that persists in your body for weeks, months, or even years—despite your immune system’s attempts to eliminate it. Unlike acute infections (such as a common cold or strep throat), which resolve within days to weeks, chronic infections can evade or suppress immune defenses, allowing the pathogen to survive long-term.

Chronic inflammatory demyelinating polyneuritis (HCC)

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a slowly developing autoimmune disorder in which the body's immune system attacks the myelin that insulates and protects the body’s nerves. The exact cause isn't known. Common symptoms are gradual weakness or sensation changes in the arms or legs. This might get worse over time, or it might come and go. Early treatment is important to limit disease progression. It includes medicines or other treatments to suppress the immune system.

Chronic Inflammatory Diseases

Chronic inflammatory diseases are a group of conditions characterized by persistent, dysregulated inflammation that can affect multiple tissues and organ systems over time. Unlike acute inflammation—which is a short-term, protective response to injury or infection—chronic inflammation is prolonged and often occurs without a clear external trigger, contributing to tissue damage and disease progression. These conditions encompass a wide spectrum of disorders, including autoimmune diseases (such as rheumatoid arthritis and lupus), metabolic disorders (such as type 2 diabetes and obesity-related inflammation), cardiovascular disease, inflammatory bowel disease (IBD), and neuroinflammatory conditions. While the underlying causes vary, they share a common feature: an ongoing activation of the immune system that fails to resolve properly. At the biological level, chronic inflammation involves continuous signaling between immune cells, cytokines, and inflammatory pathways. Key mediators include interleukins (e.g., IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP).

Chronic kidney disease

What is Chronic Kidney Disease? Chronic Kidney Disease (CKD) is a common condition that many of us overlook. It’s a progressive disease that gets worse over time if not managed properly. CKD is slow loss of kidney function which filters waste and excess fluid from the blood and produces hormones that control blood pressure. When the kidneys are damaged, these waste products build up in the body and cause many health problems. CKD is divided into 5 stages from mild kidney damage in Stage 1 to complete kidney failure in Stage 5 which may require dialysis or kidney transplant to survive. End stage kidney disease and end stage renal disease is the critical stage where normal kidney function has stopped and requires major medical intervention. The progression of CKD can be slow, often takes years, that’s why early detection and management is key to slowing down the disease and living a good life. Early detection and monitoring is especially important to prevent kidney disease and its complications.

Chronic Liver Disease

Chronic liver disease refers to the progressive deterioration of liver function caused by ongoing injury to liver tissue. Over time, this damage leads to inflammation, fibrosis (scar tissue formation), and eventually cirrhosis—an advanced stage marked by severe structural disruption and impaired blood flow through the liver. The liver is a critical organ responsible for over 500 vital functions, including detoxifying harmful substances, producing clotting factors and immune proteins, metabolizing nutrients and medications, regulating blood sugar, storing vitamins and minerals, producing bile for digestion, and synthesizing cholesterol and lipids. As liver function declines, widespread systemic effects can occur. Chronic liver disease affects millions globally and is a leading cause of morbidity and mortality. Cirrhosis ranks among the top causes of death worldwide. Because symptoms often appear late, it is frequently referred to as a “silent disease.”

Chronic lymphocytic leukaemia (CLL)

Chronic lymphocytic leukemia (CLL)

Understanding Chronic Lymphocytic Leukemia (CLL): A Comprehensive Guide What is Chronic Lymphocytic Leukemia (CLL)? Chronic lymphocytic leukemia (CLL) is a type of cancer that affects the blood and bone marrow, specifically targeting a subset of white blood cells known as lymphocytes. These cells are part of the immune system and play a crucial role in fighting infections. In CLL, these lymphocytes become abnormal, multiply uncontrollably, and fail to function properly, crowding out healthy blood cells in the bone marrow. CLL is considered a slow-growing leukemia, meaning that it progresses more gradually compared to other types of leukemia. Key Facts About CLL Common in older adults: CLL primarily affects individuals over the age of 60, and it is rare in younger populations. Slow progression: Many people with CLL live for years without needing treatment because the disease progresses slowly. Chronic condition: While CLL is not typically curable, it can be managed effectively in many cases.

Chronic Myelogenous Leukaemia (CML)

Chronic Myelogenous Leukemia

What Is Chronic Myelogenous Leukemia? Chronic myelogenous leukemia (CML) is a type of blood cancer that starts in the bone marrow and leads to the overproduction of abnormal white blood cells. It develops slowly over time and is considered a chronic leukemia. These abnormal cells can accumulate in the blood and crowd out healthy blood cells, affecting the body’s ability to fight infections, carry oxygen, and control bleeding. CML is strongly associated with a specific genetic abnormality known as the Philadelphia Chromosome, which drives the uncontrolled growth of leukemia cells. What Happens in the Body In CML, a genetic change in bone marrow stem cells creates the Philadelphia chromosome, which produces an abnormal protein (BCR-ABL). This protein acts as a constantly active signal that tells cells to grow and divide uncontrollably.

Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a type of blood cancer that develops when bone marrow cells acquire a specific genetic mutation, most commonly the Philadelphia chromosome (a fusion of chromosomes 9 and 22 creating the BCR-ABL gene), which causes uncontrolled production of abnormal white blood cells. CML typically progresses through three phases: a chronic phase (which may last for years with few or mild symptoms), an accelerated phase with worsening symptoms and harder-to-control blood counts, and a blast phase (also called blast crisis) that resembles acute leukemia. Early symptoms are often subtle or absent, but as the disease progresses, patients may experience fatigue, weakness, unintentional weight loss, night sweats, fever without infection, abdominal fullness or pain from an enlarged spleen, easy bruising or bleeding, and bone pain.

Chronic Obstructive Pulmonary Disease

Chronic Urticaria (Hives)

Cirrhosis

Cirrhosis is a serious liver condition that develops when healthy liver tissue is replaced by scar tissue, gradually reducing the liver’s ability to filter toxins, produce proteins, and regulate metabolism. It is a major cause of abnormal liver tests, low albumin levels, and unexplained fatigue—and is often first detected through routine blood work before symptoms appear. As scar tissue builds, it disrupts normal liver architecture and blood circulation, impairing overall liver function. This process typically develops over years of chronic liver injury and represents the final stage of many forms of liver disease. Disease Progression Cirrhosis progresses through two main stages: Compensated cirrhosis: The liver is significantly scarred but still able to perform most of its functions. Many individuals have no symptoms, and the condition is often identified through abnormal lab markers. Decompensated cirrhosis: Liver function declines, leading to complications such as fluid buildup, bleeding, and cognitive changes. This stage carries a higher risk of hospitalization and mortality.

CNS Lymphoma

Colorectal Cancer

Common variable immunodeficiency (CVID)

Community-Acquired Pneumonia

Congenital Adrenal Hyperplasia (CAH)

Congenital Syphilis

Conn's syndrome

Conn's syndrome, also known as primary hyperaldosteronism, is a health condition characterized by the overproduction of the hormone aldosterone by the adrenal glands, which are located above the kidneys. Aldosterone plays a crucial role in regulating blood pressure by controlling the balance of sodium and potassium in the body. When too much aldosterone is produced, it causes the kidneys to retain sodium and lose potassium, leading to increased water retention, high blood pressure (hypertension), and low potassium levels (hypokalemia). Common symptoms of Conn's syndrome include persistent high blood pressure that is difficult to control, muscle weakness, fatigue, headaches, excessive thirst, and frequent urination. In some cases, patients may also experience tingling or numbness due to the low potassium levels. Diagnosis typically involves blood tests to measure aldosterone and renin levels, as well as imaging studies like CT scans to identify any abnormalities in the adrenal glands.

Constipation

COPD / Chronic Lung Disease

Coronary Artery Disease (CAD)

COVID-19

Crigler-Najjar syndrome

Crigler-Najjar syndrome is a rare genetic disorder that affects the body's ability to process bilirubin, a yellow pigment formed by the breakdown of red blood cells. This condition is named after the researchers John Fielding Crigler and Victor Assad Najjar, who first described it in the mid-20th century. Crigler-Najjar syndrome is characterized by a high level of unconjugated bilirubin in the blood, leading to jaundice (a yellowing of the skin and eyes). The condition is caused by mutations in the UGT1A1 gene, which is responsible for encoding an enzyme essential for converting the fat-soluble form of bilirubin into a water-soluble form that can be excreted from the body. Crigler-Najjar syndrome is divided into two types based on its severity and underlying genetic mutations. Type 1 is the more severe form, with little to no enzyme activity, leading to very high levels of bilirubin in the blood from a young age.

Crohn's Disease

Crohn's Disease is a chronic inflammatory bowel disease (IBD) characterized by transmural inflammation, which can occur in any part of the gastrointestinal tract, from the mouth to the anus, though it most frequently affects the terminal ileum and the beginning of the colon. Unlike Ulcerative Colitis, another form of IBD, Crohn's Disease often presents with patchy areas of inflammation, with segments of normal tissue in between, a pattern known as skip lesions. The etiology of Crohn's Disease is complex and multifactorial, involving genetic predisposition, environmental factors, an abnormal immune response, and alterations in the gut microbiome. Symptoms of Crohn's Disease are diverse and can include abdominal pain, persistent diarrhea, rectal bleeding, weight loss, and fatigue. The disease can also manifest extraintestinal symptoms, such as arthritis, skin disorders, and eye inflammation. The transmural nature of the inflammation in Crohn's Disease can lead to complications like strictures, fistulas, and abscesses.

Cryoglobulinemia

Cushing's syndrome

Cushing's syndrome is a medical condition that arises when your body is exposed to high levels of the hormone cortisol for a long period of time. Cortisol, often referred to as the "stress hormone," is produced in the adrenal glands located above your kidneys and plays a crucial role in managing various functions in your body, including regulating metabolism, reducing inflammation, and helping the body respond to stress. However, when too much cortisol circulates in the bloodstream, it can lead to a range of symptoms and health issues that characterize Cushing's syndrome. The symptoms of Cushing's syndrome can be varied and affect different parts of the body. Common signs include weight gain, particularly around the midsection and upper back, a rounded face often described as a "moon face," and pink or purple stretch marks on the skin. People with Cushing's syndrome may also experience high blood pressure, bone loss leading to fractures, and changes in skin texture and appearance, such as acne or thinner skin that bruises easily.

Cysticercosis

Cysticercosis: Causes, Symptoms, Treatment What is Cysticercosis Human cysticercosis is a parasitic infection caused by the larvae of the pork tapeworm, Taenia solium. You get it when you eat the eggs from the tapeworm through contaminated food or water and develop cysticercosis. Once inside the body the eggs hatch and the larvae travel through the blood stream and embed themselves in muscles, skin, eyes and the central nervous system. When they infect the brain it’s called neurocysticercosis which is the most severe and can cause neurological symptoms. Lifecycle of Taenia Solium The lifecycle of Taenia solium involves both human and pig hosts. The solium eggs are passed out in the feces of an infected human. When pigs eat these eggs they hatch into larvae which then penetrate the intestinal wall and migrate to various tissues and form cysts. Humans can get infected by eating undercooked pork with these cysts and the larvae will develop into adult tapeworms in the intestine.

Cystitis (Bladder Infection)

Cytomegalovirus (CMV)

Cytomegalovirus (CMV), a member of the Herpesviridae family, is a prevalent pathogen with a wide-ranging impact on human health. Characterized by its ability to establish lifelong latent infections with periodic reactivations, CMV primarily infects epithelial and endothelial cells, as well as leukocytes. It is transmitted through bodily fluids like saliva, urine, blood, and semen, making it highly communicable in close-contact settings. Clinically, CMV can be asymptomatic in healthy individuals, but it poses significant risks in immunocompromised populations, such as HIV/AIDS patients, organ transplant recipients, and newborns with congenital CMV infection. In these high-risk groups, CMV can cause severe manifestations, including retinitis, pneumonitis, and gastrointestinal disease. Congenital CMV, acquired in utero, is a leading cause of sensorineural hearing loss and neurodevelopmental disorders in children. Diagnosis of CMV infection is typically through polymerase chain reaction (PCR) testing, detecting viral DNA, or by serological methods assessing specific CMV antibodies.

Deep vein thrombosis

Deep Vein Thrombosis (DVT)

Dehydration

Understanding Dehydration: Symptoms, Causes, and Biomarkers Dehydration is a common yet often overlooked health condition that occurs when the body loses more fluids than it takes in. This imbalance disrupts the normal functions of cells and organs, potentially leading to serious health complications. Symptoms of dehydration can range from mild to severe, including dry mouth, fatigue, dizziness, dark urine, and in extreme cases, rapid heartbeat and confusion. Recognizing these signs early is crucial to prevent the condition from escalating. One of the primary causes of dehydration is inadequate fluid intake, especially during hot weather or intense physical activity. However, it can also result from illnesses that cause vomiting, diarrhea, or excessive sweating. Certain populations, such as infants, the elderly, and individuals with chronic illnesses, are at a higher risk of becoming dehydrated. Therefore, maintaining proper hydration is essential for overall health and well-being. To diagnose and monitor dehydration, several biomarkers can be tested.

Dementia

Dermatitis Herpetiformis

What is Dermatitis Herpetiformis? Dermatitis herpetiformis (DH), sometimes called Duhring's disease, is a chronic, intensely itchy blistering skin rash that represents the cutaneous (skin) manifestation of celiac disease. It's often described as "celiac disease of the skin." The condition affects approximately 10-25% of people with celiac disease, though many people with dermatitis herpetiformis have minimal or no digestive symptoms, making the skin rash their primary or only sign of gluten sensitivity. Despite its name, dermatitis herpetiformis has nothing to do with herpes viruses. The "herpetiformis" refers to the grouped or clustered appearance of the blisters, which resembles herpes skin lesions. The condition typically begins in adulthood, most commonly between ages 30-40, though it can occur at any age. It affects men slightly more often than women (ratio of about 3:2) and is more common in people of Northern European descent.

Dermatomyositis

Diabetes

Diabetes is a common, manageable condition characterized by elevated blood sugar levels, which can affect individuals of all ages. It arises when the pancreas does not produce sufficient insulin or when the body cannot effectively use the insulin it produces. The most prevalent form of diabetes is Type 2, where the body either resists the effects of insulin or doesn't produce enough, often developing in adults but also occurring in children. Other forms include Type 1 diabetes, an autoimmune disease leading to the destruction of insulin-producing cells, prediabetes, gestational diabetes, and other less common types like Type 3c and MODY. Symptoms of diabetes can range from increased thirst and frequent urination to unexplained weight loss and blurred vision, varying in intensity across the different types. Causes include insulin resistance, autoimmune responses, genetic mutations, and hormonal imbalances, with complications potentially involving heart disease, nerve damage, and kidney failure among others.

Diabetes Insipidus

Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is a life-threatening metabolic emergency that occurs when insulin levels are too low for the body to use glucose properly, leading to excess ketone production and a high anion gap metabolic acidosis. It is often first recognized on blood tests showing high glucose, elevated ketones, and low bicarbonate, sometimes before symptoms become severe. DKA develops when insulin deficiency prevents cells from using glucose for energy. In response, the body breaks down fat, producing ketones such as beta-hydroxybutyrate and acetoacetate. As these ketones accumulate, they cause metabolic acidosis and disrupt fluid and electrolyte balance. What Causes Diabetic Ketoacidosis? The most common triggers of DKA are infection, missed insulin doses, and new-onset diabetes.

Diabetic Nephropathy

Diffuse Cutaneous Systemic Sclerosis

Disseminated Intravascular Coagulation (DIC)

Disseminated Intravascular Coagulation (DIC) is a complex, potentially life-threatening condition characterized by the abnormal activation of the body's clotting mechanisms, which can lead to the simultaneous occurrence of widespread clotting and bleeding. This paradoxical situation arises because the clotting process consumes large amounts of clotting factors and platelets, leading to their depletion, which then results in bleeding. DIC can occur as a secondary complication of various underlying conditions that affect the body’s ability to regulate clotting, such as severe infections (sepsis), significant trauma, cancers, obstetric emergencies (like amniotic fluid embolism), and certain blood disorders. Diagnosing DIC is challenging due to its varied manifestations and the presence of underlying diseases. It involves a combination of clinical assessment and laboratory tests.

Drug Hypersensitivity Reaction

Drug-Induced Liver Injury

Drug-induced lupus erythematosus (DILE)

WHAT IS DRUG-INDUCED LUPUS ERYTHEMATOSUS? Drug-induced lupus erythematosus (DILE) is a lupus-like condition triggered by certain prescription medicines. It causes symptoms similar to systemic lupus erythematosus (SLE)—the more common form of lupus—but usually stays milder and almost always improves after the offending drug is stopped. Unlike lupus that develops on its own (sometimes called idiopathic or spontaneous lupus), drug-induced lupus is directly caused by taking specific medications. The good news: once you stop the medication, symptoms typically go away within weeks to months. DILE is generally milder than spontaneous lupus. It rarely affects the kidneys or brain—two of the most serious problems that can happen with regular lupus.

Dubin-Johnson syndrome

Dubin-Johnson Syndrome is a rare, inherited disorder characterized by chronic jaundice. This condition stems from the liver's inability to properly secrete certain types of bilirubin into the bile. Bilirubin is a yellow pigment that is produced by the breakdown of red blood cells and is normally processed by the liver and excreted through bile. However, in individuals with Dubin-Johnson Syndrome, a genetic mutation affects the liver's transport proteins, leading to the accumulation of conjugated bilirubin in the liver, which then spills over into the bloodstream, causing the skin and whites of the eyes to appear yellow. This syndrome is often diagnosed in adolescence or early adulthood, though it can be identified at any age, including infancy. Remarkably, aside from the chronic jaundice, many individuals with Dubin-Johnson Syndrome experience no other symptoms and lead normal, healthy lives. In some cases, the jaundice may become more pronounced during times of illness, stress, or pregnancy.

Dysautonomia

Understanding Dysautonomia: Symptoms, Diagnosis, and Treatment Dysautonomia is a complex and often misunderstood condition that affects the autonomic nervous system, which controls involuntary bodily functions such as heart rate, blood pressure, digestion, and temperature regulation. This disorder can manifest in various forms, including Postural Orthostatic Tachycardia Syndrome (POTS), Neurocardiogenic Syncope, and Multiple System Atrophy, each presenting with unique challenges. Understanding dysautonomia is crucial for effective management and improving the quality of life for those affected by this condition. Symptoms of Dysautonomia The symptoms of dysautonomia are diverse and can vary greatly from person to person. Common signs include dizziness, fainting (syncope), rapid heart rate (tachycardia), and fluctuations in blood pressure. Patients may also experience gastrointestinal issues such as nausea, bloating, and constipation, as well as problems with temperature regulation, leading to excessive sweating or an inability to sweat.

Dysbiosis

Dysbiosis is a term that refers to an imbalance in the microbial communities that reside in our bodies, particularly in the gut. The human body hosts trillions of microorganisms, collectively known as the microbiome, which play a crucial role in maintaining overall health. When the balance of these beneficial and harmful microorganisms is disrupted, it can lead to dysbiosis, potentially triggering a range of health issues. What is Dysbiosis? Dysbiosis occurs when there is a shift in the balance of microorganisms in the gut, where beneficial bacteria are either diminished or overwhelmed by harmful pathogens. The gut microbiome is essential for digestion, immune function, and even mental health. When this balance is disturbed, the result can be a range of digestive and systemic health problems. A healthy gut microbiota consists of a wide variety of bacteria, fungi, and viruses that work in harmony to keep the digestive system functioning optimally. However, when this delicate ecosystem is disrupted, either by poor diet, medication, or disease, dysbiosis can occur.

Early Pregnancy Loss

Elevated PSA

Encephalitis

Endometrial Hyperplasia

Endometrial hyperplasia is a condition characterized by abnormal thickening of the endometrium (the lining of the uterus) due to prolonged exposure to estrogen without adequate progesterone. It is a common gynecologic condition and is considered a precancerous state in certain forms, particularly when cellular atypia is present. The condition most often occurs in women with hormonal imbalance — especially those experiencing anovulation, perimenopause, or obesity. Because progesterone normally counteracts estrogen’s proliferative effects on the endometrium, insufficient progesterone leads to continuous endometrial growth, increasing the risk of abnormal bleeding and, in some cases, progression to endometrial cancer. Early identification and appropriate management are critical, as many cases are reversible, while others require closer surveillance or definitive treatment.

Endometriosis

Understanding Endometriosis: Symptoms, Diagnosis, and Treatment Endometriosis is a chronic health condition that affects millions of women worldwide. This condition occurs when tissue similar to the lining inside the uterus, known as the endometrium, starts to grow outside the uterus. Common sites for these growths include the ovaries, fallopian tubes, and the tissue lining the pelvis. In rare cases, endometrial tissue can spread beyond the pelvic organs. Endometriosis can cause significant pain, menstrual irregularities, and fertility issues, making it essential to understand the condition thoroughly. Symptoms of Endometriosis The symptoms of endometriosis can vary greatly among women, and some may experience severe symptoms while others have mild or no symptoms at all. The most common symptom is pelvic pain, often associated with menstrual periods. This pain can be far more intense than typical menstrual cramps and may begin before and extend several days into the period. Other symptoms include pain during intercourse, pain with bowel movements or urination, and excessive bleeding.

Eosinophilia

Eosinophilic Esophagitis

Epilepsy

Understanding Epilepsy: Symptoms, Diagnosis, and Treatment Epilepsy is a chronic neurological disorder that affects millions of people worldwide. Characterized by recurrent, unprovoked seizures, epilepsy arises from abnormal electrical activity in the brain. This condition can significantly impact daily life, making it essential to understand its symptoms, diagnostic methods, and treatment options. With the right knowledge and management strategies, individuals with epilepsy can lead fulfilling lives. Symptoms of Epilepsy The hallmark symptom of epilepsy is recurrent seizures, which can vary widely in type and severity. Seizures are categorized into focal seizures, which start in one area of the brain, and generalized seizures, which affect both sides of the brain. Symptoms of focal seizures may include unusual sensations, repetitive movements, and changes in behavior or awareness.

Epstein-Barr Virus and Infectious Mononucleosis

Epstein-Barr Virus (EBV), a widespread and persistent herpesvirus, is primarily known for causing Infectious Mononucleosis, often referred to as "Mono" or the "kissing disease." EBV, discovered in 1964, is remarkably prevalent, infecting over 90% of the global adult population. The virus is typically transmitted through bodily fluids, particularly saliva, which is why Mono has garnered its nickname. Once infected, individuals may experience a range of symptoms, including but not limited to fatigue, fever, inflamed throat, swollen lymph nodes, and an enlarged spleen. These symptoms usually manifest four to six weeks after exposure and can vary in intensity and duration. Interestingly, EBV can also remain dormant in the body and potentially reactivate later in life, though usually without symptoms. Moreover, the virus has been linked to certain types of cancers and autoimmune diseases, making its study crucial in medical research. Vaccines against EBV are currently under development, aiming to reduce the risks associated with the virus.

Erectile Dysfunction

ESBL Infection

Essential fatty acid (EFA) deficiency

Understanding Essential Fatty Acid (EFA) Deficiency Essential fatty acid (EFA) deficiency occurs when the body does not receive enough essential fatty acids, which are vital for numerous biological functions. EFAs, particularly omega-3 and omega-6 fatty acids, are critical components of cell membranes and play significant roles in inflammation regulation, brain function, and skin health. Since the human body cannot synthesize these fatty acids, they must be obtained through diet. A deficiency in EFAs can lead to a range of health problems, including impaired cognitive function, poor skin health, and immune dysfunction. This condition is often seen in individuals with specific dietary restrictions, malabsorption disorders, or those on intravenous feeding without adequate fat supplementation. Symptoms and Diagnosis of EFA Deficiency The symptoms of EFA deficiency can vary but commonly include dry, scaly skin, brittle hair, and poor wound healing.

Essential Thrombocythaemia

Essential Thrombocythemia

Essential thrombocythemia (ET) — also spelled essential thrombocythaemia — is a chronic bone marrow disorder that causes the body to produce too many platelets. It is usually first detected on a routine blood test showing a persistently high platelet count. While ET can increase the risk of blood clots, most people have few symptoms and can live a normal life expectancy with appropriate monitoring and treatment. Unlike reactive thrombocytosis — where platelet count rises temporarily in response to infection, inflammation, or iron deficiency — ET is a clonal disorder driven by an acquired genetic mutation in bone marrow stem cells. The primary treatment goal is reducing the risk of blood clot complications rather than eliminating the disease.

Estrogen Deficiency

Estrogen Dominance

Estrogen dominance refers to a state of hormonal imbalance in which estrogen activity outweighs the effects of progesterone — either due to elevated estrogen levels, insufficient progesterone, or both. It is not a formal medical diagnosis but a widely used clinical concept that helps explain a range of symptoms related to hormonal imbalance, particularly in women of reproductive age and during perimenopause. Estrogen dominance is common and often under-recognized. It can result from endogenous hormone dysregulation (such as anovulation), metabolic factors (such as obesity and insulin resistance), impaired estrogen metabolism or clearance, or exogenous estrogen exposure (including medications and environmental endocrine disruptors). Because estrogen and progesterone must function in balance to regulate the menstrual cycle, endometrial health, and ovulation, disruption of this balance can contribute to menstrual irregularities, infertility, and estrogen-driven conditions such as fibroids and endometriosis.

Familial Hypercholesterolemia

Fibromyalgia

Fibromyalgia is a chronic health condition characterized by widespread musculoskeletal pain, fatigue, and tenderness in localized areas. This disorder primarily affects muscles and soft tissues, leading to persistent pain that can vary in intensity from mild to severe. According to the Centers for Disease Control and Prevention, fibromyalgia affects about 4 million US adults, or about 2% of the adult population. The exact cause of fibromyalgia is not well understood, but it is believed to be related to abnormal levels of certain chemicals in the brain and changes in the way the central nervous system processes pain signals. Recent research published in the Journal of Pain Research suggests that neuroinflammation may play a significant role in the development of fibromyalgia. Genetic factors may also contribute, as fibromyalgia often runs in families. Additionally, triggers such as physical trauma, infections, or significant psychological stress may contribute to the onset of symptoms.

Folate Deficiency

Folate Deficiency Anemia

Frontotemporal Dementia

Functional dyspepsia

Functional Dyspepsia: Symptoms, Causes, Diagnosis, and Treatment Functional dyspepsia (FD), also known as non-ulcer dyspepsia, is a common digestive disorder affecting approximately 12% of the population in the United States. It causes persistent stomach discomfort without any detectable structural abnormalities in the upper gastrointestinal tract, leading to symptoms such as bloating, stomach pain, and fullness after eating. What is Functional Dyspepsia? Functional dyspepsia is a chronic disorder of the upper digestive tract characterized by recurring symptoms of indigestion, bloating, and stomach discomfort. Unlike other gastrointestinal conditions, such as peptic ulcers or gastroesophageal reflux disease (GERD), functional dyspepsia does not show any visible signs of damage during diagnostic testing like endoscopy. It is considered a "functional" disorder because the symptoms occur without any identifiable structural abnormalities. Functional Dyspepsia Symptoms Functional dyspepsia can present with a variety of symptoms that often come and go without a clear pattern.

Functional hypothalamic amenorrhea

G6PD Deficiency

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic disorder that affects the red blood cells, which are responsible for carrying oxygen from the lungs to the rest of the body. This condition occurs due to a mutation in the G6PD gene, which plays a crucial role in the proper functioning of red blood cells. The primary function of the G6PD enzyme is to protect the red blood cells from damage caused by certain chemicals found in foods and medications, as well as stress from infections. When there's a deficiency in this enzyme, red blood cells can break down prematurely, a condition known as hemolysis, leading to hemolytic anemia. G6PD deficiency is more common in males and is particularly prevalent in populations from Africa, the Mediterranean, the Middle East, and certain Asian countries. This pattern of prevalence is believed to be linked to the protective effect of the mutation against malaria; areas with high rates of malaria often have higher incidences of G6PD deficiency. The symptoms of G6PD deficiency can vary widely among individuals.

Gallstones

Gastritis

What is Gastritis? Gastritis refers to inflammation of the stomach lining. This condition can develop suddenly (acute gastritis) or progress slowly over time (chronic gastritis), with causes ranging from infections and medications to stress and dietary habits. Acute Gastritis: Sudden Onset of Stomach Inflammation Acute gastritis occurs when the stomach lining becomes inflamed quickly, often with sharp and noticeable symptoms. Common causes include: Medications (such as NSAIDs like ibuprofen or aspirin) Infections (bacterial or viral) Psychological stress (emotional strain can impact stomach health) Dietary triggers (high intake of fatty, spicy, or highly processed foods) Food contamination (ingesting contaminated food or drinks) Acute gastritis episodes are typically short-lived but can be intense, often improving with the removal of the triggering factor. Chronic Gastritis: Long-Term Stomach Inflammation Chronic gastritis is a persistent, ongoing inflammation of the stomach lining. Unlike acute cases, symptoms can last for months or even years.

Genital Herpes

Genital herpes is a chronic viral infection caused by HSV-1 or HSV-2, transmitted through sexual contact. While HSV-2 is more commonly associated with genital infections, HSV-1 is increasingly responsible due to oral-genital transmission. Symptoms may include painful blisters or ulcers in the genital or anal area, itching, burning, and discomfort during urination. The initial outbreak is often the most severe and may include flu-like symptoms such as fever and swollen lymph nodes. After the first infection, the virus remains dormant and can reactivate periodically. Recurrences are typically milder and less frequent over time. Many people with genital herpes have no symptoms but can still transmit the virus through asymptomatic shedding. There is no cure, but antiviral medications can: Reduce outbreak frequency Shorten symptom duration Lower transmission risk to partners Genital herpes is manageable, and most individuals live normal, healthy lives with minimal impact.

Giant Cell Arteritis

Gilbert disease

Gilbert syndrome, often referred to simply as Gilbert's syndrome, is a mild liver disorder characterized by an elevated level of bilirubin in the bloodstream. This condition is typically harmless and often goes undiagnosed due to its generally asymptomatic nature. Individuals with Gilbert's syndrome have a reduced ability to process bilirubin, a yellowish substance produced by the breakdown of red blood cells. While the condition is inherited and affects approximately 3% to 12% of the population, many people with Gilbert's syndrome may never realize they have it. One of the hallmark features of Gilbert's syndrome is jaundice, which is a yellowing of the skin and the whites of the eyes that occurs when bilirubin accumulates in the blood. However, jaundice associated with Gilbert's syndrome is usually mild and may only be noticeable during periods of exertion, stress, fasting, or illness. Besides jaundice, Gilbert's syndrome rarely causes any other symptoms and does not lead to serious health problems.

Gliomas

What are gliomas? Gliomas are cancerous brain tumors that start in glial cells. These are the supporting cells of the brain and the spinal cord. Some types of gliomas grow faster than others. Glioma is a growth of cells that starts in the brain or spinal cord. The cells in a glioma look similar to healthy brain cells called glial cells. Glial cells surround nerve cells and help them function. As a glioma grows it forms a mass of cells called a tumor. The tumor can grow to press on brain or spinal cord tissue and cause symptoms. Symptoms depend on which part of the brain or spinal cord is affected. There are many types of glioma. Some grow slowly and are not considered to be cancers. Others are considered cancerous. Another word for cancerous is malignant. Malignant gliomas grow quickly and can invade healthy brain tissue. Some types of glioma happen mostly in adults. Others happen mostly in kids. In the United States, there are six cases of gliomas diagnosed per 100,000 people every year. Gliomas are very diffusely infiltrative tumors that affect the surrounding brain tissue.

Glomerulonephritis

Understanding Glomerulonephritis: Causes, Symptoms, Diagnosis, and Treatment Glomerulonephritis is a kidney condition affecting the glomeruli, tiny filtering units within the kidneys. This serious health issue impacts the kidneys' ability to filter waste and excess fluids from the blood. Understanding its causes, symptoms, diagnosis, and treatment options is crucial for maintaining kidney health and managing this condition effectively. What is Glomerulonephritis? Glomerulonephritis is characterized by inflammation of the glomeruli, small looped blood vessels inside the kidneys that filter blood. When inflamed, their filtering ability is compromised, leading to various health problems, including kidney damage.Two main types exist: Acute Glomerulonephritis: Develops suddenly, often following infections. Chronic Glomerulonephritis: Progresses slowly over years, potentially leading to long-term kidney damage. Prevalence Glomerulonephritis affects approximately 1 in 10,000 people worldwide, with higher rates in certain populations.

Gout

Graves' Disease

Graves' Disease is an autoimmune disorder that leads to an overactive thyroid gland, or hyperthyroidism. This condition occurs when the immune system mistakenly attacks the thyroid gland, causing it to produce excessive amounts of thyroid hormones. These hormones are crucial regulators of the body's metabolic rate, influencing various bodily functions. The precise cause of Graves' Disease remains unknown, but factors like genetics, environmental triggers, and stress are believed to play a role in its development. Diagnosing Graves' Disease involves a comprehensive evaluation, including a physical examination, patient history, blood tests to measure levels of thyroid hormones and thyroid-stimulating hormone (TSH), and sometimes, imaging tests. A key hallmark of Graves' Disease is the presence of specific antibodies in the blood that stimulate the thyroid gland to produce too much hormone. Additionally, a radioactive iodine uptake test can help determine if the gland is overactive, a common indicator of Graves' Disease.

Gynaecomastia

Gynecomastia

Gynecomastia is the benign enlargement of glandular breast tissue in males, resulting from an imbalance between estrogen and androgen action at the breast tissue level. It is the most common breast condition in men and boys, affecting up to 70% of adolescent males during puberty and a significant proportion of older men — yet it remains widely misunderstood, underinvestigated, and undertreated. Gynecomastia is not simply fat accumulation in the chest — a distinction that matters both clinically and for the patient. True gynecomastia involves the proliferation of ductal and stromal breast tissue driven by estrogenic stimulation, producing a firm, disc-like mass of glandular tissue beneath the nipple that is distinct from the soft, diffuse adipose tissue seen in pseudogynecomastia (lipomastia). While gynecomastia is benign, it can be a sign of an underlying hormonal disorder, systemic disease, medication effect, or — rarely — malignancy. A thorough evaluation is always warranted when gynecomastia is newly detected or unexplained, particularly in adult men.

Hashimoto's disease

Hashimoto's disease, also known as Hashimoto's thyroiditis, is an autoimmune disorder where the immune system attacks the thyroid gland, leading to chronic inflammation and an underactive thyroid gland, or hypothyroidism. This condition can lead to a wide array of symptoms and significantly impact an individual's quality of life if left untreated. The thyroid, a small gland located at the base of the neck, plays a crucial role in regulating metabolic processes in the body through the release of hormones. When Hashimoto's disease impairs its function, the body's metabolism slows down, leading to symptoms such as fatigue, weight gain, sensitivity to cold, constipation, dry skin, hair loss, muscle weakness, and depression. Additionally, individuals may experience swelling at the front of the neck due to an enlarged thyroid gland, known as a goiter. Diagnosing Hashimoto's disease involves a combination of clinical evaluation, blood tests, and sometimes imaging studies.

Heart Failure

Helicobacter pylori (H. pylori) infection

Helicobacter pylori (H. pylori) infection is a common condition that affects the stomach lining and is a leading cause of peptic ulcers and gastric inflammation (gastritis). This bacteria can be silently lurking in the digestive tract, often without causing symptoms, but it's a major culprit behind stomach pain, bloating, and discomfort. If left untreated, H. pylori infection can lead to more serious health issues, including stomach cancer. It's usually contracted in childhood and can be spread through contaminated food, water, or close contact with an infected person. The good news is that H. pylori infection is treatable with a combination of antibiotics and medications to reduce stomach acid and heal the stomach lining. It's important to seek medical advice if you're experiencing symptoms like persistent stomach discomfort, as early detection and treatment can prevent complications. Understanding H. pylori is the first step towards managing its impact on health, ensuring individuals can lead a healthier, more comfortable life.

Hematuria

Hemochromatosis

Hemochromatosis: Causes, Symptoms, Diagnosis, and Treatment Hemochromatosis is a genetic disorder that leads to iron overload in the body. This excess iron can cause serious damage to vital organs, such as the liver, heart, pancreas, and joints. If left untreated, hemochromatosis can result in conditions like liver disease, diabetes, heart issues, and arthritis. Here’s everything you need to know about this condition, including types, symptoms, diagnosis, treatment, and management tips. What is Hemochromatosis? Hemochromatosis can be thought of as the body absorbing too much iron, like a sponge that can't stop soaking up water. This extra iron is stored in organs, which can eventually lead to significant health problems. Types of Hemochromatosis There are two main types of hemochromatosis: Primary Hemochromatosis (Hereditary) Caused by mutations in the HFE gene, specifically the C282Y and H63D variants. Inherited in an autosomal recessive pattern. Non-HFE types (10-15% of cases) involve mutations in other genes, like HJV and HAMP.

Hemoglobinopathy

Hemolytic Anemia

Hemolytic anemia is a blood disorder that typically happens when your red blood cells break down or die faster than your body can replace them with new blood cells. Hemolytic anemia can develop quickly or slowly, and it can be mild or serious. People may develop hemolytic anemia by inheriting genetic conditions that cause anemia, certain infections and certain medications. Sometimes, people have mild hemolytic anemia symptoms that go away after treatment. Many times, healthcare providers can cure hemolytic anemia after finding out what caused the condition. Left untreated, however, severe hemolytic anemia can cause serious heart trouble. Red blood cells normally live for about 120 days. When they break down or die sooner than that, your bone marrow doesn’t have time to produce enough new red blood cells, leaving you with a low red blood cell count. Other anemia types may occur when: - Injury or illness causes excessive bleeding that drains your red blood cell supply faster than your body can replace it.

Hemophilia A

Hepatitis

Hepatitis A (Acute HAV Infection)

Hepatitis A is an acute viral infection of the liver caused by the hepatitis A virus (HAV). It is one of the most common vaccine-preventable infections worldwide, spread primarily through contaminated food or water or close contact with an infected person. Unlike hepatitis B and C, hepatitis A does not cause chronic liver disease — almost everyone recovers fully, and infection provides lifelong immunity. Illness ranges from very mild or completely asymptomatic — particularly in young children — to a debilitating illness lasting several months in adults. Acute liver failure is rare but possible, particularly in people with pre-existing liver disease or those who are older. How hepatitis A spreads HAV is transmitted by the fecal-oral route — meaning the virus is shed in the stool of infected people and enters a new host through ingestion.

Hepatitis B (Acute)

Hepatitis B (Chronic)

Hepatocellular carcinoma

Hereditary Angioedema (HAE) Type I

What is Hereditary Angioedema (HAE) Type I? Hereditary Angioedema (HAE) Type I is a rare, inherited genetic disorder that causes recurrent episodes of severe swelling (angioedema) in various parts of the body. These episodes most commonly affect the face, lips, throat, abdomen, limbs, and genitals. Swelling can be painful, unpredictable, and, in some cases, life-threatening—especially when it involves the airways. HAE affects approximately 1 in 50,000 people worldwide. Type I is the most common form, accounting for about 85% of all HAE cases. The disorder is inherited in an autosomal dominant manner, meaning a child has a 50% chance of inheriting the condition if one parent is affected. What Causes HAE Type I? HAE Type I is caused by a genetic mutation that leads to low levels of a protein called C1 esterase inhibitor (C1-INH). This protein helps regulate inflammation by controlling the complement system and the production of bradykinin—a chemical that increases blood vessel permeability and causes fluid to leak into surrounding tissues.

Hereditary Complement Deficiency

Hereditary Hemochromatosis

Hereditary Spherocytosis

Herpes Simplex Virus Infection

Herpes simplex virus (HSV) infection is a widespread condition caused by two closely related viruses: HSV-1 and HSV-2. HSV-1 commonly causes oral herpes (cold sores), while HSV-2 typically causes genital herpes, although both types can infect either location. After initial infection, HSV establishes latency in nerve cells and remains in the body for life. Periodic reactivation can lead to recurrent symptoms or asymptomatic viral shedding. Most people with HSV infection experience: No symptoms Mild, occasional outbreaks Unrecognized infection When symptoms occur, they may include blisters, ulcers, tingling sensations, and localized pain. HSV is transmitted through direct skin-to-skin or mucosal contact. It is most contagious during active outbreaks but can still spread without visible symptoms. Diagnosis is typically made through: PCR testing of active lesions Type-specific IgG antibody testing (for past exposure) Management focuses on symptom control and reducing transmission risk. Antiviral medications are effective and widely used.

Herpes Simplex Virus Type 1 (HSV-1)

Herpes Simplex Virus Type 2 (HSV-2) infection

Hirsutism

Hirsutism is a health condition characterized by the growth of excessive or unwanted hair on a woman's face, chest, and back, following a pattern of male hair distribution. This condition is more than a cosmetic concern; it can signify underlying health issues, often linked to an imbalance of male hormones, known as androgens. Common in women, hirsutism is frequently associated with conditions like polycystic ovary syndrome (PCOS), which can affect hormonal balance and lead to other symptoms such as irregular menstrual cycles, acne, and obesity. Diagnosing hirsutism involves a comprehensive evaluation, including a detailed medical history to understand any underlying causes or contributing factors such as medication use or genetic predisposition. Physicians may conduct physical examinations to assess hair growth patterns and use blood tests to measure hormone levels, helping to identify or rule out specific conditions like PCOS, adrenal gland disorders, or other hormonal imbalances.

HIV/AIDS

Hodgkin Lymphoma

Homocystinuria

Hormonal Imbalance

Hormone Replacement Therapy (Monitoring)

Hormone Replacement Therapy (HRT) monitoring refers to the structured evaluation of hormone levels, symptom response, and safety markers in individuals receiving exogenous hormones — most commonly estrogen, progesterone, and/or testosterone. It is an essential component of care to ensure that therapy is both effective (symptom control) and safe (minimizing long-term risk). HRT is widely used in multiple clinical contexts, including menopause management, hypogonadism in men, gender-affirming care, and certain endocrine disorders. Because exogenous hormones alter the body’s natural regulatory systems, ongoing monitoring is required to optimize dosing, avoid under- or over-treatment, and detect potential adverse effects early. A structured monitoring approach — combining lab testing, clinical symptoms, and individualized targets — allows for precise, personalized hormone management over time.

Hypereosinophilic Syndrome

Hyperinsulinemia

Hyperlipidemia / High Cholesterol

Hyperlipidemia, commonly known as high cholesterol, is a condition characterized by elevated levels of lipids (fats) in the blood, including cholesterol and triglycerides. Cholesterol exists in several forms: low-density lipoprotein (LDL or "bad" cholesterol) which deposits in artery walls and contributes to plaque buildup, high-density lipoprotein (HDL or "good" cholesterol) which helps remove excess cholesterol from the bloodstream, and very low-density lipoprotein (VLDL) which carries triglycerides. High cholesterol typically causes no symptoms and is often discovered only through routine blood tests, though severely elevated levels can sometimes cause physical signs such as yellowish deposits around the eyes (xanthelasma) or on tendons (xanthomas). The condition develops due to a combination of genetic factors (familial hypercholesterolemia), diet high in saturated fats and trans fats, obesity, lack of physical activity, smoking, diabetes, hypothyroidism, and certain medications.

Hyperoxaluria

Hyperoxaluria is a complex health condition characterized by an excessive excretion of oxalate in the urine. Oxalate is a natural chemical found in the body, and it's also present in certain foods. When too much oxalate is present in the urine, it can lead to kidney stones and other kidney diseases. This condition can occur on its own (primary hyperoxaluria) or as a result of another disease or dietary factors (secondary hyperoxaluria). Primary hyperoxaluria is a rare, inherited condition caused by a genetic mutation that leads to the overproduction of oxalate by the liver. It is further divided into three types: Type 1, Type 2, and Type 3, each resulting from different genetic mutations affecting specific enzymes. Type 1 is the most common and severe form, potentially leading to kidney failure at a young age if left untreated.

Hyperparathyroidism

Hyperparathyroidism is a condition where the parathyroid glands in the neck produce too much parathyroid hormone (PTH), which regulates calcium levels in the body. It's mainly classified into two types: primary and secondary. Primary hyperparathyroidism, more common, occurs when one or more of the parathyroid glands become overactive, often due to a benign tumor, leading to high calcium levels in the blood. This can cause symptoms like fatigue, bone pain, kidney stones, and mood changes. Secondary hyperparathyroidism, typically caused by chronic kidney disease or vitamin D deficiency, happens when the body's low calcium levels trigger the parathyroid glands to produce more PTH. In both types, diagnosis involves blood tests to check calcium and PTH levels, and sometimes imaging tests to examine the glands. Treatment depends on the cause and severity, ranging from regular monitoring to surgery for removing overactive glands in primary hyperparathyroidism or addressing the underlying cause in secondary hyperparathyroidism.

Hyperprolactinemia

Hyperprolactinemia: Causes, Symptoms, Diagnosis, and Treatment Hyperprolactinemia is a condition characterized by abnormally high levels of prolactin in the blood. Prolactin is a hormone produced by the pituitary gland, primarily responsible for stimulating breast milk production after childbirth. However, elevated prolactin levels can occur in both men and women who are not pregnant or breastfeeding, leading to various health issues. Causes The most common causes of hyperprolactinemia include: Pituitary tumors (prolactinomas) 1, 4 Certain medications, such as those for high blood pressure, depression, and nausea 1, 6 Hypothyroidism 5 Chronic kidney or liver conditions 4 Chest wall injuries or irritation 4 Symptoms Symptoms of hyperprolactinemia can vary between men and women: In women: Menstrual irregularities or absence of periods 1, 2 Infertility 2, 4 Galactorrhea (milk production when not pregnant or breastfeeding) 1, 4 Decreased libido 4 Vaginal dryness 1 In men: Decreased libido 4 Erectile dysfunction 4 Infertility 4 Gynecomastia (enlarged breast tissue) 4 Reduced body hair and

Hypertension (High Blood Pressure)

Hypertension, commonly known as high blood pressure, is a chronic medical condition in which the force of blood against artery walls is consistently elevated, potentially causing damage to blood vessels and organs over time. Blood pressure is measured in millimeters of mercury (mmHg) and recorded as two numbers: systolic pressure (the higher number, measuring pressure when the heart beats) over diastolic pressure (the lower number, measuring pressure when the heart rests between beats). Normal blood pressure is defined as less than 120/80 mmHg, while hypertension is diagnosed when readings consistently measure 130/80 mmHg or higher. The condition is often called the "silent killer" because it typically produces no symptoms until it has caused significant damage, though some people may experience headaches, shortness of breath, nosebleeds, or dizziness with severely elevated blood pressure.

Hyperthyroidism

Hypertriglyceridemia

Hypoalbuminemia

Hypoalbuminemia—low levels of albumin in the blood—is one of the most common reasons for reduced total protein on a blood test. It can reflect problems with the liver, kidneys, nutrition, or chronic inflammation, and often appears before any obvious symptoms develop. Albumin is the main protein in the bloodstream, produced by the liver. It helps maintain fluid balance, transports hormones and medications, and plays a key role in overall metabolic function. As albumin levels drop, the body loses some of its ability to keep fluid within blood vessels, leading to fluid buildup in tissues and other systemic effects. What Causes Low Albumin Levels? Hypoalbuminemia can result from several underlying mechanisms: Reduced production (liver-related): Chronic liver disease (e.g., cirrhosis) Acute liver injury Increased loss: Kidney disease (e.g., nephrotic syndrome) Protein-losing enteropathy Inflammatory bowel disease Severe burns or skin loss Inflammation and illness: Chronic inflammation or infection Critical illness or trauma Poor intake or absorption: Malnutrition Malabsorption syndromes

Hypochlorhydria (Low Stomach Acid)

Hypochromic Anemia

Hypogammaglobulinemia

Hypogammaglobulinemia is an immune system disorder characterized by low levels of immunoglobulins (antibodies) in the blood. This deficiency weakens the body's ability to fight infections. Causes of Hypogammaglobulinemia Hypogammaglobulinemia can be classified as either primary (genetic) or secondary (acquired): Primary Causes Common Variable Immunodeficiency (CVID) X-linked Agammaglobulinemia (XLA) Severe Combined Immunodeficiency (SCID) Wiskott-Aldrich Syndrome Secondary Causes Blood Cancers (e.g., chronic lymphocytic leukemia, lymphoma) HIV Infection Medications (e.g., corticosteroids, chemotherapy drugs) Malnutrition Protein-losing Conditions Symptoms The primary symptom of hypogammaglobulinemia is an increased vulnerability to infections.

Hypogonadism

Hypogonadism: Causes, Symptoms, Diagnosis, and Treatment Introduction to Hypogonadism Hypogonadism is a condition in which the body's sex glands—testes in men and ovaries in women—produce little to no sex hormones. In men, this results in a deficiency of testosterone, crucial for developing male characteristics, libido, and sperm production. In women, it leads to insufficient estrogen and progesterone, vital for regulating menstruation and fertility. This condition can occur at any age and significantly impacts both physical and emotional well-being. Beyond reproductive health, hypogonadism affects overall health, influencing muscle mass, bone density, energy levels, and mental health. Understanding its causes, symptoms, and treatment options is essential for effective management. Types of Hypogonadism Hypogonadism is categorized into two primary types: primary hypogonadism and secondary hypogonadism, each with distinct causes. Primary Hypogonadism This type occurs when the sex glands themselves malfunction due to injury, disease, or congenital issues.

Hyponatremia

Hypophosphatasia

Hypopituitarism

Hypothalamic Amenorrhea

Hypothalamic amenorrhea (HA) is the absence of menstrual periods caused by suppression of the hypothalamic-pituitary-ovarian (HPO) axis — the hormonal signaling chain that governs the menstrual cycle. It is one of the most common causes of secondary amenorrhea (absence of periods in a woman who has previously menstruated) in reproductive-age women, accounting for approximately 30–35% of cases. Unlike conditions where the ovaries themselves fail (as in premature ovarian insufficiency), hypothalamic amenorrhea is a functional disorder — the ovaries are structurally intact and capable of normal function, but the brain has effectively switched off the reproductive system in response to perceived threat. The hypothalamus interprets chronic energy deficit, excessive exercise, psychological stress, or a combination of these as conditions too dangerous for reproduction, and suppresses the hormonal signals that initiate ovulation. This makes HA both highly reversible — the reproductive axis can be fully restored in most women — and a window into the body's broader physiological stress state.

Hypothyroidism

Overview Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormones to meet the body’s needs. Thyroid hormones—primarily thyroxine (T4) and triiodothyronine (T3)—play a critical role in regulating metabolism, energy production, temperature control, heart function, and brain health. Hypothyroidism is commonly identified through an elevated Thyroid-Stimulating Hormone (TSH) level on blood testing and is one of the most frequent endocrine disorders worldwide. What the Thyroid Does The thyroid is a small, butterfly-shaped gland located at the front of the neck. It produces hormones that influence nearly every organ system, including: Metabolic rate and energy expenditure Body temperature regulation Heart rate and cardiovascular function Digestion and gut motility Brain function and mood Growth, fertility, and pregnancy health When thyroid hormone levels are too low, many of these systems slow down. Causes of Hypothyroidism Hypothyroidism can develop for several reasons.

Hypoxemia

IgA Nephropathy (Berger's Disease)

Immune Deficiency

Immune Suppression Monitoring

Immune Thrombocytopenia (ITP)

What Is Immune Thrombocytopenia (ITP)? Immune thrombocytopenia (ITP) is an autoimmune condition in which your immune system mistakenly destroys platelets — the blood cells that help your blood clot and stop bleeding. This leads to a lower-than-normal platelet count, which can cause easy bruising, prolonged bleeding, and sometimes spontaneous bleeding into the skin or other tissues. ITP was previously called idiopathic thrombocytopenic purpura, but the name changed once it became clear that the cause is immune-mediated rather than unknown. "Purpura" refers to the purple-colored bruises or spots on the skin that can appear when platelet counts are low. Most people now simply say "immune thrombocytopenia" or "ITP." ITP can affect people of all ages. In children, it often starts suddenly after a viral infection and usually resolves on its own within weeks or months. In adults, it tends to be more chronic, lasting six months or longer, and may require ongoing monitoring and treatment. In short: in children, ITP usually gets better; in adults, it is more likely to be long-term.

Immunodeficiency

Immunoglobulin A (IgA) Deficiency

Here’s a clear, medically accurate, and patient-friendly overview of the health condition Immunoglobulin A (IgA) Deficiency: What Is Immunoglobulin A (IgA) Deficiency? Immunoglobulin A (IgA) Deficiency is a condition in which the body produces little or no IgA, a type of antibody that plays a crucial role in protecting mucosal surfaces such as the mouth, respiratory tract, digestive system, and genitourinary tract. IgA is also present in fluids like saliva, tears, and breast milk. It is the most common primary immunodeficiency, especially in people of European descent, and is often diagnosed during childhood or early adulthood. Why Is IgA Important? IgA helps guard against bacteria, viruses, and toxins that enter the body through mucous membranes. Without enough IgA, the immune system may have a harder time defending these surfaces, making individuals more prone to infections and, in some cases, autoimmune issues. Causes of IgA Deficiency Most cases are genetic, meaning the condition is inherited.

Inclusion Body Myositis

Inclusion Body Myositis (IBM) is a complex and progressive muscle disorder, classified as an inflammatory myopathy, characterized by a combination of inflammation and degenerative changes in muscle tissue. It is distinct among myopathies for its insidious onset and gradual progression, typically affecting individuals over the age of 50, with a higher prevalence in males. IBM's hallmark symptoms include asymmetric muscle weakness and atrophy, predominantly impacting the quadriceps, wrist, and finger flexors, leading to significant disability over time. Unlike other forms of myositis, IBM is often resistant to standard immunosuppressive therapies, posing a challenge in management and treatment. Pathologically, IBM exhibits unique features, including the presence of rimmed vacuoles and inclusion bodies in muscle fibers, indicative of both inflammatory and degenerative processes. The etiology of IBM remains largely unknown, though it is believed to involve a complex interplay of genetic predisposition and environmental factors, potentially triggering autoimmune responses.

Infection (Acute)

Acute infections are sudden-onset illnesses caused by pathogenic microorganisms including bacteria, viruses, fungi, or parasites that invade the body and multiply, triggering an immediate immune response. Common acute infections include respiratory infections (colds, flu, COVID-19, pneumonia, bronchitis), gastrointestinal infections (food poisoning, viral gastroenteritis, bacterial diarrhea), urinary tract infections, skin infections (cellulitis, abscesses, infected wounds), and throat infections (strep throat, tonsillitis). Symptoms vary depending on the type and location of infection but typically include fever, chills, fatigue, body aches, and localized symptoms such as cough, sore throat, abdominal pain, painful urination, or skin redness and warmth. The immune system responds rapidly to acute infections by producing white blood cells and antibodies to fight the invading pathogens, often causing temporary inflammation and elevated infection markers in blood tests.

Infectious Mononucleosis

Infectious Mononucleosis, often referred to as "mono" or the "kissing disease," is a contagious illness primarily caused by the Epstein-Barr Virus (EBV). This infection is widespread and known for its hallmark symptoms of fatigue, sore throat, fever, swollen lymph nodes, and at times, an enlarged spleen. Mono most commonly affects teenagers and young adults, though it can occur at any age. The virus is transmitted through saliva, which is why it earned the nickname "kissing disease," but it can also spread through coughing, sneezing, or sharing utensils with someone who is infected. Upon infection, the symptoms of mono may take 4 to 6 weeks to appear, and the severity and duration of these symptoms can vary greatly from one person to another. Some individuals may experience mild symptoms for only a few weeks, while others may have more severe symptoms that last for months. Fatigue can be particularly persistent, making it hard for those affected to keep up with their usual daily activities.

Infertility (Female)

Female infertility is defined as the inability to achieve a clinical pregnancy after 12 months of regular unprotected sexual intercourse in women under 35, or after 6 months in women 35 and older. It is one of the most common reproductive health conditions globally, affecting approximately 1 in 6 couples — and in roughly 40–50% of cases where a couple cannot conceive, a female factor is identified as the primary or contributing cause. Infertility is not a single disease but a clinical outcome with many possible underlying causes — spanning ovulatory dysfunction, structural abnormalities of the reproductive tract, endocrine disorders, immunological factors, and age-related decline in egg quality and ovarian reserve. In approximately 10–15% of cases, no identifiable cause is found despite thorough investigation — a category termed unexplained infertility. Understanding the cause is the essential first step in treatment.

Infertility (Male)

Male infertility is defined as the inability to achieve a clinical pregnancy after 12 months of regular unprotected sexual intercourse, where a male factor is identified as the primary or contributing cause. It is a major component of reproductive health, contributing to approximately 40–50% of infertility cases in couples — either as an isolated factor or in combination with female factors. Male infertility is not a single condition but a clinical outcome with multiple underlying causes. These include abnormalities in sperm production, function, or transport, as well as hormonal imbalances, genetic conditions, structural abnormalities, and environmental or lifestyle factors. In a subset of men (approximately 10–15%), no clear cause is identified despite comprehensive evaluation — termed unexplained male infertility. A structured diagnostic approach — centered on semen analysis, hormonal testing, and targeted imaging or genetic evaluation — allows most causes to be identified and significantly improves the likelihood of successful treatment.

Inflammation

Inflammation is the body's natural immune response to injury, infection, or irritation, characterized by redness, warmth, swelling, pain, and sometimes loss of function in the affected area. Acute inflammation typically develops rapidly and resolves within days to weeks once the triggering cause is removed, such as inflammation from a sprained ankle, surgical incision, or short-term infection. Chronic inflammation persists for months or years and can result from ongoing conditions like rheumatoid arthritis, inflammatory bowel disease (Crohn's disease or ulcerative colitis), psoriasis, or autoimmune disorders where the immune system mistakenly attacks healthy tissue. Systemic inflammation affects the entire body rather than a localized area and can be triggered by severe trauma, major surgery, burns, pancreatitis, or systemic inflammatory response syndrome (SIRS). Common symptoms of significant inflammation include fever, fatigue, body aches, loss of appetite, and elevated inflammatory markers in blood tests such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).

Inflammatory Bowel Disease (IBD)

Inflammatory Bowel Disease (IBD) is a term primarily used to describe two chronic conditions that cause inflammation in the gastrointestinal (GI) tract: Crohn's Disease and Ulcerative Colitis. Both are characterized by an abnormal response of the body's immune system. In IBD, the immune system mistakenly attacks the GI tract, leading to inflammation. The exact cause of this immune response is not fully understood, but it is believed to involve a complex interplay of genetic, environmental, and microbial factors. Crohn's Disease can affect any part of the GI tract, from the mouth to the anus, but most commonly affects the end of the small bowel (the ileum) and the beginning of the colon. It can affect the entire thickness of the bowel wall. In contrast, Ulcerative Colitis is limited to the colon and rectum and usually only affects the innermost lining of the bowel wall. Ulcerative Colitis (UC) is a chronic condition affecting the colon and rectum, marked by inflammation and ulceration of the colon's lining.

Inflammatory Myopathies

Influenza

Insulin Resistance

Insulin Resistance: Causes, Symptoms, and Its Role in Diabetes and Metabolic Syndrome Insulin Resistance (IR) is a growing health concern worldwide, playing a major role in the development of type 2 diabetes, obesity, and metabolic syndrome. This article explains what insulin resistance is, why it happens, and how it affects your body’s metabolism and overall health. What is Insulin Resistance? Insulin is a hormone produced by the beta cells of the pancreas, responsible for regulating blood sugar (glucose) levels. After eating, the pancreas secretes insulin to help move glucose from the bloodstream into the body’s cells, where it is used for energy production. Insulin resistance occurs when the body’s cells—especially muscle cells and fat (adipose) cells—become less responsive to insulin. This condition blocks or reduces the ability of cells to absorb glucose efficiently, leading to elevated blood sugar levels and forcing the pancreas to produce even more insulin to compensate.

Interstitial Cystitis

Interstitial cystitis (IC), also called bladder pain syndrome (BPS), is a chronic condition characterised by persistent bladder pain or discomfort, urinary urgency, and frequency in the absence of a confirmed bacterial infection. Although the exact cause is not fully understood, several mechanisms have been identified and guide current treatments. IC/BPS primarily affects women but can occur in anyone. Symptoms range from mild to severely debilitating and significantly impact quality of life. It is a diagnosis of exclusion — other causes of bladder symptoms must be ruled out first. Even though test results may appear normal, the pain and urinary symptoms are real and can be very disruptive. Symptoms Symptoms vary considerably between individuals and often come in flares, with good days and bad days. They can worsen around menstruation, after certain foods or drinks, during stress, or following sexual activity.

Interstitial Lung Disease

Interstitial Nephritis

Interstitial nephritis is inflammation of the kidney tubules and the supporting tissue surrounding them (the interstitium) — the tiny filters and structural framework that allow the kidneys to function. This inflammation impairs the kidneys' ability to filter waste and regulate fluid and electrolytes. Acute interstitial nephritis (AIN) develops over days to weeks, while chronic interstitial nephritis (CIN) progresses slowly over months to years. Drug-induced AIN is the most common form and accounts for a significant proportion of unexplained acute kidney injury. Types Acute interstitial nephritis (AIN): Develops over days to weeks, most commonly as an immune reaction to a medication. Kidney function can decline rapidly but is often reversible if the cause is identified and removed promptly — the sooner, the better. Chronic interstitial nephritis (CIN): Develops gradually, often without obvious symptoms until kidney function is significantly reduced. Because CIN progresses silently, it is often only detected through blood or urine tests.

Intestinal Permeability

Intestinal Yeast Overgrowth

Intrahepatic cholestasis of pregnancy (ICP)

Intrahepatic Cholestasis of Pregnancy (ICP), also known as obstetric cholestasis, is a liver disorder that can occur during pregnancy. This condition affects the normal flow of bile, the digestive fluid produced by the liver, causing bile acids to build up in the liver and eventually enter the bloodstream. This buildup can lead to a variety of symptoms, most notably itching, particularly on the hands and feet, which can be more severe at night and can significantly impact a pregnant woman's quality of life. Understanding ICP is crucial for expecting mothers and their families, as it not only affects maternal comfort but can also have implications for fetal well-being. ICP typically presents in the second or third trimester of pregnancy and is characterized by its most common symptom: intense itching without a rash. Other possible symptoms include jaundice (a yellowing of the skin and eyes), dark urine, light-colored stools, and fatigue. The exact cause of ICP is not fully understood, but it is believed to involve genetic, hormonal, and environmental factors.

Iron Deficiency (without anemia)

Key Takeaways Iron deficiency without anemia is the earliest stage of iron deficiency, where iron stores are low but hemoglobin remains normal Ferritin is the most important marker — low levels indicate depleted iron stores even if CBC is normal Common symptoms include fatigue, brain fog, reduced endurance, hair loss, and restless legs Most cases are caused by low intake, poor absorption, increased demand, or chronic blood loss The condition is very common, especially in women of childbearing age, athletes, and individuals with chronic disease Without treatment, it can progress to iron deficiency anemia What Is Iron Deficiency Without Anemia? Iron deficiency without anemia, also called non-anemic iron deficiency or iron depletion, is a condition where the body's iron stores are depleted but hemoglobin levels remain within the normal range. This represents the earliest stage of iron deficiency, occurring before red blood cell production becomes significantly impaired.

Iron Overload

Iron-Deficiency Anemia

Deficiency anemia is a widespread health issue affecting millions globally, significantly diminishing quality of life through its extensive symptoms. This type of deficiency anemia results from the body's lack of enough iron to manufacture hemoglobin, the crucial protein in red blood cells essential for oxygen transportation and its ability to carry oxygen. As a result, deficiency anemia can lead to symptoms such as fatigue, weakness, and shortness of breath, drastically impacting daily functions and overall well-being. The prevalence of deficiency anemia underscores the importance of addressing this health concern, as deficiency anemia can severely affect an individual's capacity to perform daily tasks and their ability to efficiently carry oxygen throughout the body. Recognizing and treating deficiency anemia early is vital to improving life quality, as untreated deficiency anemia can lead to severe complications.

Irritable Bowel Syndrome (IBS)

Irritable Bowel Syndrome (IBS) is a common disorder affecting the large intestine, characterized by a range of symptoms including abdominal pain, bloating, gas, and altered bowel habits like constipation, diarrhea, or a mix of both. Its exact cause remains unclear, but factors like muscle contractions in the intestine, nervous system abnormalities, inflammation in the intestines, severe infections, or changes in gut bacteria are thought to play a role. IBS is a chronic condition, but many people manage symptoms through diet, lifestyle changes, and stress management. The diagnosis of IBS typically involves ruling out other conditions, as there's no definitive test for it. Treatment focuses on symptom relief and can include dietary adjustments, such as increasing fiber intake or eliminating trigger foods, and medications to control muscle spasms, diarrhea, or constipation. Psychological therapies like cognitive-behavioral therapy or counseling can also be beneficial, as stress can worsen IBS symptoms.

Ischemic Colitis

Jaundice

Jaundice: Causes, Symptoms, and Treatment Jaundice is a condition characterized by a yellowing of the skin, eyes, and mucous membranes due to elevated levels of bilirubin in the blood. It is not a disease itself but rather a symptom of underlying liver, gallbladder, or blood-related conditions. What Causes Jaundice? Jaundice occurs when there is an imbalance in bilirubin metabolism. Bilirubin is a yellow pigment formed during the breakdown of red blood cells. It is processed by the liver and excreted in bile. When this process is disrupted, bilirubin accumulates in the body, leading to jaundice. The primary causes of jaundice include: Liver Diseases Hepatitis (viral, alcoholic, autoimmune) – Inflammation of the liver impairs bilirubin processing. Cirrhosis – Scarring of the liver affects its ability to remove bilirubin. Liver Cancer – Tumors may obstruct bile flow. Bile Duct Obstruction Gallstones – Blockage of the bile duct prevents bilirubin from being excreted. Pancreatic or Biliary Tract Tumors – These can compress bile ducts, leading to jaundice.

Juvenile idiopathic arthritis (JIA)

WHAT IS JUVENILE IDIOPATHIC ARTHRITIS (JIA)? Juvenile idiopathic arthritis (JIA) is the most common type of chronic arthritis in children and adolescents. It causes persistent joint inflammation (swelling, pain, and stiffness) that begins before age 16 and lasts at least six weeks. The term "idiopathic" means the exact cause is unknown, though it involves the immune system mistakenly attacking healthy joint tissues. JIA is not a single disease but rather a group of related conditions with different subtypes, each having distinct characteristics, symptoms, and treatment approaches. While JIA shares some features with adult rheumatoid arthritis, it is a separate condition with unique patterns and outcomes.

Keshan disease (KD)

Keshan Disease (KD): Causes, Symptoms, and Prevention Keshan disease (KD) is a rare but serious condition that primarily affects the heart. It is named after the Keshan County in China, where the disease was first discovered in the 1930s. KD is characterized by cardiomyopathy (damage to the heart muscle), which can lead to heart failure and other life-threatening complications. The disease is most commonly associated with a selenium deficiency, an essential trace mineral that plays a crucial role in many biological processes, including protecting cells from oxidative stress. What Causes Keshan Disease? The main cause of Keshan disease is a deficiency in selenium, a vital antioxidant that helps prevent cellular damage and supports proper heart function. Selenium is found naturally in soil and foods, but in certain regions, such as parts of China, the soil is extremely low in selenium, which affects the local food supply. People living in these areas are more likely to develop selenium deficiency, putting them at risk for Keshan disease.

Kidney Disease (Acute & Chronic)

Kidney disease refers to conditions in which the kidneys lose their ability to effectively filter waste products, regulate fluids and electrolytes, and maintain overall metabolic balance. Kidney disease can be acute, developing suddenly over hours to days, or chronic, progressing slowly over months to years. Both forms can significantly impact overall health and often require careful monitoring using blood and urine biomarkers. This page explains the differences between acute kidney injury (AKI) and chronic kidney disease (CKD), common causes and symptoms, and how laboratory tests—such as the BUN/Creatinine ratio, creatinine, and eGFR—are used to assess kidney function. What Do the Kidneys Do? The kidneys are two fist-sized organs located on either side of the spine below the rib cage.

Kidney Failure

Kidney Failure: Understanding Symptoms, Causes, and Treatment Kidney failure, or end-stage kidney disease (ESKD), is a serious condition where the kidneys lose their ability to effectively filter waste and excess fluids from the blood. This can occur suddenly (acute kidney failure) or progress gradually over time (chronic kidney disease). Symptoms of Kidney Failure Kidney failure often develops silently, with noticeable symptoms typically appearing in advanced stages. Common signs include: Fatigue and weakness Decreased urine output or changes in urination patterns Swelling in legs, ankles, or feet (edema) Shortness of breath Nausea and vomiting Loss of appetite Sleep disturbances Difficulty concentrating Itchy skin Muscle cramps In severe cases, additional symptoms may include: Uncontrolled high blood pressure Chest pain due to fluid accumulation around the heart Confusion or decreased mental sharpness What Causes Kidney Failure?

Kidney Infection (Pyelonephritis)

Kidney Infection (Pyelonephritis): Symptoms & Treatment A kidney infection, medically known as pyelonephritis, is a serious type of urinary tract infection (UTI) that occurs when bacteria travel from the bladder or urethra into one or both kidneys. If left untreated, a kidney infection can lead to permanent kidney damage or the bacteria can spread into the bloodstream, becoming life-threatening. What Causes a Kidney Infection? Most kidney infections are caused by E. coli, a common type of bacteria that normally lives in the intestines. The infection usually begins as a bladder infection (cystitis) and moves up through the ureters to the kidneys. Risk factors include: Having a history of frequent UTIs Being female (shorter urethra makes it easier for bacteria to travel) Pregnancy Kidney stones Diabetes Weakened immune system Structural problems in the urinary tract Use of a urinary catheter Symptoms of a Kidney Infection Symptoms of pyelonephritis often develop quickly and may include: Common symptoms: Fever and chills Pain in the lower back, side, or groin Frequent and painful

Kidney Stones (Nephrolithiasis)

Kidney stones (nephrolithiasis) are hard mineral and salt deposits that form inside the kidneys when there is not enough fluid in the urine to keep minerals dissolved. They can be as small as a grain of sand or, rarely, as large as a golf ball — though most are much smaller. Small stones often pass on their own; larger stones may need procedures to break them up or remove them. Kidney stones affect roughly 1 in 10 people over a lifetime and have a high recurrence rate without preventive measures. Types of kidney stones Calcium oxalate stones — the most common type, accounting for around 80% of cases. They form when calcium combines with oxalate in the urine, often in people with low fluid intake, high sodium diets, or certain metabolic conditions. You do not usually need to avoid high-oxalate foods entirely, but pairing them with dietary calcium and staying well hydrated can reduce risk. Calcium phosphate stones — less common.

Kienbock's Disease

Kienbock's Disease: A Comprehensive Overview Kienbock's disease is a rare bone disorder affecting the lunate, one of the eight small bones in the wrist. It is characterized by avascular necrosis (bone tissue death) due to interrupted blood supply, primarily affecting men aged 20-40 and rarely occurring in both wrists. Etiology and Risk Factors: Trauma to the wrist Uneven forearm bone lengths (shorter ulna compared to radius) Irregular lunate bone shape Medical conditions compromising blood supply Disease Progression: Initial blood supply loss with minor symptoms Lunate bone hardening Bone fragmentation and partial collapse Complete bone collapse affecting surrounding structures Clinical Manifestations: Wrist pain and tenderness Limited movement Stiffness and swelling Decreased grip strength Diagnostic Approach: X-ray imaging MRI scans Arthroscopic procedures Treatment Strategies: Anti-inflammatory medications Wrist immobilization (cast or splint) Surgical interventions: Bone shortening Joint fusion Nerve intervention Prognosis: While no complete cure exists, appropriate treatment can

Klinefelter Syndrome

Lactase Deficiency

Lactic acidosis

Lactic acidosis is a serious metabolic condition that occurs when lactic acid builds up in the bloodstream faster than the body can clear it, causing a high anion gap metabolic acidosis often first detected as an elevated lactate level on blood tests. It develops when lactate production increases, clearance by the liver or kidneys decreases, or both—disrupting the body’s normal acid–base balance. Lactate is produced during normal energy metabolism, especially when oxygen delivery is limited or energy demand is high. In lactic acidosis, this balance is overwhelmed, leading to accumulation of acid in the blood. Types and Mechanisms Lactic acidosis is commonly classified in clinical practice into two main types: Type A (hypoxic): Caused by inadequate oxygen delivery to tissues, leading to anaerobic metabolism and excess lactate production. This is the most common form and occurs in conditions such as sepsis, shock, severe anemia, or cardiac arrest.

Lactose Intolerance

LADA

Leaky Gut Syndrome

Understanding Leaky Gut: Causes, Symptoms, and Effective Management Strategies Do you suspect a ‘leaky gut’ is to blame for your digestive discomfort? Look no further for clarity. Leaky gut, characterized by a weakened intestinal lining, can cause symptoms from bloating to food sensitivities. In this comprehensive guide, we’ll demystify its causes, the array of symptoms it can involve, and the most effective ways to restore your gut health. Key Takeaways Leaky gut syndrome, characterized by increased intestinal permeability, allows substances from the digestive tract to leak into the bloodstream, leading to gastrointestinal symptoms such as diarrhea and bloating. The condition is associated with a spectrum of potential causes, including poor diet, excessive alcohol use, stress, imbalances in gut microbiota, and infections, and can contribute to various autoimmune and inflammatory diseases.

Leukemia / Bone Marrow Disorders

Leukocytosis

Leukopenia

Limited cutaneous systemic sclerosis

Limited Cutaneous Systemic Sclerosis (lcSSc) – Understanding the Condition What is Limited Cutaneous Systemic Sclerosis? Limited cutaneous systemic sclerosis (lcSSc) is a subtype of systemic sclerosis (scleroderma), an autoimmune connective tissue disease that causes fibrosis (hardening) of the skin and internal organs. In lcSSc, skin thickening is typically restricted to the hands, forearms, face, and lower legs, distinguishing it from diffuse systemic sclerosis, which affects larger areas of the body. This condition was historically referred to as CREST syndrome, an acronym representing its key features: Calcinosis – Calcium deposits in the skin and tissues Raynaud’s phenomenon – Reduced blood flow causing fingers/toes to turn white or blue in cold temperatures Esophageal dysmotility – Difficulty swallowing due to reduced esophageal movement Sclerodactyly – Thickened, tight skin on the fingers Telangiectasia – Dilated blood vessels appearing as red spots on the skin Causes and Risk Factors The exact cause of lcSSc remains unknown, but it is believed to result from a dysregulated

Limited Cutaneous Systemic Sclerosis (CREST Syndrome)

Liver Disease

Liver Disease (Acute)

Acute liver disease refers to sudden, significant impairment of liver function that develops over a short period — typically days to weeks. The liver performs hundreds of vital functions including filtering toxins from the blood, producing proteins needed for clotting and immune function, and metabolising drugs and nutrients. When the liver is acutely injured or inflamed, these functions are disrupted, and the effects can range from mild and self-limiting to life-threatening. Acute liver disease is a broad category that encompasses many specific conditions. The most common forms are acute viral hepatitis, drug-induced liver injury, and alcoholic hepatitis. Most cases resolve fully with treatment or removal of the cause; a smaller proportion progress to acute liver failure, which requires urgent specialist care. Causes Acute liver disease has many possible causes. The most clinically important are: Viral hepatitis Infection with hepatitis A, B, C, D, or E viruses is among the most common causes worldwide. Hepatitis A and E typically cause self-limiting acute illness.

Liver failure

Liver failure is a serious condition that occurs when the liver loses its ability to carry out vital functions such as detoxifying the blood, producing key proteins, and regulating metabolism. Abnormal blood tests—like rising bilirubin, low albumin, or prolonged clotting time—often reveal the problem before symptoms become severe. Liver failure can develop suddenly (acute liver failure) or progress gradually over time as a result of chronic liver disease (chronic liver failure). In both cases, impaired liver function leads to toxin buildup, disrupted metabolism, and abnormalities in fluid balance and blood clotting. Types and Disease Progression Liver failure is typically classified into two main forms: Acute liver failure: Develops suddenly, usually within days or weeks, in individuals without prior liver disease. It can progress rapidly and requires urgent medical attention. Chronic liver failure: Develops over months to years, often as the end stage of long-term liver disease such as cirrhosis. Symptoms and lab abnormalities worsen as liver function declines.

Lupus Nephritis

Lyme Borreliosis

Lyme Disease

If you have Lyme test results in hand, this page explains how the Western blot works, what reactive bands mean, and how to find the specific band result you are looking at. How Lyme Disease Testing Works Lyme disease testing in the US follows a two-step process recommended by the CDC: Step 1 — ELISA or EIA (screening test). A blood test that measures the overall level of antibodies against Borrelia burgdorferi, the bacterium that causes Lyme disease. If this test is negative, no further testing is typically recommended. If it is positive or equivocal, a second confirmatory test is ordered. Step 2 — Western blot (confirmatory test). This test separates Borrelia burgdorferi proteins by molecular weight and identifies which specific proteins your immune system has produced antibodies against. Results are reported band by band, with each band corresponding to a specific protein. The Western blot is not ordered or interpretable in isolation — it is a confirmatory test, meaningful only in the context of a positive or equivocal first-tier ELISA. IgG vs.

Lymphadenopathy

Lymphadenopathy: Understanding Swollen Lymph Nodes Lymphadenopathy refers to the swelling or enlargement of lymph nodes—small, bean-shaped glands that play a crucial role in the immune system. These nodes are found throughout the body, including the neck, armpits, groin, and abdomen. This condition is relatively common and is typically caused by infections, although other factors can contribute. Common Causes of Lymphadenopathy Infections Viral infections, such as the common cold, flu, or strep throat, are the most frequent causes. Autoimmune Diseases Conditions like lupus or rheumatoid arthritis can trigger lymph node swelling. Malignancies Although rare, cancers such as lymphoma or leukemia may present with swollen lymph nodes. Medications Certain drugs may cause lymph node enlargement as a side effect.

Lymphocytopenia

Lymphocytosis

Lymphoma

Lymphopenia

Macrocytic Anemia

Malnutrition

Maple syrup urine disease (MSUD)

Maple Syrup Urine Disease (MSUD): Causes, Symptoms, Diagnosis, and Treatment Maple Syrup Urine Disease (MSUD) is a rare genetic metabolic disorder that affects the body's ability to break down certain amino acids: leucine, isoleucine, and valine. This leads to a toxic buildup of these amino acids and their byproducts in the blood, which can cause severe neurological damage and life-threatening complications if left untreated. The condition gets its name from the distinct sweet, maple syrup-like odor in the urine and sweat of affected individuals. Causes and Genetics MSUD is an autosomal recessive disorder, meaning a child must inherit two defective copies of the BCKDHA, BCKDHB, or DBT gene—one from each parent. These genes encode for the branched-chain ketoacid dehydrogenase (BCKD) complex, which is responsible for breaking down branched-chain amino acids (BCAAs). When this enzyme complex is deficient or malfunctioning, these amino acids accumulate to toxic levels.

Mast Cell Activation Syndrome (MCAS)

Key Takeaways Mast Cell Activation Syndrome (MCAS) is a condition in which mast cells release excessive inflammatory chemicals, such as histamine, tryptase, prostaglandins, and leukotrienes. These mediators can cause symptoms affecting multiple body systems, including the skin, digestive tract, respiratory system, cardiovascular system, and nervous system. Common symptoms include flushing, hives, abdominal pain, diarrhea, wheezing, rapid heart rate, fatigue, and brain fog. Diagnosis typically requires three components: compatible symptoms in multiple organ systems, laboratory evidence of mast cell mediator release, and improvement with mast cell–targeted treatment. Treatment focuses on trigger avoidance, antihistamines, mast cell stabilizers, and other medications that reduce mediator release or block their effects. What Is Mast Cell Activation Syndrome? Mast Cell Activation Syndrome (MCAS) is a disorder in which mast cells become overactive and release inflammatory chemicals too frequently or in excessive amounts.

Mastocytosis

Megaloblastic Anemia

Meningitis

Menopause

Menopause is the permanent cessation of menstrual periods, defined as 12 consecutive months without a period in the absence of other causes. It marks the end of a woman's reproductive years and is a natural biological transition, not a disease — but the hormonal changes it brings have far-reaching effects on nearly every organ system, and the years surrounding it are associated with significant health risks that deserve proactive attention. Menopause occurs because the ovaries exhaust their supply of follicles — the structures that produce eggs and hormones. As follicle reserves deplete, estradiol production falls and follicle-stimulating hormone (FSH) rises. The average age of natural menopause in Western populations is 51, with most women transitioning between ages 45 and 55. Menopause occurring before age 40 is classified as premature ovarian insufficiency (POI) and carries specific clinical implications.

Menstrual Irregularity

Metabolic Acidosis

Metabolic acidosis is a common acid–base disorder that occurs when there is either too much acid in the body or too little bicarbonate, causing blood pH to fall. It is often first detected on routine blood tests showing low bicarbonate and changes in the anion gap, sometimes before symptoms become severe. This condition develops when acid production increases, acid excretion by the kidneys is impaired, or bicarbonate is lost from the body. The result is a disruption in the body’s normal acid–base balance, which is essential for proper cellular function. Types and Mechanisms Metabolic acidosis is typically classified based on the anion gap, a key lab calculation used to identify the underlying cause: High anion gap metabolic acidosis: Caused by the accumulation of unmeasured acids in the blood.

Metabolic alkalosis

Metabolic disorders

Metabolic syndrome

Metabolic Syndrome: Causes, Risk Factors, Diagnosis, and Management What is Metabolic Syndrome? Metabolic syndrome is a cluster of conditions that together increase the risk of cardiovascular disease, type 2 diabetes, and other serious health complications. It is characterized by a combination of high blood pressure, elevated blood sugar levels, excess abdominal fat, and abnormal cholesterol or triglyceride levels. The presence of three or more of these factors is typically used to diagnose metabolic syndrome. Causes and Risk Factors Metabolic syndrome is primarily driven by insulin resistance, a condition in which the body's cells do not respond effectively to insulin. This leads to elevated blood sugar levels and a cascade of metabolic imbalances. Key risk factors include: Obesity – Particularly central (abdominal) obesity, often measured by waist circumference. Sedentary Lifestyle – Lack of physical activity contributes to insulin resistance and weight gain.

Methylmalonic acidemia (MMA)

Methylmalonic Acidemia (MMA): A Comprehensive Guide What is Methylmalonic Acidemia (MMA)? Methylmalonic acidemia (MMA) is a rare genetic metabolic disorder that impairs the body’s ability to break down certain proteins and fats. This condition is caused by mutations in genes responsible for processing methylmalonyl-CoA, leading to the accumulation of toxic substances, including methylmalonic acid, in the blood and tissues. MMA can result in serious health issues, especially if not diagnosed and managed early. It is one of the most well-known organic acidemias, a group of disorders that affect how the body processes specific amino acids and lipids. What Causes MMA? MMA is caused by genetic mutations in the following pathways: Deficiency of Methylmalonyl-CoA Mutase (MUT): The enzyme responsible for converting methylmalonyl-CoA into succinyl-CoA is defective or absent. Vitamin B12 (Cobalamin) Processing Defects: MMA can also result from errors in the body’s ability to process vitamin B12, which is essential for methylmalonyl-CoA mutase function.

Microcytic Anemia

Mild Cognitive Impairment (MCI)

Mixed connective tissue disease (MCTD)

Mixed Connective Tissue Disease (MCTD) is an autoimmune disorder characterized by features commonly seen in three other connective tissue diseases: systemic lupus erythematosus, scleroderma, and polymyositis. MCTD is thus considered an overlap syndrome. Patients with MCTD may exhibit a variety of symptoms, including joint pain, muscle weakness, Raynaud's phenomenon (a condition where fingers and toes turn white or blue and feel cold in response to cold temperatures or stress), and problems with internal organs such as the lungs and kidneys. A distinctive marker for MCTD is the presence of high levels of anti-U1 ribonucleoprotein (anti-U1 RNP) antibodies in the blood. The course of MCTD varies among individuals; some experience only mild symptoms, while others may have a more severe progression requiring active management. Treatment is tailored to the individual's symptoms and may include medications that suppress the immune system, such as corticosteroids and immunosuppressants.

Mold Allergy

Mold exposure

Monoclonal Gammopathy of Undetermined Significance (MGUS)

What Is MGUS? Monoclonal Gammopathy of Undetermined Significance (MGUS) is a benign condition in which an abnormal protein—called a monoclonal protein or M protein—is found in the blood. Key facts about MGUS: Not cancer — it is a benign condition Affects 3–4% of adults over age 50 Usually causes no symptoms Requires monitoring but often no treatment Risk of progression to cancer is low (~1% per year) How MGUS Is Diagnosed MGUS is often discovered during routine blood tests or while evaluating other conditions. Diagnosis typically includes: Protein electrophoresis (SPEP): Detects abnormal protein bands Immunofixation: Identifies the specific type of protein M protein level: Usually less than 3 g/dL in MGUS Bone marrow evaluation: Less than 10% plasma cells No organ damage: No bone lesions, kidney dysfunction, anemia, or elevated calcium MGUS vs.

Multiple Endocrine Neoplasia type 2 (MEN2)

Multiple Myeloma

Multiple Myeloma is a complex and aggressive hematological malignancy characterized by the uncontrolled proliferation of plasma cells in the bone marrow. Plasma cells, a type of white blood cell, are crucial for producing antibodies (immunoglobulins) that fight infection. In Multiple Myeloma, these cells become cancerous (myeloma cells) and produce large amounts of a single type of abnormal antibody known as a monoclonal protein, or M protein, which can be detected in blood or urine. These malignant plasma cells crowd out healthy blood cells and produce substances that cause bone destruction, leading to pain and fractures. The pathophysiology of Multiple Myeloma involves genetic and epigenetic alterations, leading to the disruption of normal plasma cell growth and death. Common genetic aberrations include chromosomal translocations and deletions, particularly involving chromosome 14. These changes result in the overexpression of oncogenes or the loss of tumor suppressor genes, promoting myeloma cell survival and proliferation.

Multiple sclerosis (MS)

Multiple Sclerosis (MS) is a chronic and often debilitating neurological condition that affects the central nervous system, which includes the brain and spinal cord. This autoimmune disease occurs when the body's immune system mistakenly attacks the protective covering of nerve fibers, known as myelin, leading to inflammation and damage. This damage disrupts the communication between the brain and the rest of the body, resulting in a wide range of symptoms that vary from person to person. Common symptoms of MS include fatigue, numbness or tingling in the limbs, muscle weakness, vision problems, and difficulties with coordination and balance. Over time, these symptoms can become more severe, leading to mobility issues and other significant health challenges. While the exact cause of MS is unknown, it is believed to involve a combination of genetic and environmental factors. There is currently no cure for multiple sclerosis, but there are various treatment options available that can help manage symptoms, reduce the frequency of relapses, and slow the progression of the disease.

Muscle Trauma

Muscular Dystrophy

Myasthenia Gravis

What Is Myasthenia Gravis? Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder that causes weakness in the skeletal muscles—the muscles your body uses for movement. The name comes from Latin and Greek, meaning “grave muscle weakness,” though with proper treatment, many people with MG lead normal or near-normal lives. In MG, the immune system mistakenly produces antibodies that interfere with the communication between nerves and muscles, leading to muscle fatigue and weakness that typically worsens with activity and improves with rest. What Causes It? In most cases, MG is caused by antibodies that attack acetylcholine receptors (AChR) at the neuromuscular junction—the place where nerve cells signal muscles to move. Some patients may have antibodies against other proteins involved in this process, such as: MuSK (Muscle-Specific Kinase) LRP4 (Low-Density Lipoprotein Receptor-Related Protein 4) These antibodies block or destroy the receptors needed for muscle contraction, preventing normal muscle activation. Who Can Get Myasthenia Gravis?

Mycoplasma pneumoniae Infection

Mycoplasma pneumoniae is a significant bacterial pathogen known primarily for causing atypical pneumonia, though it can also be associated with a range of other respiratory conditions and extrapulmonary manifestations. Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, or fungi. Understanding its biology, epidemiology, clinical presentation, diagnostic methods, and treatment is crucial in managing infections caused by this bacterium. Biology and Epidemiology Mycoplasma pneumoniae is unique among bacteria due to its lack of a cell wall, which makes it naturally resistant to antibiotics that target cell wall synthesis, like penicillin. This small bacterium is primarily spread through respiratory droplets, leading to outbreaks in crowded environments such as schools and military barracks. It's more prevalent in late summer and fall, but infections can occur year-round. Clinical Presentation The infection often presents as a mild respiratory illness, but can progress to more severe pneumonia.

Myelodysplastic Syndrome (MDS)

What Is Myelodysplastic Syndrome (MDS)? Myelodysplastic syndrome (MDS) is a group of blood disorders in which the bone marrow does not produce enough healthy, functional blood cells. Instead of maturing normally, blood cells develop abnormally — a process called dysplasia — and many are destroyed before they ever leave the bone marrow. The result is a shortage of one or more types of blood cells: red blood cells, white blood cells, or platelets. MDS is not a single disease but a spectrum of related conditions ranging from low-risk forms that progress slowly over many years to high-risk forms that can transform into acute myeloid leukemia (AML). The course of MDS varies widely — many people have slow-growing forms that can be monitored and managed for years. Understanding where on this spectrum a person's MDS falls is one of the most important parts of diagnosis and treatment planning. MDS is primarily a disease of older adults, with most diagnoses occurring after age 65. It is slightly more common in men than women. In most people, MDS is not passed down in families.

Myeloproliferative Disorders

Myeloproliferative Neoplasms

Myeloproliferative neoplasms (MPNs) are a group of rare blood cancers characterized by the bone marrow's overproduction of one or more types of mature blood cells—red blood cells, white blood cells, or platelets—due to acquired mutations in blood-forming stem cells. The main types of MPNs include polycythemia vera (overproduction of red blood cells), essential thrombocythemia (overproduction of platelets), primary myelofibrosis (bone marrow scarring with abnormal blood cell production), and chronic neutrophilic leukemia (overproduction of neutrophils). Many patients have no symptoms initially and are diagnosed through routine blood tests, but as the disease progresses, symptoms may include fatigue, weakness, headaches, dizziness, night sweats, itching (especially after warm baths), enlarged spleen causing abdominal fullness or pain, bleeding complications, blood clots (which can lead to stroke or heart attack), and bone pain.

Myositis

Nasopharyngeal Carcinoma

Neonatal Herpes

Neonatal herpes is a rare but potentially life-threatening infection in newborns caused by herpes simplex virus (HSV), usually transmitted during vaginal delivery if the mother has an active genital herpes infection. Although uncommon, neonatal herpes requires urgent medical attention due to the risk of severe complications, including: Skin, eye, and mouth infections Central nervous system involvement (encephalitis) Disseminated infection affecting multiple organs Symptoms in newborns may include: Skin blisters Fever or lethargy Poor feeding Irritability Seizures in severe cases The risk of transmission is highest when a mother acquires HSV late in pregnancy or has active lesions at delivery. Prevention strategies include: Screening and monitoring during pregnancy Antiviral therapy in late pregnancy for known HSV infection Cesarean delivery if active genital lesions are present Early diagnosis and treatment with intravenous antiviral therapy (e.g., acyclovir) significantly improve outcomes. While neonatal herpes is serious, it is rare, and proper prenatal care greatly reduces risk.

Neonatal Jaundice

Neonatal Lupus

Nephrotic syndrome

Nephrotic syndrome is one of the most common causes of low albumin, heavy proteinuria, and unexplained swelling—and is often first detected through routine lab testing. It is a kidney disease characterized by excessive protein loss in the urine (typically more than 3.5 grams per day). This occurs when the kidneys’ filtering units become damaged and less effective, allowing large amounts of protein to pass into the urine. Because this protein loss disrupts normal fluid balance, it leads to a recognizable set of findings: low blood albumin (hypoalbuminemia), fluid retention (edema), high cholesterol and triglycerides (hyperlipidemia), and fat in the urine (lipiduria).

Neurodegenerative Diseases

Neurodegenerative Diseases: Understanding a Complex Health Category Neurodegenerative diseases are a group of conditions that involve the progressive loss of structure and function of neurons, the specialized cells that make up the brain and nervous system. These diseases often worsen over time and can affect movement, cognition, behavior, and vital bodily functions, depending on which parts of the nervous system are involved. Because the nervous system controls so many aspects of health—from memory to muscle strength—neurodegenerative disorders can lead to profound disability, loss of independence, and, in many cases, reduced lifespan. Despite their complexity, advances in diagnostics, biomarker testing, and disease-modifying therapies are offering new hope for earlier detection and more personalized management. Common Neurodegenerative Diseases Neurodegenerative conditions vary widely in their symptoms and rate of progression. Some of the most recognized diseases in this category include: 1.

Neuroinflammatory disorders

Neuroinflammatory disorders are conditions in which the immune system triggers chronic inflammation within the brain, spinal cord, or peripheral nerves. While inflammation is a normal immune response to injury or infection, excessive or misdirected inflammation in the nervous system can damage neurons, disrupt communication between brain cells, and contribute to a wide range of neurological symptoms and diseases. Neuroinflammation is increasingly recognized as a root cause or contributing factor in many chronic neurological conditions. It can arise from autoimmune activation, chronic infections, metabolic stress, environmental toxins, or gut-brain axis dysregulation.

Neutropenia

Neutrophilia

Non-Alcoholic Fatty Liver Disease (NAFLD) / NASH

Non-Celiac Gluten Sensitivity

Non-Hodgkin Lymphoma

Non-Hodgkin Lymphoma (NHL) is a diverse group of blood cancers that originate in the lymphatic system, a vital part of the immune system responsible for defending the body against infections and diseases. Unlike Hodgkin lymphoma, NHL consists of multiple subtypes, each with distinct characteristics and behaviors. The two primary categories are B-cell lymphomas, which arise from abnormal B lymphocytes, and T-cell lymphomas, originating from T lymphocytes. B-cell lymphomas are the most common, making up the majority of NHL cases. While NHL can develop at any age, its risk increases with age, and it is more frequently diagnosed in men than women. Non-Hodgkin Lymphoma (NHL) causes the abnormal growth and accumulation of lymphocytes, a type of white blood cell, which can lead to the formation of tumors in the lymph nodes and other parts of the body, disrupting the normal function of the immune system and other organs. The symptoms of NHL can vary widely depending on the subtype and the areas affected.

Non-Thyroidal Illness Syndrome (Sick Euthyroid Syndrome)

Nonketotic hyperglycinemia (NKH)

Understanding Nonketotic Hyperglycinemia (NKH) What is Nonketotic Hyperglycinemia (NKH)? Nonketotic Hyperglycinemia (NKH), also known as glycine encephalopathy, is a rare genetic disorder that impairs the body’s ability to process glycine, an amino acid essential for protein synthesis. This disruption leads to an abnormal accumulation of glycine in various tissues and organs, particularly in the brain, resulting in severe neurological issues. Types and Severity of NKH NKH can be classified into two main forms: Classical Form Severe Subtype: More common and presents serious symptoms, often leading to significant neurological damage and life-threatening complications. Attenuated (Mild) Subtype: While still serious, this form may allow for some developmental progress, though affected children may experience delayed milestones and other neurological challenges. Variant Form: This form presents with different clinical features and may have varying severity. Symptoms and Diagnosis Symptoms of NKH typically manifest shortly after birth or within the first few months of life.

Obesity

Obstructive Sleep Apnea

Oral Herpes (Herpes Labialis)

Oral herpes (herpes labialis) is one of the most common viral infections worldwide, primarily caused by HSV-1. After initial exposure, the virus remains dormant in nerve cells and can reactivate periodically, leading to cold sores. Typical symptoms include tingling, burning, or itching around the lips followed by fluid-filled blisters that crust over and heal within 7–10 days. Many individuals never experience symptoms, despite carrying the virus. Outbreaks are often triggered by stress, illness, fatigue, sun exposure, or immune suppression. The first episode may be more severe and can include fever, swollen lymph nodes, and painful oral lesions. Oral herpes is highly contagious during active outbreaks and spreads through direct contact, such as kissing or sharing utensils. However, transmission risk is low when no sores are present. Treatment includes antiviral medications such as acyclovir or valacyclovir, which can shorten outbreak duration and reduce severity. Most cases are mild and do not require ongoing treatment.

Osteoarthritis

Osteopenia

Osteoporosis

Overview Osteoporosis is a skeletal disease characterized by reduced bone mineral density and deterioration of bone microarchitecture, leading to increased bone fragility and fracture risk. The word itself means "porous bone" — and under a microscope, osteoporotic bone shows the enlarged holes and weakened struts that make fractures more likely even from minor falls or, in severe cases, everyday activity. Osteoporosis is often called a silent disease because bone loss occurs without pain or symptoms. Most people are unaware they have it until a fracture occurs — commonly of the hip, spine, or wrist. It is one of the most common chronic conditions worldwide, affecting an estimated 200 million people globally, with postmenopausal women at highest risk. The condition is detected and monitored through bone density testing (DEXA scan) and supported by a panel of blood and urine markers that assess bone turnover, calcium metabolism, vitamin D status, and hormonal balance. How Bone Density Works Bone is living tissue that undergoes continuous remodeling throughout life.

Overlap Syndromes (Polymyositis/Scleroderma)

Overlapping Autoimmune Diseases

Overlapping Autoimmune Diseases (Overlap Syndromes): What It Means Overlapping autoimmune diseases occur when the immune system causes inflammation and tissue damage in a way that does not fit neatly into a single diagnosis. Instead, a person may meet criteria for multiple autoimmune diseases, or they may have a combination of symptoms and antibodies that strongly suggest more than one condition. What overlap syndromes are (in simple terms) An overlap syndrome means: Your immune system is acting in an autoimmune way More than one autoimmune “pattern” is present Symptoms may involve multiple body systems at once The condition may shift or become clearer over time Common Types of Autoimmune Overlap Overlap syndromes most often involve connective tissue diseases, including: Lupus overlap May include features of lupus plus another autoimmune condition, such as inflammatory arthritis, Sjögren’s, or myositis. Rheumatoid arthritis overlap May involve joint swelling and pain typical of rheumatoid arthritis plus symptoms of lupus or Sjögren’s.

Ovulatory Dysfunction

Paget's Disease of Bone

Paraganglioma

Paraneoplastic Neurologic Syndromes (PNS)

Paraneoplastic neurological syndromes (PNS) represent a group of rare, diverse conditions that affect the nervous system and are associated with cancer. These syndromes are not caused directly by the tumor itself but are thought to result from the body's immune response to the cancer. When the immune system attacks the cancer cells, it can mistakenly target healthy cells in the nervous system, leading to a variety of neurological symptoms. PNS can affect any part of the nervous system, including the brain, spinal cord, nerves, and muscles. The symptoms and severity of PNS vary widely among patients, depending on which part of the nervous system is affected. Common symptoms include difficulty with coordination, loss of muscle control, sensory changes, and cognitive dysfunction. Paraneoplastic opsoclonus/myoclonus syndrome and paraneoplastic cerebellar degeneration (PCD) are two specific types of PNS. Paraneoplastic opsoclonus/myoclonus syndrome is characterized by rapid, uncontrollable eye movements (opsoclonus) and brief, involuntary muscle jerks (myoclonus).

Parasitic Infections

Parasitic infections are caused by organisms that live on or within a host, deriving nutrients at the host’s expense. These organisms—classified broadly as protozoa, helminths (worms), and ectoparasites—can infect various parts of the body, including the gastrointestinal tract, blood, skin, and organs. Parasitic infections are more common in regions with limited sanitation and clean water access, but they can occur globally due to travel, food exposure, and environmental contact. Common parasitic infections include giardiasis, amoebiasis, malaria, toxoplasmosis, and intestinal worm infections such as roundworms, hookworms, and tapeworms. Transmission occurs through contaminated food or water, insect vectors (such as mosquitoes), soil exposure, or person-to-person contact, depending on the parasite. Symptoms vary widely based on the type of parasite, infection site, and host immune response. Gastrointestinal parasites may cause diarrhea, abdominal pain, bloating, nausea, and nutrient malabsorption.

PBC/Autoimmune Hepatitis Overlap Syndrome

Pericarditis

What Is Pericarditis? Pericarditis is inflammation of the pericardium, the thin, two-layered, fluid-filled sac that surrounds and protects the heart. Normally, a small amount of lubricating fluid sits between these layers, allowing the heart to move smoothly as it beats. When the pericardium becomes inflamed, the layers can rub against each other, causing chest pain and irritation around the heart. Types of Pericarditis Pericarditis is classified based on how long symptoms last: Acute pericarditis: sudden onset, lasting less than 3 weeks Subacute pericarditis: develops gradually, lasting 3 weeks to 3 months Chronic pericarditis: persists longer than 3 months Recurrent pericarditis: symptoms return after initial recovery It can affect people of any age but is most common in adults aged 20–50, with men affected more frequently than women.

Perimenopause

Perimenopause is the transitional phase leading up to menopause — the period during which the ovaries gradually reduce their production of estrogen and progesterone, ovulation becomes irregular, and the hormonal architecture of the reproductive years begins to shift. It is one of the most clinically significant and underrecognized hormonal transitions in women's health. The term means literally "around menopause." Unlike menopause itself — which is a specific event defined as 12 consecutive months without a period — perimenopause is a dynamic, multi-year process. It typically begins in a woman's mid-to-late 40s, though for some women it starts as early as the late 30s. Average duration is 4–8 years, though it can last as few as 1 year or as long as 10. Perimenopause ends and menopause begins with the final menstrual period — confirmed only in retrospect, once 12 months have passed without a period. A critical point that is frequently missed: perimenopause is not pre-menopause in the sense of being symptom-free.

Peripheral Neuropathy

Pernicious Anemia

Pharyngitis

Pheochromocytoma

Pneumonia

Polyclonal / Reactive Conditions

What Is Polyclonal Hypergammaglobulinemia? Polyclonal hypergammaglobulinemia refers to an increase in multiple different types of immunoglobulins (antibodies) in the blood. Unlike monoclonal conditions (such as MGUS or multiple myeloma), where a single abnormal protein is produced, polyclonal patterns reflect normal immune system activity responding to infection, inflammation, or other triggers. Key characteristics: Benign finding in most cases Multiple protein types elevated (not just one) Reflects active immune response Not associated with blood cancers Often improves when the underlying condition is treated Important: Polyclonal patterns are fundamentally different from monoclonal patterns and do not indicate plasma cell disorders like myeloma. Polyclonal vs.

Polycystic Kidney Disease

Polycystic ovary syndrome (PCOS)

Polycystic Ovary Syndrome (PCOS) Polycystic Ovary Syndrome (PCOS) is a common hormonal disorder affecting approximately 1 in 10 women of reproductive age. It is a complex condition with a wide range of symptoms that vary from person to person, primarily impacting reproductive health but also influencing metabolism and overall well-being. PCOS is characterized by hormonal imbalances that disrupt ovulation, often leading to irregular menstrual cycles, infertility, and the development of multiple small cysts on the ovaries, which may be detected via ultrasound. These hormonal disruptions are frequently associated with elevated androgen (male hormone) levels, contributing to symptoms such as acne, excessive hair growth (hirsutism), and scalp hair thinning. Additionally, PCOS is linked to metabolic concerns, including insulin resistance, an increased risk of type 2 diabetes, high cholesterol, hypertension, and heart disease. Diagnosis of PCOS Diagnosing PCOS can be challenging due to its diverse presentation and the absence of a single definitive test.

Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm in which the bone marrow produces too many red blood cells, and often excess white blood cells and platelets as well. It is caused by an acquired genetic mutation — most commonly JAK2 V617F, present in approximately 95% of cases — that drives uncontrolled blood cell production. PV is not inherited and is not a cancer in the conventional sense, though it carries a risk of progression to more serious conditions if untreated. The excess red blood cells thicken the blood, slowing circulation and increasing the risk of blood clots, which is the primary source of serious complications including stroke, deep vein thrombosis, and pulmonary embolism.

Polymyalgia rheumatica

Polymyositis

Post-Splenectomy State

Post-Surgical/Trauma Stress

Post-surgical and post-trauma stress refers to the body's physiological response to major physical injury or invasive surgical procedures, characterized by a coordinated cascade of metabolic, hormonal, and immune system changes aimed at promoting healing and survival. This stress response, also known as the surgical stress response or trauma response, is a normal and expected reaction that begins immediately after injury or surgery and typically lasts for several days to weeks depending on the severity of the insult. The body responds to surgical or traumatic injury through multiple interconnected pathways including activation of the hypothalamic-pituitary-adrenal axis leading to increased cortisol release, stimulation of the sympathetic nervous system causing elevated heart rate and blood pressure, release of inflammatory cytokines and acute-phase proteins, mobilization of energy stores through increased glucose production and protein breakdown, activation of the coagulation system to prevent excessive bleeding, and stimulation of bone marrow to produce increased numbers of white

Post-Transplant Immune Reconstitution

Post-Treatment Lyme Disease Syndrome

Postpartum Thyroiditis

Prader–Willi syndrome (PWS)

Precocious Puberty

Prediabetes

Preeclampsia

Pregnancy Complications

Pregnancy complications are medical conditions that arise during pregnancy and can affect the health of the mother, the developing baby, or both, ranging from mild issues that resolve with minimal intervention to serious conditions requiring immediate medical care. These complications can occur at any stage of pregnancy—during the first trimester, second trimester, third trimester, or during labor and delivery—and may develop suddenly or progress gradually over time. Common pregnancy complications include gestational diabetes (elevated blood sugar that develops during pregnancy), preeclampsia (high blood pressure with protein in the urine, typically occurring after 20 weeks of gestation), placenta previa (placenta covering the cervix), placental abruption (premature separation of the placenta from the uterine wall), preterm labor (labor beginning before 37 weeks), hyperemesis gravidarum (severe nausea and vomiting), infections such as urinary tract infections or chorioamnionitis (infection of the amniotic fluid and membranes), HELLP syndrome (a severe variant of preeclampsia

Premature Ovarian Insufficiency (POI)

Premature ovarian insufficiency (POI) is a condition in which the ovaries stop functioning normally before the age of 40. It is characterized by the loss of regular follicular activity, resulting in low estrogen production, elevated gonadotropins, and the cessation or irregularity of menstrual periods — often accompanied by infertility and symptoms similar to menopause. POI is distinct from natural menopause in several critical ways: it occurs decades earlier than expected, it carries significant long-term health consequences that are amplified by the extended duration of estrogen deficiency, it is frequently intermittent rather than permanent in its early stages, and in approximately 5–10% of affected women, spontaneous ovulation and even pregnancy can still occur after diagnosis. POI affects approximately 1 in 100 women by age 40, 1 in 1,000 by age 30, and 1 in 10,000 by age 20.

Prerenal Azotemia

Primary Biliary Cholangitis (PBC)

Primary Biliary Cholangitis (PBC): Overview and Management Primary Biliary Cholangitis (PBC) is a chronic, progressive autoimmune liver disease that leads to the gradual destruction of small bile ducts within the liver. It primarily affects women, with a female-to-male ratio of at least 9:1. Key Features of PBC Bile Duct Damage: PBC causes inflammation and scarring of the intrahepatic bile ducts, leading to bile buildup in the liver (cholestasis). Progression: Without treatment, PBC can lead to liver fibrosis, cirrhosis, and eventually liver failure. Prevalence: PBC is a relatively rare condition, affecting approximately 1 in 3,000 to 4,000 people. Symptoms of PBC Early Stages: Many individuals are asymptomatic at the time of diagnosis, with about 60% identified before symptoms appear.

Primary Myelofibrosis

Primary myelofibrosis (PMF) is a chronic myeloproliferative neoplasm in which the bone marrow becomes progressively replaced by fibrous scar tissue, disrupting its ability to produce blood cells normally. As the marrow fails, the spleen and liver take over blood cell production — a process called extramedullary hematopoiesis — leading to significant organ enlargement and a range of debilitating symptoms. PMF is driven by acquired genetic mutations, most commonly JAK2 V617F (present in approximately 50–60% of cases), CALR mutations (approximately 25%), or MPL mutations (approximately 5–10%). Around 10% of cases carry none of these three driver mutations (triple-negative PMF).

Prolactinoma

Propionic acidemia (PA)

Propionic aciduria

Prostate Cancer

Prostatitis

Proteinuria

Pseudogout

Psoriasis

Psoriasis is a chronic skin condition characterized by the rapid growth of skin cells, leading to thick, red, scaly patches on the skin. Normally, skin cells grow and shed over a period of weeks, but in psoriasis, this process is significantly accelerated, occurring over days. This results in the accumulation of skin cells on the surface, forming the distinctive plaques. Psoriasis is thought to be an autoimmune disorder, where the immune system mistakenly attacks healthy skin cells as if they were a threat, triggering this rapid turnover. The exact cause of psoriasis is not fully understood, but it is believed to involve a combination of genetic factors and environmental triggers. Triggers can vary from person to person and might include stress, skin injury (like cuts or scrapes), certain medications, or infections. Psoriasis is not contagious, meaning it cannot be spread from person to person. Symptoms of psoriasis can vary in severity and form.

Psoriatic Arthritis

Pulmonary arterial hypertension

Pulmonary Embolism

Pulmonary Hypertension

Raynaud's Phenomenon

Raynaud's Syndrome

Reactive Arthritis

Recurrent miscarriage

Recurrent UTI

Renal Tubular Acidosis

Resistant Hypertension

Rhabdomyolysis

Rheumatoid Arthritis (RA)

What Is Rheumatoid Arthritis? Causes, Signs & Symptoms, Diagnosis, Treatment, and Prevention What Is Rheumatoid Arthritis? Rheumatoid arthritis, or RA, is an autoimmune and inflammatory disease, which means that your immune system attacks healthy cells in your body by mistake, causing inflammation (painful swelling) in the affected parts of the body. Unlike the wear-and-tear damage of osteoarthritis, rheumatoid arthritis affects the lining of your joints, causing a painful swelling that can eventually result in bone erosion and joint deformity. The inflammation associated with rheumatoid arthritis is what can damage other parts of the body as well. While new types of medications have improved treatment options dramatically, severe rheumatoid arthritis can still cause physical disabilities. Rheumatoid arthritis mainly attacks the joints, usually many joints at once. Rheumatoid arthritis commonly affects joints in the hands, wrists, and knees. In a joint with Rheumatoid arthritis, the lining of the joint becomes inflamed, causing damage to joint tissue.

Rotavirus Infection

Sarcoidosis

Understanding Sarcoidosis: Causes and Symptoms Sarcoidosis is an inflammatory disease characterized by the formation of tiny clusters of immune cells called granulomas, which can occur in various organs throughout the body. The exact cause of sarcoidosis remains unknown, but it is believed to result from an abnormal immune response to environmental or infectious agents in genetically predisposed individuals. This disease most commonly affects the lungs and lymph nodes, but it can also involve the eyes, skin, heart, liver, and other organs. Symptoms of sarcoidosis vary widely depending on the organs involved. Common symptoms include persistent dry cough, shortness of breath, chest pain, fatigue, and swollen lymph nodes. In some cases, individuals may develop skin rashes, red or painful eyes, or experience joint pain and swelling. Diagnosing Sarcoidosis: Tests and Procedures Diagnosing sarcoidosis can be challenging because its symptoms overlap with those of many other conditions.

Sarcopenia

Schistosoma

Scleroderma

What is Scleroderma? Scleroderma, also known as systemic sclerosis, is a rare autoimmune condition characterized by the hardening and tightening of the skin and connective tissues. It can also affect internal organs, blood vessels, and the digestive system. The condition can range from mild to severe, and while there is no known cure, treatment options are available to manage symptoms and slow disease progression. Scleroderma is not contagious, cancerous, or infectious. Types of Scleroderma Scleroderma is broadly categorized into two main types: Localized Scleroderma (Morphea): This type mainly affects the skin, often appearing as waxy patches or streaks. It does not generally affect internal organs. Localized scleroderma is more common in children and tends to have a less severe prognosis than systemic forms. Systemic Sclerosis (SSc): This type can affect multiple organs and systems in the body, including the lungs, heart, digestive tract, and kidneys.

Seasonal Allergies

Selective IgA Deficiency

What is Selective IgA Deficiency? Selective IgA deficiency is the most common primary immunodeficiency disorder, affecting approximately 1 in 500 people in populations of European descent. It occurs when the body produces little to no immunoglobulin A (IgA) antibodies while maintaining normal levels of other antibody types (IgG and IgM). IgA antibodies play a crucial role in protecting mucous membranes lining the respiratory and digestive tracts, so people with IgA deficiency may have increased susceptibility to infections in these areas. The condition is defined by serum IgA levels below 7 mg/dL (normal adult range is 70-400 mg/dL) with normal IgG and IgM levels and normal immune cell function. Most people with selective IgA deficiency have levels below 5 mg/dL or completely undetectable IgA. Symptoms and Clinical Presentation Many people with selective IgA deficiency have no symptoms at all and are only diagnosed incidentally during blood work for other reasons.

Selenosis

Sepsis

Sepsis is a life-threatening medical emergency that occurs when the body's response to an infection becomes dysregulated, causing widespread inflammation that can lead to tissue damage, organ failure, and death if not promptly treated. While sepsis most commonly develops from bacterial infections such as pneumonia, urinary tract infections, abdominal infections, or infected wounds, it can also result from viral, fungal, or parasitic infections. Early symptoms include high fever or abnormally low temperature, rapid heart rate, rapid breathing, confusion, and extreme pain or discomfort, which can rapidly progress to severe sepsis with dangerously low blood pressure (septic shock), difficulty breathing, reduced urine output, and altered mental status. Sepsis triggers a cascade of inflammatory responses throughout the body that can damage multiple organ systems including the lungs, kidneys, liver, and heart.

Septic Arthritis

Severe Combined Immunodeficiency (SCID)

Sexually Transmitted Infections (STIs)

Sickle cell anemia

Sjogren's Syndrome

What is Sjögren’s Syndrome? Sjögren’s syndrome is an autoimmune disease that happens when your immune system damages the glands that produce and control moisture in your body. Both sebaceous glands and sweat glands are organs in your body that protect your skin from becoming too dry. Sebaceous glands produce an oily substance called sebum and sweat glands produce a watery substance called sweat. Sweat glands have ducts, which are pathways to excrete substances to the surface of your skin. The main symptoms are dry eyes and mouth, but other parts of the body may be affected as well, with many people reporting fatigue and joint and muscle pain. In addition, the disease can damage the lungs, kidneys, and nervous system. Sjögren’s syndrome predominantly affects women. Sjögren’s syndrome can occur by itself or alongside other autoimmune conditions such as rheumatoid arthritis or systemic lupus erythematosus. There is no cure for Sjögren’s syndrome, but there are several ways to treat and manage the symptoms. What causes Sjögren’s syndrome?

Sleep Apnea

Small intestinal bacterial overgrowth (SIBO)

What Is SIBO? Small Intestinal Bacterial Overgrowth, or SIBO, is a digestive condition marked by an abnormal increase in bacteria levels in the small intestine. This imbalance can lead to various symptoms that may affect your overall wellbeing. The Role of the Small Intestine The small intestine is crucial for nutrient absorption and digestion. It usually harbors fewer bacteria than the colon. When SIBO occurs, this delicate balance is upset, possibly causing significant lifestyle disruptions. Diagnosing SIBO: The Challenge SIBO symptoms often mimic those of other gastrointestinal disorders, such as IBS, making diagnosis complex. The hydrogen breath test is a primary tool for SIBO detection, measuring breath hydrogen levels after a sugar solution is consumed. A significant rise in hydrogen or methane suggests bacterial overgrowth. Contributing Factors to SIBO SIBO can arise from structural small intestine abnormalities, motility issues, or immune system conditions. Medications like PPIs and surgeries can also increase SIBO risk by affecting the gut's environment or structure.

Smoldering Multiple Myeloma (SMM)

What Is Smoldering Multiple Myeloma? Smoldering Multiple Myeloma (SMM), also called asymptomatic myeloma, is an intermediate condition between MGUS (benign) and active multiple myeloma (cancer). Key characteristics of SMM: Higher levels of abnormal protein than MGUS More plasma cells in the bone marrow (10-60%) No symptoms or organ damage No treatment needed yet; active monitoring instead May remain stable for years or progress to active myeloma Important: SMM is not yet cancer requiring treatment. It is a pre-cancerous condition that requires careful monitoring. How SMM Is Diagnosed SMM is diagnosed when the following criteria are met: M protein level: >= 3 g/dL in blood, or >= 500 mg/24 hours in urine Bone marrow plasma cells: 10-60% No symptoms or complications: No bone lesions, anemia, kidney dysfunction, or high calcium (no CRAB features) If symptoms or organ damage develop, the diagnosis changes to active multiple myeloma. SMM vs. MGUS vs.

Spinal Cord Hemorrhage

Statin-Induced Myopathy

Strep Throat (Group A Streptococcal Pharyngitis)

Stroke (young adult)

Subacute Bacterial Endocarditis

Subarachnoid Haemorrhage

Subarachnoid Hemorrhage

Subclinical Hyperthyroidism

Subclinical Hyperthyroidism: Causes, Symptoms, Risks, and Treatment Guide Subclinical hyperthyroidism is a condition where Thyroid-Stimulating Hormone (TSH) levels are below normal, but thyroid hormone levels (Free T3 and Free T4) remain within the normal range. While it may not cause immediate symptoms, subclinical hyperthyroidism can increase risks for heart issues, bone loss, and progression to overt hyperthyroidism if left unmanaged. What is Subclinical Hyperthyroidism? Subclinical hyperthyroidism is defined by: Low or undetectable TSH levels (typically <0.4 mIU/L) Normal Free T3 and Free T4 levels Often no obvious hyperthyroid symptoms It represents an early or mild form of thyroid overactivity that hasn’t yet elevated thyroid hormone levels beyond the normal range but still affects your body’s hormonal feedback loop. What Causes Subclinical Hyperthyroidism? 1. Graves’ Disease (Early Stage) An autoimmune disorder where antibodies stimulate the thyroid gland, causing excess hormone production. 2.

Subclinical Hypothyroidism

Sudden Cardiac Death

Syndrome of inappropriate antidiuretic hormone secretion (SIADH)

Syphilis

Systemic Inflammatory Response Syndrome

Systemic inflammatory response syndrome (SIRS) is a widespread inflammatory reaction throughout the body triggered by various severe insults, including infection, trauma, surgery, burns, pancreatitis, or other major physiological stress. SIRS occurs when the body's immune system becomes overwhelmingly activated, releasing inflammatory chemicals called cytokines that affect multiple organ systems rather than staying localized to the site of injury or infection. The condition is diagnosed when a patient meets at least two of four clinical criteria: body temperature above 100.4°F (38°C) or below 96.8°F (36°C), heart rate greater than 90 beats per minute, respiratory rate greater than 20 breaths per minute or partial pressure of carbon dioxide (PaCO2) less than 32 mmHg, and white blood cell count greater than 12,000 cells/μL or less than 4,000 cells/μL, or more than 10% immature band forms.

Systemic lupus erythematosus (SLE)

What is Systemic lupus erythematosus (SLE)? → Systemic lupus erythematosus is a chronic, multisystem, inflammatory disorder of autoimmune etiology. → SLE is occurring predominantly in young women. → Common manifestations may include arthralgias (joint pain) and arthritis (joint inflammation), Raynaud syndrome (numb & cold fingers/toes), malar and other rashes, pleuritis or pericarditis (chest pains), renal (related to kidneys) or central nervous system involvement, and autoimmune cytopenias (reduced blood cell levels). → Diagnosis requires clinical and serologic criteria. → Treatment of severe, ongoing, active disease requires corticosteroids and immunosuppressants. Systemic lupus erythematosus (lupus) is a chronic (long-lasting) autoimmune disease that can affect many parts of the body. Lupus occurs when the immune system, which normally helps protect the body from infection and disease, attacks its own tissues.

T Cell Lymphoma (differential)

Thalassemia

Thalassemia: An In-Depth Overview Thalassemia is a complex group of inherited blood disorders that significantly impact the body’s ability to produce normal hemoglobin—the essential protein in red blood cells responsible for oxygen transport. This condition leads to anemia, which can range from mild to severe, and typically presents during childhood. Genetic Basis and Pathophysiology At its core, thalassemia is caused by mutations in the genes responsible for hemoglobin production. These mutations result in reduced or absent synthesis of one or more of the globin chains that make up hemoglobin. The imbalance in globin chain production destabilizes red blood cells, making them more prone to premature destruction. This process leads to anemia and a cascade of related health complications, including fatigue, growth delays, and organ damage. Types and Severity The severity of thalassemia depends on the specific type and number of gene mutations involved.

Thrombocytopenia

Thrombocytopenia: Causes, Symptoms, Diagnosis, and Treatment Key Points: Low platelet count symptoms and treatment Thrombocytopenia diagnosis and causes Medications and procedures for low platelet count Complications from untreated thrombocytopenia Autoimmune diseases and platelet destruction What is Thrombocytopenia? Thrombocytopenia is a medical condition characterized by a low platelet count in the blood. Platelets, also known as thrombocytes, are small blood cells produced in the bone marrow that play a crucial role in blood clotting. When an injury occurs, platelets gather at the site to form a clot, preventing excessive bleeding. A healthy adult typically has between 150,000 and 450,000 platelets per microliter of blood. Thrombocytopenia is diagnosed when platelet levels fall below 150,000 per microliter, leading to increased bleeding risk. If left untreated, thrombocytopenia can become life-threatening, particularly if severe internal bleeding or brain hemorrhage occurs. Early diagnosis and treatment are essential for preventing serious complications.

Thrombocytosis

Thrombocytosis: Causes, Symptoms, Diagnosis, and Treatment Thrombocytosis is a medical condition characterized by an abnormally high platelet count in the blood. Platelets are small cell fragments essential for blood clotting and wound healing. This guide covers the types, causes, symptoms, and treatment options for thrombocytosis. What is Thrombocytosis? Thrombocytosis occurs when the platelet count exceeds 450,000 per microliter of blood, as detected through a complete blood count (CBC) test. There are two main types of thrombocytosis: Essential Thrombocythemia (Primary Thrombocytosis): A rare blood disorder caused by overproduction of platelets in the bone marrow, often linked to genetic mutations such as JAK2. Reactive Thrombocytosis (Secondary Thrombocytosis): An elevated platelet count triggered by conditions like infection, inflammation, or surgery. Causes of Thrombocytosis The underlying causes vary depending on the type: Primary Thrombocytosis: Commonly associated with genetic mutations (JAK2, CALR, or MPL).

Thrombophilia

Thymidine phosphorylase deficiency (MNGIE)

Thyroid Cancer Monitoring (Post-Thyroidectomy)

Thyroid cancer monitoring after thyroidectomy involves regular testing and imaging to detect cancer recurrence early when it's most treatable. If you've had your thyroid removed for cancer, you'll need lifelong surveillance using blood tests (primarily thyroglobulin and thyroglobulin antibodies), neck ultrasounds, and sometimes other imaging studies. This monitoring is highly effective—most thyroid cancers are curable, and recurrence can be detected and treated successfully. What thyroid cancer monitoring involves: Regular blood tests to measure thyroglobulin (tumor marker) and thyroglobulin antibodies Periodic neck ultrasounds to visualize the thyroid bed and lymph nodes Thyroid hormone replacement therapy to suppress TSH Risk stratification to determine monitoring intensity Additional imaging (radioiodine scans, CT, PET) when indicated Why monitoring matters: Thyroid cancer can recur months to decades after initial treatment. Regular monitoring allows early detection when recurrence is small and easier to treat.

Thyroiditis

Traumatic Lumbar Puncture

Tubular Nephritis

Type 1 Diabetes

Type 1 diabetes is an autoimmune condition where the body's immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas. This leads to little or no insulin production, which means glucose stays in the blood and can't enter cells to be used for energy. This results in high blood sugar levels, which can lead to various health problems over time. Type 1 diabetes can develop at any age but is most commonly diagnosed in children, teenagers, or young adults. Symptoms include increased thirst and urination, hunger, weight loss, fatigue, and blurred vision. Since the body cannot produce insulin, people with Type 1 diabetes must take insulin every day to survive. The exact cause of Type 1 diabetes is unknown, though it's believed to involve a combination of genetic predisposition and environmental factors that trigger the autoimmune response. There is currently no cure for Type 1 diabetes, but it can be managed through a combination of insulin therapy, diet, exercise, and regular blood sugar monitoring.

Type 2 Diabetes

Ulcerative colitis (UC)

Ulcerative Colitis (UC) is a chronic inflammatory condition confined primarily to the colon and rectum, forming part of a group of conditions known as Inflammatory Bowel Diseases (IBD). It is characterized by the inflammation and continuous ulceration of the mucosal layer of the colon, which distinguishes it from Crohn's Disease, another type of IBD that can affect any part of the gastrointestinal tract and involves deeper layers of the bowel wall. The exact etiology of UC remains unclear, but it is understood to be a complex interplay of genetic predisposition, environmental factors, immune system malfunctions, and alterations in the gut microbiome. Clinically, UC presents with symptoms including persistent diarrhea, rectal bleeding, abdominal pain, and urgency in bowel movements. The severity of these symptoms can range from mild to debilitating, often with periods of remission and exacerbation. Complications may include severe bleeding, perforated colon, and an increased risk of colon cancer, particularly in patients with extensive and long-standing inflammation.

Undifferentiated Connective Tissue Disease

Unexplained prolonged aPTT

Upper Gastrointestinal Bleeding

Upper Respiratory Tract Infection

Urethritis

Urinary tract infection (UTI)

Alternative Names: Bladder infection; UTI; Cystitis bacterial; Pyelonephritis; Kidney infection What is a urinary tract infection? A urinary tract infection is a very common type of infection in your urinary system. It can involve any part of your urinary system. Bacteria — especially E. coli — are the most common cause of UTIs. Symptoms include needing to pee often, pain while peeing and pain in your side or lower back. Antibiotics can treat most UTIs. A urinary tract infection (UTI) is an infection in any part of the urinary system. The urinary system includes the kidneys, ureters, bladder and urethra. Most infections involve the lower urinary tract — the bladder and the urethra. UTIs are common infections that happen when bacteria, often from the skin or rectum, enter the urethra, and infect the urinary tract. The infections can affect several parts of the urinary tract, but the most common type is a bladder infection (cystitis). Are women more at risk to have a urinary tract infection (UTI)? Women are at greater risk of developing a UTI than are men.

Urinary Tract Tuberculosis

Urinary tract tuberculosis (UTTB) is a form of extrapulmonary tuberculosis in which Mycobacterium tuberculosis infects the kidneys, ureters, bladder, or urethra. It is also referred to as genitourinary tuberculosis (GUTB) when the genital organs are involved. UTTB is one of the most common forms of extrapulmonary TB, accounting for up to around a quarter of extrapulmonary TB cases in some series. The condition typically develops years or even decades after an initial lung infection, when dormant bacteria reactivate and spread through the bloodstream to the urinary tract. Because symptoms are non-specific and closely mimic common urological conditions — particularly recurrent urinary tract infections — diagnosis is frequently delayed, which can lead to irreversible kidney and bladder damage. With early detection and full treatment, the cure rate is approximately 90%. How it develops Primary TB infection almost always begins in the lungs. In most people, the immune system contains the bacteria, which remain dormant.

Vaccine-Preventable Disease

Valvular Heart Disease

Vascular dementia

Vascular dementia is a type of dementia caused by reduced blood flow to the brain, which can deprive brain cells of the oxygen and nutrients they need to function properly. This can happen due to blood vessel blockage or damage, leading to strokes or smaller brain injuries over time, which gradually affect thinking, reasoning, and memory capabilities. Vascular dementia is considered the second most common cause of dementia after Alzheimer's disease, and its symptoms can vary widely depending on the areas of the brain affected and the severity of the blood flow disruption. Symptoms often include confusion, difficulty focusing, trouble organizing thoughts or tasks, and problems with memory. Unlike Alzheimer's, which usually begins with memory problems, vascular dementia may start with impaired judgment or the inability to plan. Physical symptoms, such as difficulty walking or a sudden weakness on one side of the body, can also occur, reflecting the brain regions affected by poor blood flow or strokes.

Vasculitides

Vasculitides represents a complex group of health conditions characterized by the inflammation of blood vessels, a process that can lead to significant organ and tissue damage. This umbrella term encompasses various disorders, each affecting different sizes and types of vessels, ranging from large arteries to small capillaries. The inflammation in vasculitides narrows the blood vessels, reducing blood flow and potentially leading to tissue ischemia or necrosis. Symptoms: The symptoms and severity of vasculitides vary widely, depending on the specific vessels and organs involved. Common symptoms include fever, fatigue, weight loss, muscle and joint pain, and in some cases, organ-specific manifestations such as kidney dysfunction, lung problems, or skin rashes. The etiology of vasculitides is multifaceted, often involving a combination of genetic predisposition and environmental triggers, such as infections or drugs, which provoke an aberrant immune response.

Venous thromboembolism (VTE)

Venous thromboembolism (VTE) is a serious health condition that encompasses two related disorders: deep vein thrombosis (DVT) and pulmonary embolism (PE). DVT occurs when a blood clot forms in a deep vein, usually in the legs, which can cause pain, swelling, and redness in the affected area. If a part of this clot breaks off and travels through the bloodstream to the lungs, it can lead to a pulmonary embolism—a life-threatening condition that can obstruct blood flow and oxygen, causing chest pain, shortness of breath, coughing (potentially with blood), and in severe cases, sudden death. Diagnosis of VTE involves a combination of medical history assessment, physical examination, and specialized tests. For DVT, ultrasound imaging is commonly used to visualize blood flow and detect clots in the veins. In suspected cases of PE, computed tomography pulmonary angiography (CTPA) is often the preferred diagnostic tool, as it provides detailed images of the blood vessels in the lungs.

Viral Hepatitis

Viral hepatitis is inflammation of the liver caused by one of several hepatitis viruses. The five main types — hepatitis A, B, C, D, and E — differ significantly in how they are transmitted, how long they last, and what treatment, if any, is needed. Some cause acute illness that resolves on its own; others can become chronic infections that persist for years and lead to serious liver complications if untreated. Viral hepatitis is among the most common causes of liver disease worldwide. Globally, hepatitis B and C account for the majority of chronic liver disease, cirrhosis, and hepatocellular carcinoma. Hepatitis A and E are primarily acute illnesses with fecal-oral transmission, while hepatitis D only occurs in people already infected with hepatitis B. Types of viral hepatitis Hepatitis A (HAV) A self-limiting acute infection transmitted through contaminated food or water. It does not cause chronic liver disease. Most people recover fully within two to three months, and infection confers lifelong immunity. A safe and effective vaccine is available.

Viral Infection

Viral Meningitis

Vitamin B12 Deficiency

Vitamin D Deficiency

Overview Vitamin D deficiency occurs when the body does not have enough vitamin D to support normal bone metabolism, muscle function, and immune regulation. Vitamin D is a fat-soluble vitamin that also acts as a hormone, helping the body absorb calcium and phosphorus and maintain skeletal strength. Because vitamin D is produced in the skin through sun exposure and is found in only a limited number of foods, deficiency is common worldwide—even in otherwise healthy individuals. Why Vitamin D Is Important Vitamin D plays a central role in multiple physiological systems, including: Calcium and phosphorus absorption Bone mineralization and skeletal integrity Muscle strength and coordination Immune system regulation Inflammatory control Low vitamin D levels can affect both short-term health (fatigue, muscle pain) and long-term outcomes (bone loss, fracture risk). Causes of Vitamin D Deficiency Vitamin D deficiency usually results from a combination of reduced production, inadequate intake, or impaired absorption.

Von Willebrand Disease

Waldenström Macroglobulinemia

Wilson's Disease

Wound Infection

X-linked agammaglobulinemia