The Extractable Nuclear Antigen (ENA) Screen, often referred to as an ENA panel, is a diagnostic blood test designed to detect specific autoantibodies in the bloodstream. These autoantibodies are proteins produced by the immune system that mistakenly target and attack the body's own healthy tissues, rather than foreign invaders like bacteria or viruses. Identifying these autoantibodies is crucial for diagnosing certain autoimmune diseases.

The ENA (Extractable Nuclear Antigens) to Smith (Sm) antibody test plays a pivotal role in the field of autoimmune diagnostics, particularly in the context of systemic lupus erythematosus (SLE). Smith antibodies are a subset of antinuclear antibodies (ANAs), specifically targeting proteins found within the cell nucleus, known as Sm antigens. These antigens are integral to the splicing of pre-mRNA, making them vital for cell function.

In autoimmune conditions like SLE, the body's immune system mistakenly targets its own tissues, with Smith antibodies being one of the markers of this aberrant immune response. The presence of Smith antibodies is considered highly specific for SLE; while they are not found in all patients with SLE, their presence is rarely observed in other diseases. This specificity makes the ENA to Sm antibody test an invaluable tool in the differential diagnosis of SLE, distinguishing it from other autoimmune disorders that may present with similar symptoms.

The ENA-6 Reflexed test is a blood test used to help diagnose autoimmune diseases, particularly those that affect the connective tissues, such as Systemic Lupus Erythematosus (SLE), Sjögren's syndrome, scleroderma, and polymyositis. "ENA" stands for Extractable Nuclear Antigens, which are proteins found inside the nucleus of cells that can become targets of the immune system in autoimmune diseases. The "6" refers to six specific antigens included in this panel: SS-A (Ro), SS-B (La), Sm, RNP, Scl-70, and Jo-1. Each of these antigens is associated with different autoimmune conditions, and identifying antibodies against them can provide valuable clues for diagnosis. For example, antibodies against SS-A and SS-B are often found in patients with Sjögren's syndrome, while antibodies against Sm are highly specific for SLE.

Epidemiology:

- Fecal contamination of food or water

Clinical Implications:

- Considered non-pathogenic; individuals may be asymptomatic

- May be indicative of dysbiosis, conservative treatment may be indicated if clinical presentation is consistent with enteroparasitosis.

This test looks for certain antibodies in your blood that may mean you have celiac disease, an autoimmune disease.

Presence of the tissue transglutaminase (tTG) IgA antibody is associated with gluten-sensitive enteropathies such as celiac disease and dermatitis herpetiformis.

The "Endomysial Antibody Screen (IgA) with Reflex to Titer" is a specific blood test often used to help diagnose celiac disease, an autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. This test looks for antibodies against a type of tissue in your body known as endomysium, which is a layer surrounding each muscle fiber. IgA refers to Immunoglobulin A, a type of antibody found in mucous membranes and blood, playing a crucial role in the immune function of mucous membranes. If this initial screening test detects the presence of endomysial antibodies (EMA), it typically indicates an immune response triggered by gluten consumption in individuals with celiac disease. The "reflex to titer" part means that if the initial screen is positive, the laboratory will automatically perform further testing to determine the concentration of antibodies (titer). This additional step helps gauge the severity of the disease and can be useful in monitoring how well a patient is adhering to a gluten-free diet, which is the primary treatment for managing celiac disease. A higher titer indicates a higher concentration of antibodies, suggesting a more significant immune response to gluten. Understanding the results of this test can be pivotal in diagnosing celiac disease accurately, enabling individuals to adopt necessary dietary changes to improve their health and quality of life.

The Endomysial Antibody Titer is a crucial diagnostic tool in the evaluation of celiac disease and related gluten-related disorders, aiding in early diagnosis and appropriate management.

Enniatin B is a fungal metabolite categorized as cyclohexa depsipeptides toxin produced by the fungus Fusarium. This strain of fungus is one of the most common cereal contaminants.

Entamoeba coli are intestinal amebae that are found in the large intestine. They generally are not considered pathogenic. However, when these amebae are found in stool samples it can indicate the presence of other potentially pathogenic organisms.

E. histolytica invasion may contribute to T-helper-2 bias and antibody production particularly against E. histolytica lectins and their association with tissue antigens such as phospholipids, actin and ANCA. By penetrating the intestinal tissues, E. histolytica is able to disturb tight junction assemblies, thereby opening the intestinal tight junctions and putting the body at risk for autoimmunity. Once in the bloodstream, E. histolytica may trigger autoimmunity against neurological or bone tissues, due to its homology with gangliosides and skeletal actin.

Epidemiology:

→ Fecal contamination of ingested foods or water

→ Pets may be a source of exposure

→ Sexual contact may be a source of exposure

Clinical Implications:

→ Symptoms include diarrhea, fulminating colitis (resembling ulcerative colitis), and dysentery

→ Extreme cases may invade liver and lung tissues