Myasthenia Gravis Profile
Performed by: LabCorp
What Is the Myasthenia Gravis Profile?
The Myasthenia Gravis (MG) Profile is a blood test panel used to help diagnose myasthenia gravis, a chronic autoimmune disorder that affects the connection between nerves and muscles. This condition causes muscle weakness, especially in the eyes, face, throat, and limbs, and symptoms often get worse with activity and improve with rest.
The MG Profile looks for specific autoantibodies that interfere with normal muscle activation, helping doctors confirm or rule out the diagnosis.
Why Is This Test Important?
Myasthenia gravis can sometimes be difficult to diagnose based on symptoms alone, especially in its early stages. The MG Profile detects antibodies that are highly specific to this disease, enabling a more accurate diagnosis and helping guide treatment decisions.
What Does the MG Profile Measure?
The panel may include testing for one or more of the following antibodies:
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Acetylcholine Receptor (AChR) Antibodies
The most common antibodies in MG, targeting receptors that help muscles receive nerve signals. -
Muscle-Specific Kinase (MuSK) Antibodies
Found in a smaller subset of patients, particularly those who are AChR antibody-negative but still have MG symptoms. -
LRP4 Antibodies (optional or separate in some panels)
Seen in some cases of MG not explained by AChR or MuSK antibodies.
Who Should Get This Test?
Your healthcare provider may order the MG Profile if you have symptoms such as:
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Drooping eyelids (ptosis)
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Double vision (diplopia)
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Slurred speech
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Difficulty swallowing
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Weakness in the arms, legs, or neck
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Muscle fatigue that worsens with activity
What Do the Results Mean?
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Positive for AChR, MuSK, or LRP4 antibodies:
This supports a diagnosis of autoimmune myasthenia gravis. Treatment with medications that improve nerve-muscle communication or suppress the immune system may be recommended. -
Negative result:
A negative test does not completely rule out MG. Some individuals with classic symptoms may not have detectable antibodies. In such cases, your doctor may perform additional testing, such as EMG (electromyography) or a single-fiber EMG to assess nerve and muscle function directly.
How Is the Test Performed?
It’s a simple blood draw, usually done at a laboratory or medical office. No special preparation is needed.
Summary
The Myasthenia Gravis Profile is a crucial tool for diagnosing this rare autoimmune neuromuscular disease. By detecting antibodies that disrupt communication between nerves and muscles, it helps doctors identify MG early and begin appropriate treatment—potentially improving symptoms and quality of life.
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Biomarkers included in this panel:
The AChR Binding Antibodies, Serum test measures the presence of autoantibodies against acetylcholine receptors (AChRs) in the blood. These antibodies interfere with the normal communication between nerves and muscles and are commonly associated with
Learn moreWhat Are AChR Blocking Antibodies? AChR Blocking Antibodies are a type of autoantibody that interfere with how acetylcholine receptors (AChRs) work at the neuromuscular junction—the place where nerves signal muscles to contract. These antibo
Learn moreWhat Is the AChR-Modulating Antibody? The AChR-Modulating Antibody test detects autoantibodies that disrupt communication between nerves and muscles by targeting and altering acetylcholine receptors (AChRs) on muscle cells. These antibodies are co
Learn moreWhat Is the MuSK Antibodies Test? The MuSK Abs, Serum test detects antibodies against Muscle-Specific Kinase (MuSK) in your blood. These antibodies are associated with a type of autoimmune myasthenia gravis (MG)—a condition that causes muscl
Learn more