Myasthenia Gravis Reflexive Panel

Casandra

Casandra Test Code AR36040Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 3001869CPT Codes 86041, 86042, 86043, 86256, 86366

Myasthenia Gravis Reflexive Panel

Also known as: MG R PAN

Clinical Use

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Use

The Myasthenia Gravis Reflexive Panel assists in establishing or confirming a clinical diagnosis of myasthenia gravis by testing for antibodies associated with this condition. Approximately 85-90% of patients with myasthenia gravis express antibodies to the acetylcholine receptor (AChR), including binding, blocking, and modulating antibodies. These antibodies can impair neuromuscular transmission, leading to muscle weakness. The panel utilizes a reflexive approach where initial findings may prompt additional antibody testing, ensuring a comprehensive assessment.

Special Instructions

If Acetylcholine Receptor Binding Antibody result is greater than 0.4 nmol/L or Acetylcholine Receptor Blocking Antibody result is greater than 26 percent, then Acetylcholine Receptor Modulating Antibody will be added. If Acetylcholine Receptor Binding Antibody result is less than or equal to 0.4 nmol/L, then Muscle-Specific Kinase (MuSK) Antibody will be added. Additional charges apply for reflex testing.

Limitations

The test has a limitation in that approximately 10-15% of individuals with confirmed myasthenia gravis may not express measurable binding, blocking, or modulating antibodies. Negative test results do not rule out the diagnosis of myasthenia gravis, as some patients may have antibodies that are not detected by the available assays. Clinical correlation is required to interpret test results accurately.

Test Details

New York Approved