Acetylcholine receptor Ab

Keywords: Acetylcholine receptor antibody, AChR Ab, Myasthenia gravis antibody, AChR antibody

Specimen:

5 mL blood in plain tube on melting ice, or blood spots on kit filter paper.

Method:

Competitive binding assay using radio-labelled alpha-bungarotoxin acetylcholine receptor. Radio-immunoassay using cell lines.

Reference Interval:

Qualitative test. Positive result is significant.

Application:

Diagnosis of Myasthenia gravis.

Interpretation:

More than 90% of patients with generalised myasthenia gravis and about 60% of those with ocular myasthenia have detectable acetylcholine receptor antibodies. The test is positive in fewer than 1% of non-myasthenic individuals and a positive result usually indicates a related disorder.

Reference:

Drachman DB. N Engl J Med 1994; 330: 1797-1810.