Acetylcholine Receptor (AChR) Antibodies, Quantitative, Serum

Myasthenia gravis is a potentially serious but treatable organ specific autoimmune disorder characterised by weakness and fatigability of the voluntary muscles. It is caused by auto antibodies against the nicotinic acetylcholine receptor (AChR) on the postsynaptic membrane at the neuromuscular junction.

AChR antibody testing is useful in the diagnosis of myasthenia gravis. The incidence of AChR antibodies in patients with generalised myasthenia is around 87% and is between 50-60% in ocular myasthenia (weakness of the muscles of the eye). Antibody values do not correlate with disease severity across the patient population. However, in an individual patient, the titre does correlate with the disease severity and a decrease in titre means favourable response to treatment. Decreased Acetylcholinesterase activity is associated with hairy cell leukaemia and other types of leukemia and thrombocytopenia. Increased activity is associated with Alzheimer's disease.

1 ml Serum Room Temperature

Avoid prolonged tourniquet use.

Negative: < 0.25 nmol/L Equivocal: 0.25 - 0.4 nmol/L Positive: > 0.4 nmol/L