Edrophonium test is diagnostic of: (A) Myasthenia gravis, (B) Lambert Eaton syndrome, (C) Ammyotropic lateral sclerosis, (D) All
Answer is A. Ans. a (Myasthenia gravis). (Ref. Harrison, Internal Medicine, 16th ed., 2519)Test for diagnosis of MGCommentsAcetyl Choline Esterase/Tensilon/EdrophoniumTest# Most commonly used rapid test.# Highly probable diagnosis if unequivocally positive.# False positive in ammyotropic lateral sclerosis and placebo reactorsAnti-Ach receptor ab assay# 85% positivity in generalized myasthenia gravis.# 50% positivity in ocular myasthenia gravis.# Definitive diagnosis if positive.Repetitive nerve stimulation test# Highly probable.Single fiber EMG# Confirmatory but non-specific