The clinical history and neurological examination provide the most important data
on which the diagnosis of autoimmune myasthenia gravis (MG) is based. MG produces
symptomatic weakness that predominates in certain muscle groups and typically fluctuates
in response to effort and rest. The diagnosis of MG therefore depends on the recognition
of this distinctive pattern of fatigable weakness. Laboratory confirmation of the
clinical diagnosis may be obtained using pharmacological, electrophysiological, and
serological (immunological) tests. This article reviews the tests used to confirm
the diagnosis of MG.
KEYWORDS
Acetylcholine receptor antibody - repetitive nerve stimulation - single-fiber electromyography
- edrophonium chloride
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Matthew N MeriggioliM.D.
Department of Neurological Sciences, Rush University
1725 W. Harrison Street, Suite 1106, Chicago, IL 60612