Serologic profile of myasthenia gravis and distinction from the Lambert-Eaton myasthenic syndrome

Publisher Website
Google Scholar
Abstract
Article abstract-Autoimmune serologic testing is indicated in the initial investigation of a patient believed to have myasthenia gravis (MG) or the Lambert-Eaton myasthenic syndrome (LES). Serologic confirmation of mild, ocular, or recent-onset MG is ensured by a panel of antibody tests more than by any single test, and by testing before commencing immunosuppressant therapy. A positive result for the acetylcholine receptor (AChR)-binding antibody test is characteristic but not diagnostic of MG. AChR-binding or striational autoantibodies are found in 13% of patients with LES, a disorder that tends to be mistaken for MG when the presenting symptoms include ocular or bulbar muscle weakness. Seropositivity for P/Q-type calcium channel-binding antibodies distinguishes these disorders (LES 95%; MG 90% AChR loss. Results of all serologic tests must be interpreted by a physician in the context of a patient's history, physical and electromyographic findings, response to Tensilon, chest imaging, and other serological findings (e.g., striational antibodies, thyroid and gastric autoantibodies, and P/Q-type calcium channel-binding antibodies). NEUROLOGY 1997;48(Suppl 5): S23-S27