title: Penicillamine-associated myasthenia gravis.
abstract: Electroneuromyographic studies have been reported as abnormal in only 9 of 23 cases of penicillamine-associated myasthenia gravis (MG). We report a patient with rheumatoid arthritis who developed clinical and electrodiagnostic evidence of myasthenia 7 months after beginning penicillamine therapy. Six months after discontinuing penicillamine, it was possible to discontinue anticholinesterase medications. With clinical improvement, electrodiagnostic studies (including single-fiber electrmyography) improved, serum antibody titers to human muscle acetylcholine receptor fell, and lymphocytes became more responsive to the nonspecific mitogen phytohemagglutinin. Evidence suggests that penicillamine-associated myasthenia is a distinct syndrome rather than the chance occurrence of two diseases. This syndrome is clinically and electrophysiologically distinguishable from idiopathic myasthenia only by the high remission rate after penicillamine is discontinued.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000188:drug therapy; D004576:Electromyography; D005260:Female; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000139:chemically induced* / Q000503:physiopathology; D010396:Penicillamine / Q000009:adverse effects*; D009435:Synaptic Transmission / Q000187:drug effects; D013997:Time Factors
chemical_list: D010396:Penicillamine