Therapeutic strategies for myasthenia gravis

Myasthenia gravis (MG) is a complex autoimmune neurologic disorder of unknown etiology, characterized by fluctuating skeletal muscle weakness most commonly involving the muscles of the head, neck, and upper extremities. Autoantibodies directed against acetylcholine receptors on the postjunctional membrane decrease the numbers of functional acetylcholine receptors and cause membrane alterations, resulting in neuromuscular transmission failure. Diagnosis is established by history and physical examination, the "Tensilon Test," and acetylcholine receptor antibody titers. Treatment modalities include drug therapy, thymectomy, and plasmapheresis. The drugs most commonly employed are anticholinesterases, corticosteroids, and immuno-suppressive agents. Cyclosporine and intravenous immunoglobulin are promising investigational treatments. The purpose of the article is to review current concepts in the pathophysiology, immunopathology, diagnosis, and treatment of MG. Special emphasis is placed on the autoimmune form of the disease and the drugs employed in its management. Standard regimens as well as some experimental treatment modalities are reviewed.