[Treatment of autoimmune myasthenia]

Myasthenia gravis is the most common neuromuscular junction disorder and the best understood autoimmune disease of the nervous system. The autoimmune attack leads to decreased concentrations of the AChR and results in fatigability of skeletal muscles increasing with activity and improving with rest. The treatment of myasthenia has improved dramatically over the last few decades, with an increasing number of immunotherapies used in management although not all of them have been formally tested in double-blind, prospective trials. The principles of treatment consist in optimizing neuromuscular junction function by use of cholinesterase inhibitors, inducing an immunologic remission and then maintaining that remission by long-term immunotherapies. Prednisone and/or azathioprine are the most effective. Short-term immunotherapies, i.e. intravenous immunoglobulin or plasmapheresis, are indicated for disease exacerbation. For patients with nonthymomatous autoimmune myasthenia, the effectiveness of thymectomy remains uncertain. The overall objective of therapy is to enable patients to lead a normal life as rapidly as possible, while limiting side effects and costs if possible. Treatment should be individualized. The aggressiveness of therapy should be balanced against a number of factors including distribution of muscle involvement, rate of progression, degree of functional impairment, lifestyle choice, and coexisting disease. In all cases, adequate education, for the patient and the physician, is most helpful in facilitating management of this chronic disease.