Essentials in the management of myasthenia gravis.

Myasthenia gravis is a disorder that most commonly affects young adults but occasionally appears in the elderly. Muscle weakness and easy fatigability, particularly of the ocular muscles, are characteristic. Diagnosis is confirmed by electromyography and the edrophonium (Tensilon) test. The pathology results from inability of acetylcholine to gain access to receptor sites at the neuromuscular junction, possibly because of a blocking antibody produced by the thymus. Initial treatment (in the absence of a thymoma) consists of administration of an anticholinesterase drug. If that is ineffective, thymectomy and/or corticosteroids may be useful.