[Is there true remission in myasthenia gravis? Long-term clinical and electrophysiological studies]

Twenty myasthenic patients were followed up who had in the years 1981-1982 full clinical remission (no drugs, no symptoms), lasting at that time at least several years. However, in 19 of them neuromuscular transmission defects were then found by single fibre electromyography (SFEMG). We then concluded that true remissions did not exist in myasthenia (J. Neurol., 1985, 231, 331). Recently, we were able to evaluate those patients. One patient, who had full long lasting remission after thymomectomy, died at the age of 69 of myocardial infarction in the course of a myasthenic relapse. Another patient had a relapse, 20 years after thymoma extirpation. Two patients had recurrent fluctuating relapses of myasthenia. One patient, who had undergone thymectomy in his childhood, developed immune thrombocytopenic syndrome. SFEMG done in 12 patients showed abnormalities in 5 cases only (mean jitter elongation, increased percentage of potential pairs with blocking and jitter elongation more than 55 microseconds). In 7 remaining patients the catamnesis covering more than 14 years revealed full clinical and electrophysiological remission. Thus, repeated analysis of the group of myasthenic patients with remission has lead us to revise our former opinion that there are no true remissions, clinical and electrophysiological, in myasthenia. They certainly occur but in some patients normalization of the electrophysiological pattern appears only several years after they have become clinically asymptomatic.