Association of neuromyotonia with peripheral neuropathy, myasthenia gravis and thymoma: a case report.

A case of neuromuscular hyperactivity syndrome associated with a thymoma, high serum titres of anti-acetylcholine receptor and anti-DNA antibodies is reported. The study of peripheral nerve conduction revealed a peripheral neuropathy. Repetitive stimulation showed a decrease in the fifth M response. Myasthenic symptoms were anamnestically reported but were absent at clinical observation. The clinical picture and EMG examination improved after phenytoin administration.