Paroxysmal kinesigenic choreoathetosis because of cryptogenic myelitis. Remission with carbamazepine and the pathogenetic role of altered sodium channels

Lesions of the spinal cord causing paroxysmal kinesigenic choreoathetosis are rare and most of the reported cases have been because of multiple sclerosis. We now describe this movement disorder occurring in a patient who developed a myelitis of unknown aetiology. A typically striking remission followed treatment with carbamazepine. It is suggested that the effect of the drug and the disorder itself may both be explained on the basis of altered sodium channels.