Paroxysmal dystonia as the initial manifestation of multiple sclerosis.

Paroxysmal dystonia was the initial manifestation of multiple sclerosis (MS) in eight patients. The disorder was generally characterized by dystonic posturing of unilateral extremities, averaging less than one minute in duration. Facial grimacing and dysarthria occurred in two of the eight patients. This paroxysmal phenomenon was frequently the cause of diagnostic confusion. The time elapsing before other neurological symptoms of MS developed was as long as ten years.