Paroxysmal non-kinesigenic dyskinesia due to a PNKD recurrent mutation: report of two Southern European families.

Paroxysmal non-kinesigenic dyskinesia (PNKD) is an autosomal dominant disorder characterized by attacks of dystonic or choreathetotic movements precipitated by stress, fatigue, coffee, alcohol or menstruation. In this report we present two families with PNKD of Southern European origin carrying a PNKD recurrent mutation. Incomplete penetrance and intrafamilial variability was detected in both families. Treatment with valproic acid and levetiracetam provided favorable response.