Typical and atypical forms of paroxysmal choreoathetosis.

Two children with clinical pictures of paroxysmal kinesinogenic choreoathetosis and paroxysmal dystonic choreoathetosis are described and compared with previous reports with regard to diagnostic procedures, therapeutic approach and prognosis. A third case, characterized by paroxysmal dyskinesia induced by exercise and associated with choreiform nonprogressive signs, is also described. Such an association has not been reported previously. This unusual clinical picture indicates the possibility of intermediate forms in the paroxysmal choreoathetosis group and suggests a relationship between paroxysmal motor disorders and benign familial chorea with early onset.