Coma with abnormal movements and prolonged cognitive disturbances: a new subset of acute encephalopathy.

We describe two children who presented with an acute encephalopathy preceded by a prodromal illness. The disease was marked by an active phase of coma or confusion with abnormal motor movements, followed by a recovery phase with a rapid return of motor function and a gradual improvement in speech and social behavior. No cause was found. These may be additional representative cases of a new syndrome of encephalopathy which is characterized by a distinctive course and a relatively good prognosis.