[Paroxysmal dyskinesias in children]

The clinical, pathophysiological and genetic features of some of the paroxysmal movement disorders are reviewed. Paroxysmal idiopathic dyskinesias are genetically heterogeneous. Although some motor manifestations of epilepsy and paroxysmal dyskinesia may be difficult to differentiate clinically, the current understanding is that the two disorders are clinically distinct. However there are several recent reports of families in which different individuals have either disorder or both manifestations, with age-related expressions. Co-occurrence makes it likely that a common, genetically determined pathophysiologic abnormality is variably expressed in the cerebral cortex and in basal ganglia.

The pathophysiology of paroxysmal dyskinesia is unknown. To date, despite strong suspicions, no ion channel gene mutations have been isolated.