Epilepsy and paroxysmal movement disorders in families: evidence for shared mechanisms

The epilepsies have been regarded as clinically distinct from the paroxysma l movement disorders. Recently, a variety of ion channel defects have been identified as the biological basis of certain familial epilepsies and parox ysmal movement disorders. We studied two families with the cooccurrence of epilepsy movement disorders and migraine. Information was obtained on 147 individuals in the two families. In family WF, there was a co-occurrence of epilepsy (benign infantile convulsions, id iopathic generalized epilepsy), episodic ataxia (with cerebellar atrophy an d without myokymia) and common migraine. In family CL, epilepsy (febrile se izures, febrile seizures plus), kinesigenic paroxysmal dyskinesia and migra ine (including hemiplegic migraine) were observed in various combinations o ver 3 generations. The observations in these two families, together with review of the literat ure, suggest that the co-occurrence of epilepsy (particularly benign infant ile convulsions), paroxysmal movement disorders and migraine is not due to chance. Thus, these distinct clinical phenomena could have a shared biologi cal basis and ion channel defects are an attractive possibility.