EPILEPSY IN PEROXISOMAL DISEASES

Purpose: To clarify the electroclinical manifestation of epileptic sei zures and the evolution of epilepsy in patients with peroxisomal disea ses. Methods. Retrospective review of the medical records and EEGs of 14 patients with peroxisomal diseases: seven with Zellweger syndrome ( ZS), two with neonatal adrenoleukodystrophy (NALD), two with acyl-CoA oxidase deficiency (AOXD), two with bifunctional enzyme deficiency (BF ED), and one with rhizomelic chondrodysplasia punctata (RCDP). The dia gnoses were made by biochemical analysis and pathological examinations in our laboratory, Results. Patients manifested serious neurologic de ficits in the neonatal period or in early or late infancy. Patients wi th ZS or AOXD had partial motor seizures originating in the arms or le gs or corners of the mouth. Their seizures did not culminate in genera lized tonic-clonic seizures and were easily controlled by antiepilepti c drugs (AEDs), Interictal EEGs of the patients with ZS showed infrequ ent bilateral independent multifocal spikes, predominantly in the fron tal motor cortex and its surrounding regions, The EEGs of patients wit h AOXD showed interictal fast theta activity, predominantly in the fro ntocentral regions, Patients with BFED also had partial motor seizures in early infancy, but the seizures were intractable, evolving in one case to myoclonic seizures, Interictal EEGs of patients with BFED show ed bilateral independent multifocal spikes that evolved to bilateral d iffuse high-voltage slow waves in one case and to a hypsarythmic patte rn in another case as the disease progressed, Patients with NALD had i ntractable tonic seizures or epileptic spasms. Interictal EEGs showed high-voltage slow waves and bilateral independent multifocal spikes, e volving in one patient to a flat pattern. The patient with RCDP, whose interictal EEGs showed frequent multifocal independent spikes, did no t have epileptic seizures, Conclusions. The age of epilepsy onset or t he duration of survival is related to the types of seizures occurring in patients with peroxisomal diseases, Neonates or young infants usual ly have partial motor seizures (facial twitching or clonic convulsions of the arms or legs) of various multifocal origins. Older infants may have generalized seizures at the onset of the disease or evolutionall y, Seizure intractability is usually less severe in patients with ZS o r AOXD than in patients with NALD or BFED. There is no relation betwee n the electroclinical characteristics of epilepsy and the genetic comp lementation groups in peroxisomal diseases.