Longitudinal multimodal evoked potential studies in abetalipoproteinaemia.

Recent studies have reported that in abetalipoproteinaemia patients high dose vitamin E therapy may arrest or improve the neurological syndrome. Five patients with abetalipoproteinaemia have been followed since 1982, when all were started on high dose vitamin E therapy. Auditory brainstem responses (ABR), visual evoked potentials (VEP), and sensory evoked potentials (SEP) were recorded every six to twelve months. The vitamin E levels stayed below normal range in all patients; the neurological status remained relatively stable in most of the patients over the four years. The ABRs were consistently normal in all patients over the period of study. The VEPs improved in one patient with introduction of vitamin E therapy, and remained stable in the others, one of whom always had abnormal VEPs. The cortical SEPs were abnormal in all but the least affected patient and fluctuated in the two patients who also demonstrated some deterioration in neurological status. These results suggest that serial assessments combining neurological and neurophysiological studies provide important information in the follow-up of patients with abetalipoproteinaemia and that the SEP is the evoked potential best suited for the detection of the neurological changes in this disorder.