[Persistent cerebellar ataxia after toxic administration of diphenylhydantoin]

Diphenylhydantoin (DFH) is known to yield cerebellar ataxia in chronically treated epileptic patient due to cerebellar atrophy with loss of Purkinje cells. Little attention has been paid in the literature to the acute DFH intoxication bearing cerebellar symptoms. We report a patient afflicted with complex partial seizures due to a left temporal cyst, who has been treated during the last two years with DFH 100 mg/day. Due to the refractory characteristics of his seizures he was put on DFH 400 mg daily, and developed a pancerebellar syndrome. After surgical removal of the cyst his seizures entirely faded away and his cerebellar signs improved. Nevertheless his neurological examination still showed trunkal and lower limbs ataxia. After one year of follow up his neurological picture did not change, while he was seizures free. TC and MRI did not show cerebellar atrophy.