[Orthostatically induced epileptoid attack].

Abstract

An epileptoid attack induced by orthostatic hypotension seen in a 72-year-old man was reported. The patient had been suffering from progressive autonomic failure with parkinsonism for six years and he had severe orthostatic hypotension, syncope and generalized convulsion when he stood up. The convulsion sometimes associated with urinary incontinence, ceased immediately when he lay down although he remained drowsy for a while. Occasionally the seizure ceased spontaneously and he regained consciousness even while he was kept standing. On lying position his blood pressure was 167/88 mmHg and no abnormality was seen in electroencephalogram. When he was tilted up to 50 degrees his blood pressure fell to 70/46 mmHg, and he became unconscious followed by jaw twitching and generalized clonic seizure. Electroencephalogram during seizure showed sharp wave and rhythmic spikes. Other laboratory examination revealed diffuse and severe autonomic dysfunction and slight cerebral atrophy on brain CT scanning. He was treated with diphenylhydantoin 300 mg/day and the seizure responded partially. The reasons why the patient's seizure was thought to be epileptic rather than the convulsive syncope were as follows: the type of the seizure was similar to an epileptic generalized convulsion, the seizure and unconsciousness ceased spontaneously even during standing position, the seizure and impaired consciousness partially responded to diphenylhydantoin administration. The underlying pathophysiology of the seizure was thought to be transient cerebral hypoperfusion induced by orthostatic hypotension.