Episodic encephalopathy with dilated pupils

Abstract

Recurring transient partial or complete loss of consciousness can result from toxic, metabolic, or vascular encephalopathy or structural brain damage. Migraine, epilepsy, and abnormal sleepiness (e.g., narcolepsy or Kleine–Levin syndrome1) also cause similar unresponsiveness. A transient increase in benzodiazepinelike activity has been reported to produce idiopathic recurring stupor.2 Described here is a patient with a novel recurring transient consciousness disturbance of unknown origin unrelated to these causes; the episodes were associated with pupillary dilatation, hyperthermia, and tachycardia. A man, 42 years of age without a family or personal history of psychiatric or neurologic illnesses, was hospitalized for decreased alertness. A few hours later, his condition rapidly deteriorated into confusion with dysarthria, and he was referred to our hospital. At examination, he was stuporous and his pupils were dilated …