New epilepsy seizure at high altitude without signs of acute mountain sickness or high altitude cerebral edema.

Neurological disturbances may be present at high altitude independently of high altitude cerebral edema. We report here the case of a patient who experienced for the first time generalized seizures after spending a night at an altitude of 5200 m, with no preceding symptoms of acute mountain sickness. An initial CT scan performed 12 hours after his loss of consciousness and an MRI scan performed 2 months later were normal. An EEG, obtained 2 months after the event, showed epileptiform discharges triggered by hyperventilation. The description of the clinical event obtained from the witness and the presence of a positive family history strongly support a high altitude-triggered new epileptic seizure. This report suggests that at high altitudes seizure risks in a seizure-prone person may be higher than for normal individuals.