A 34-year-old man presented with headache, double vision, and seizures for 1 month and altered consciousness for 1 week. He had had 2 episodes of seizures that were characterized by tonic head and eye deviation to the left, followed by a brief period of tonic-clonic activity of all 4 limbs and postictal confusion for 10 to 15 minutes. He denied a history of fever, head trauma, limb weakness, or vomiting. He was a vegetarian, nonsmoker, and nondrinker. He denied a history of drug addiction.