Mitochondrial encephalomyopathy lactic acidosis and strokelike episodes mimicking occipital idiopathic epilepsy.

We report on a 19-year-old man with a 9-year history of occipital seizures characterized by deviation of the eyes and tonic ipsilateral turning of the head during sleep, initially diagnosed as idiopathic childhood occipital epilepsy, Gastaut type. The eventual development of status epilepticus, associated with a T(1) hypointense as well as T(2), fluid-attenuated inversion recovery, and diffusion-weighted hyperintense brain lesion led to pathologic and genetic testing that identified a A3243G mitochondrial DNA point mutation associated with mitochondrial, encephalomyopathy, lactic acidosis, and strokelike episodes. This case emphasizes that occipital epileptic seizures can be the only presenting and long-lasting sign in patients with mitochondrial, encephalomyopathy, lactic acidosis, and strokelike episodes.