Subacute necrotizing encephalomyelopathy (Leigh disease): report of a case with Lennox-Gastaut syndrome.

More than 100 cases of Leigh disease have been reported. None have shown Lennox-Gastaut syndrome. We report here the first known case of Leigh disease with Lennox-Gastaut syndrome, and discuss the clinical course in detail. A 3 1/2-year-old-boy was admitted with multiple symptoms and despite various therapies he died at age of ten years. Serial CT showed marked cerebral atrophy, ventricular dilatation, and an arachnoid cyst in the posterior fossa. Histopathological findings on autopsy of the brain and spinal cord were consistent with those characteristic of Leigh disease. In the chronic course of Leigh disease, the cerebral cortex was also involved and the Lennox-Gastaut syndrome might be complicated.