Connatal Leigh Disease

Two children are described with pathology-proven Leigh disease. Rather than the typical degenerative course with loss of acquired development, they presented with a static encephalopathy manifested by seizures from birth and failure to acquire any milestones. A similar connatal presentation has been reported in other degenerative disorders, such as Pelizaeus-Merzbacher disease. Heredodegenerative disorders should be considered when no cause is discovered for a severe, congenital, static encephalopathy.