A rare progressive neurodegenerative disorder characterized by mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes.

MELAS (Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes) is one of the family of mitochondrial diseases, which also include MIDD (maternally inherited diabetes and deafness), MERRF syndrome, and Leber's hereditary optic neuropathy. It was first characterized under this name in 1984...