Abstract

MELAS(mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes) syndrome is a rare cause of mitochondrial encephalomyopathy, with variable clinical features, such as encephalomyopathy, lactic acidosis, stroke, diabetes, short stature, sensorineural hearing loss and basal ganglia calci-fication, etc. It can be confirmed by molecular genetic analysis that reveals the mitochondrial A3243G point mutation. Among the clinical manifestations in MELAS syndrome, diabetes mellitus is associated with impaired insulin secretion and often misdiagnosed type 1 diabetes. Herein, a rare case for the MELAS syndrome, with diabetes mellitus that came from ketoacidosis, is introduced. A 21-year-old woman, carried to the emergency department had a stuporous mentality. She was thin(BMI 16.1kg/m(2)), and had difficulty with her hearing capacity. According to the initial laboratory results, she showed the metabolic acidosis, hyperglycemia, ketonemia, and ketonuria. She was diagnosed as diabetic ketoacidosis and treated with insulin and hydration. Brain imaging from MRI, and a CT scan showed basal ganglia calcification, hemorrhagic infarction and diffuse brain atrophy. The markers for beta-cell autoimmunity were negative. Her electromyography suggested proximal myopathy. In addition, a molecular genetic analysis identified A3243G point mutation in the peripheral blood leukocytes from her, her mother and her sister.

• Keywords: MELAS syndrome;Diabetes mellitus;Diabetic ketoacidosis