Adult-onset Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke (MELAS)-like Encephalopathy Diagnosed Based on the Complete Sequencing of Mitochondrial DNA Extracted from Biopsied Muscle without any Myopathic Changes

• Published in: Internal Medicine Vol. 56; no. 1; pp. 95 - 99
• Main Authors: Mukai, Masako, Nagata, Eiichiro, Mizuma, Atsushi, Yamano, Mitsuhiko, Sugaya, Keizo, Nishino, Ichizo, Goto, Yu-ichi, Takizawa, Shunya
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Internal Medicine 01.01.2017; Japan Science and Technology Agency
• Subjects: Acidosis; Acidosis, Lactic - diagnosis; Acidosis, Lactic - genetics; Adult; adult onset; Biopsy; Brain Diseases - diagnosis; Brain Diseases - genetics; Case Report; Defects; DNA sequencing; DNA, Mitochondrial - genetics; Early Diagnosis; Electron transport chain; Encephalopathy; Genetics; Genomes; Humans; Internal medicine; Lactic acidosis; m.10158T>C mutation; Male; MELAS; MELAS syndrome; MELAS Syndrome - diagnosis; MELAS Syndrome - genetics; Mitochondrial DNA; Mitochondrial Myopathies - diagnosis; Mitochondrial Myopathies - genetics; MT-ND3; Muscles; Muscular Diseases - genetics; Muscular Diseases - pathology; Mutation; Myopathy; NADH-ubiquinone oxidoreductase; Nucleotide sequence; Stroke-like episodes
• ISSN: 0918-2918; 1349-7235
• DOI: 10.2169/internalmedicine.56.7301

The clinical features of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) are not uniform. We herein report a male patient with unusual MELAS-like encephalopathy who had been experiencing isolated recurrent stroke-like episodes since he was 33 years old without any particular family history. Despite an extensive investigation, he had no other signs suggestive of MELAS. Although the muscle pathology showed a normal appearance, a mitochondrial genome sequence analysis of the biopsied muscle revealed a heteroplasmic m.10158T>C mutation in the mitochondrial complex I subunit gene, MT-ND3. To prevented further deterioration of the higher brain function, the early diagnosis and treatment of mitochondrial stroke-like episodes is important.