An autopsy case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes syndrome with chronic renal failure.

A 25-year-old man developed a stroke-like episode. He suffered from renal failure and became dialysis-dependent. His mother was also dialysis-dependent. A3243G point mutation of the mitochondrial tRNA(leu) gene was detected in both of them. The patient was diagnosed with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), and died of a recurrence of stroke-like episodes at the age of 30. Autopsy revealed numerous abnormal mitochondria in the kidneys, but no renal vascular changes. This is the first report of a MELAS case in which the presence of numerous abnormal mitochondria in podocytes and tubules was confirmed by electron microscopy.