[A case of MELAS with G13513A mutation presenting with chronic kidney disease long before stroke-like episodes]

The patient was a 35-year-old female with an 9-year history of chronic kidney disease awaiting renal transplantation. She was brought to hospital by ambulance due to a generalized convulsive seizure. Her consciousness remained disturbed after treatment for her seizure, and sensorineural deafness was noted. Lactic acid and pyruvic acid levels were extremely elevated in both the plasma and the cerebrospinal fluid, and brain atrophy was obvious on brain imaging. These findings suggested mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes, which was confirmed by muscle biopsy. Previous renal biopsy specimen showed focal segmental glomerulosclerosis and granular swollen epithelial cells. She had no acute progression of the stroke-like episode with L-arginine treatment. However, the brain lesions expanded on MRI. Mitochondrial DNA analysis from a muscle biopsy specimen showed G13513A mutation. The G13513A mutation and the long history of preceding renal failure before the stroke-like episodes were distinctive features in this case.