Mitochondrial encephalopathy with lactic acidosis and stroke-like episodes in a Japanese child: Clinical, radiological and molecular genetic analysis

Abstract

Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes is a mitochondrial multisystem disorder. This disease has mainly been associated to the mitochondrial DNA mutation A3243G located in the tRNA Leucine gene. In this article, we report the clinical, radiological and molecular results of a 10 years old Child with the classical Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes phenotype. A 10 years old male Japanese child presented with recurrent episodes of headache, nausea and vomiting of 5 years duration and hyperlactic acidemia. These episodes were associated with motor weakness on the right side, with difficulties in language and memory and visual disturbance. Neurological examination revealed generalized muscle weakness with mild right sided hemiparesis. The Magnetic Resonance Imaging revealed infarct like lesions in the left occipital regions and the left medial temporal. The mitochondrial DNA mutations A3243G, T3271C and G13513A were tested using Polymerase Chain Reaction-Restriction Fragment Length  Polymorphism analysis and direct sequencing. The heteroplasmic A3243G mutation was detected in the blood of the patient and his mother. L-Arginine is reported to be beneficial for the patients and a preventive treatment was given in the form of arginine 500 mg twice per day.