[Mitochondrial encephalomyopathy. Report of a case].

A typical case of mitochondrial encephalomyopathy with lactic acidemia and stroke-like episodes (MELAS) was reported. The main clinical manifestations consisted of short stature, psychomotor deterioration, sensorineural deafness, and hemiparesis. The laboratory findings disclosed abnormal lactic acid tolerance abnormal EEG, VEP, AEP, SEP, and MCV. The CT scan showed multiple intracerebral infarcts, basal ganglia calcifications, and cerebral atrophy. A muscle biopsy was performed. The frozen sections with modified gomori trichrome stain revealed ragged-red-fiber which reacted strongly positive in NADH-TR stain. The electron microscopy revealed subsarcolemmal aggregation of mitochondria of various sizes with paracrystalline inclusions, abnormally arranged cristae, and osmiophilic dense-bodies in their matrices.