Mitochondrial NADH-coenzyme Q reductase deficiency in Leigh's disease.

A 4 1/2-month-old girl suffered from psychomotor retardation, generalized hypotonia, poor feeding, hyperreflexia, nystagmus, optical atrophy and choreoathetosis from the age of 3 months. Her blood lactate level was elevated to 40 mg/dL. Magnetic resonance imaging of her brain showed low T1 and high T2 signal intensities in the bilateral putamen, thalamus, red nuclei, substantia nigra, superior and inferior colliculi, cerebral peduncles and periaqueductal lesions. Muscle histochemistry and electron microscopic examinations were all normal except for variation in fiber size showing a myopathic change. An assay of muscle mitochondrial respiratory enzyme activities revealed a deficiency of NADH-coenzyme Q reductase. Molecular analysis did not reveal the putative T to G transversion at the nucleotide 8,993 of mitochondrial DNA in muscle biopsies. Leigh's disease was indicated by the clinical and radiologic manifestations. The patient died at 10 months of age from pneumonia and respiratory failure. There have been only sporadic reports of patients with Leigh's disease in Taiwan, and, to our knowledge, this is the first documented case of a Taiwanese patient with mitochondrial NADH-coenzyme Q reductase deficiency.