HEMIDYSTONIA IMPROVED BY BACLOFEN AND PET SCAN FINDINGS IN A PATIENT WITH GLUTARIC ACIDURIA TYPE-I

Glutaric aciduria type I is an autosomal recessive metabolic disorder in the oxidative pathway of lysine, hydroxylysine, and tryptophan caus ed by a defect or decreased activity of the enzyme glutaryl coenzyme A dehydrogenase.(1) Since the first description by Goodman et al(2) in 1975, fewer than 20 cases of glutaric aciduria type I have been report ed. By 1 year of age, affected individuals generally have recurrent ep isodes of vomiting and lethargy associated with metabolic acidosis, wh ich is usually caused by a preexisting (nonprogressive) encephalopathi c substrate and is often triggered by infection. Progressive neurologi c deficits include dysarthria, dystonia, and choreoathetosis. Most aff ected children are also mentally retarded. The neurologic outcome does not appear to correlate with the acuteness of the presentation or wit h the degree of residual enzyme activity.(3) Deficiency of the enzyme glutaryl coenzyme A dehydrogenase is demonstrable in leukocytes, fibro blasts, and hepatocytes.(4) The present report describes two novel asp ects of glutaric aciduria type I. First, we describe the presence of h emidystonia, which has not been previously reported in glutaric acidur ia type I, and improvement of dystonia with baclofen treatment. Second , we provide the first description of glucose metabolic activity studi ed with position-emission tomography (PET) in this disorder.