METABOLIC STROKE IN CARBAMYL-PHOSPHATE SYNTHETASE DEFICIENCY

Stroke-like episodes with hemiparesis have been described in children with different inherited metabolic diseases. We report the novel obser vation of a severe stroke as the presenting sign in an 18-month-old gi rl with carbamyl phosphate synthetase (CPS) deficiency. MRI revealed i nfarction within the territory of the right middle cerebral artery. Lo calized H-1-NMR spectroscopy showed elevation of glutamine (at 2.0-2.5 and 3.7 ppm) and lactate within the region of infarction. CPS activit y in the liver was reduced (2.5 mU/mg protein, n = 12-35). On a protei n-restricted diet including arginine supplementation, the child has de veloped well with moderate mental retardation: no neurologic relapses have been observed over a period of 4 years, CPS deficiency has to be added to the list of metabolic diseases that may lead to stroke-like e pisodes. In every case of unclear hemiparesis in childhood, urea cycle defects should be included in the differential diagnosis.