Hyperuricosuric encephalopathy without hyperuricaemia

Abstract

A 3-year-old girl is described, presenting with the majority of the clinical manifestations found in the classical form of encephalopathy with hyper-uricaemia and hyperuricosuria. The clinical picture differed from the latter in the following ways: the patient was a girl, the parents were first cousins, and no other members of the family were affected. From the biochemical point of view, an increased urinary excretion of uric acid was observed, values varying from 35 to 45 mg./kg. daily. Uricaemia, however, was always normal. After intravenous administration of labelled glycine, specific activity was maximal at 120 hours with 72 counts per minute per mg. urinary uric acid, while the cumulative excretion after 7 days was 1.7% of the injected dose. It was concluded that the encephalopathy was due to a disturbance of the biosynthesis of purines, differing from the classical type. The disease is probably inherited as an autosomal recessive trait.