Primary overproduction of urate caused by a partial deficiency of hypoxanthine-guanine phosphoribosyl transferase.

Inherited enzyme deficiencies are found in a small proportion of patients with gout who produce an excess of uric acid. The clinical, biochemical and therapeutic aspects of a case of hyperuricaemia caused by an atypical mutant hypoxanthine-guanine phosphoribosyl transferase are presented. Urate overproduction was moderate and controlled by allopurinol therapy.