Normal activity of metabolic pathways involved in the formation and utilization of phosphoribosylpyrophosphate in erythrocytes of patients with primary metabolic gout

The activity of metabolic pathways involved in the formation and utilization of phosphoribosylpyrophosphate (PRPP) was studied in the erythrocytes of 34 patients with idiopathic metabolic gout. The activities of the oxidative pentose shunt, of the hypoxanthine guanine and adenine phosphoribosyltransferases (HGPRT, APRT) and of PRPP synthetase, as well as the rates of PRPP generation and of adenine incorporation into nucleotides were found to be normal in the erythrocytes of all these patients. Four patients with metabolic gout due to enzymatic abnormalities, two relatives with partial deficiency of HGPRT and two relatives with mutant feedback resistant PRPP synthetase, were studied for comparison. The significance of the results is discussed in relation to postulated mechanisms for purine overproduction in metabolic gout.