Urate metabolism in primary hyperparathyroidism.

Urate metabolism was studied in 40 patients with primary hyperparathyroidism (HPT), 20 of them had a history of renal stones. Preoperatively they had, compared to controls, a reduction of the clearance of urate and a rise of the serum urate concentrations. These disturbances were normalized postoperatively. HPT patients, in particular those with a history of stones, had a high urinary calcium excretion probably as a result of both increased bone resorption and intestinal calcium uptake. There was a close relationship between the urinary urate and calcium excretions preoperatively but not after surgery. There were no consistent differences with regard to urate metabolism in the stone-forming individuals with HPT as compared to those who had never formed a renal stone and thus it seems unlikely that disturbances of urate handling are of any particular importance for the well-known propensity to form stones in primary HPT.