A case of uric acid renal stone with hypouricemia caused by tubular reabsorptive defect of uric acid.

A 60-year-old man had a uric acid stone in the kidney and laboratory findings of hypouricemia (1.1 mg. per 100 ml.) and increased uric acid clearance (43 ml. per minute per 1.73 m.2). Clearance of uric acid exceeded the endogenous creatinine clearance after administration of pyrazinamide, an inhibitor of renal tubular secretion of uric acid. It was suggested that our patient had a complete defective mechanism for uric acid reabsorption, resulting in hyperuricuria and the formation of the uric acid stone.