Hypouricemia, Familial Renal, Due To Tubular Hypersecretion

Probenecid and pyrazinamide are the drugs most widely used in the evaluation of the renal handling of urate. By application of these drugs, three types of tubular defects responsible for renal hypouricemia have been identified (De Vries and Sperling, 1979). They include presecretory, postsecretory, and combined urate reabsorption in the kidney (see 220150). A fourth type of renal hypouricemia was described by Shichiri et al. (1982), Dumont and Decaux (1983), and Sanz et al. (1983). In this type of hypouricemia, responses of renal urate clearance to probenecid or pyrazinamide are normal, sometimes even exaggerated, and the hypouricemia appears to be due to tubular hypersecretion. Nakajima et al. (1987) described the familial occurrence of this form. Two brothers had hypouricemia and their mother had serum urate levels in the low normal range. Data were not provided on the father. It is noteworthy that the proband was a 36-year-old carpenter with eunuchoidism and a 48,XXYY karyotype. His brother and mother had normal karyotypes.