The Clinical Significance of Hypouricemia

Hypouricemia (serum urate, < 2 mg/100 ml) was noted in 0.97% of 6629 consecutive serum urate measurements done at two large hospitals. In two thirds of the hypouricemic patients drugs, including aspirin, allopurinol, X-ray contrast agents, and glyceryl guaiacholate, seemed to be responsible for the decreased serum urate concentration; disseminated carcinomas were noted in nine more hypouricemic patients. In many of these subjects an alteration in the renal tubular handling of uric acid seemed to cause the development of hypouricemia. Poor dietary intake of protein and purines and hypo-osmolality were common findings that may have contributed to the development of hypouricemia in some patients. Although hypouricemia has been reported as a common manifestation of several relatively rare diseases, these illnesses are unusual causes of the hypouricemia found in a general hospital population.