Hypouricemia, Hypercalciuria, and Decreased Bone Density: A Hereditary Syndrome

A 53-year-old man had hypouricemia (serum uric acid, 0.6 to 1.1 mg/100 ml), with an increased renal uric acid clearance (55 ml/min), idiopathic hypercalciuria (up to 460 mg/24 hr), and markedly decreased bone density. Uric acid clearance was suppressed by pyrazinamide to 40.4 ml/min and increased by probenecid to 75 ml/min. No other metabolic abnormalities were detected. A survey of the available members of the patient's family (23 in 3 generations) showed 4 additional similarly affected persons—a brother and a sister of the propositus and two of their grandchildren from a consanguineous marriage. The syndrome is transmitted as an autosomal recessive trait. None of these abnormalities could be detected in the obligate heterozygotes.