Acute renal failure after exercise in a child with renal hypouricemia

We describe a 15 year old boy with renal hypouricemia who developed acute renal failure after a school athletics meeting, accompanied by appendicitis. During acute renal failure, the highest level of uric acid was 5.0 mg/dL, creatinine 7.9 mg/dL and urea nitrogen 58.6 mg/dL. After recovery, the serum uric acid fell to 0.9 mg/dL and the fractional excretion of uric acid (FEu_A) exceeded the normal range. The probenecid and pyrazinamide tests showed that the patient had a total defect of uric acid reabsorption. This case suggested that strenuous exercise could be responsible for acute renal failure in patients with renal hypouricemia.