[Exercise-induced acute renal failure associated with renal vasoconstriction].

Exercise-induced acute renal failure without rhabdomyolysis is not a rare condition. We experienced 6 cases (5 men and a woman) during last the 8 years. All cases complained of severe loin pain and nausea after mild to moderate exercises (for example, a track race in an athletic meeting). The elevation of serum and urinary myoglobin was undetected. In 4 of 5 patients with abdominal CT, renal patchy vasoconstriction (wedge-shaped low-density lesion) was observed. This was diagnosed as exercise-induced acute renal failure with loin pain (serum creatinine levels: 1.7-8.6 mg/dl). The renal function in 5 of the 6 cases normalized in about three weeks by fluid replacement therapy and hemodialysis support, which one patient received for 3 days. One patient required a long time for improvement of renal function and renal insufficiency persisted (serum creatinine 1.8 mg/dl). In 2 patients, the concentration of serum uric acid became very low after the recovery of renal function. These two patients were diagnosed as an isolated hyperuricosuric hypouricemia. More than half of the 6 patients had previously experienced the same episodes (loin pain and nausea) after exercise. Exercise-induced acute renal failure, probably due to renal patchy vasoconstriction, seems to be not a rare disease. The etiology of renal patchy vasoconstriction after exercises remains to be elucidated. The occurrence of acute renal failure must be taken into consideration when the youngster, especially with renal hypouricemia, complains of severe loin pain and nausea after exercise such as a track race.