Acute Tubular Necrosis Caused by Exercise-Induced Myoglobinuria

Reports of acute tubular necrosis after exercise-induced myoglobinuria are rare, especially among nonmilitary populations. A 19-year old university student developed acute tubular necrosis after an intramural wrestling match. Severe myalgia, elevated serum levels of creatine phosphokinase, and a positive o-tolidine test on urine suggested myoglobinuria, although gross pigmenturia was not present. Myoglobin was identified in his urine and serum by immunodiffusion and electrophoresis techniques. The course of this patient's renal failure was typical, except for a disproportionate rise in serum creatinine relative to blood urea nitrogen. A similar disproportion was seen in three other cases in which acute renal failure caused by rhabdomyolysis was present. Exercise-induced myoglobinuria is probably an underdiagnosed condition. The fact that it may produce life-threatening acute tubular necrosis should be kept in mind by physicians involved in the care of athletes and military personnel.