Rhabdomyolysis and acute renal failure

In order to determine the prevalence of rhabdomyolysis-associated acute renal failure (RM-ARF) and assess the effect of oliguria on biochemical features in this condition, 127 cases of ARF seen over 18 months were reviewed. Eleven cases of RM-ARF were seen, a prevalence of 8.6% of all cases of ARF. There were ten males and one female (age range 15-72 years) with precipitating events being trauma in three, coma in two, infection in two and other causes in five. Ten had concurrent clinical or historical evidence of dehydration, two had mild hypokalemia, and one abused alcohol. Serum and urine myoglobin by radioimmunoassay were greater than 800 ng/l in all cases tested. False negative tests for urine myoglobin by o-tolidine reaction after (NH4)2SO4 extraction occurred in four cases. Despite attempted forced saline diuresis and urinary alkalinisation, seven became oliguric and required dialysis for 12-81 days. Initially (pre-dialysis) oliguric patients had significantly higher maximum serum levels of potassium, phosphate, and rate of rise of creatinine, significantly lower trough levels of calcium, and no significant difference in peak creatine phosphokinase or uric acid levels than non-oliguric patients. Two subjects developed recovery phase hypercalcemia, four required fasciotomy for compartment syndromes, three sustained permanent nerve damage, and three required limb amputation. Ten survived, with a mean creatinine clearance of 96 ml/min after nine to 30 months. RM-ARF is common, may be clinically occult and show false negative urine myoglobin tests. Hyperkalemia, hyperphosphatemia, and hypocalcemia are more common in oliguric than in non-oliguric RM-ARF, but both have a good prognosis with appropriate medical and surgical management.