How Does Rhabdomyolysis Cause Renal Failure?
Untreated, rhabdomyolysis often leads to acute renal failure secondary to acute tubular necrosis(ATN). Myoglobin itself is not thought to be a toxin. However, when large amounts of myoglobin are excreted in acidic urine, myoglobin dissociates into two components — globin and ferrihemate. Ferrihemate is currently suspected to be the toxic component of myoglobin that results in renal injury. Tubular obstruction by myoglobin probably plays a secondary role in rhabdomyolysis induced renal failure. While we are not able to predict with certainty which patients with rhabdomyolysis will develop ATN, the amount of elevation in CPK, K+, and PO4- are thought to have some degree of positive predictive value.
