Acute kidney injury due to rhabdomyolysis

Abstract

Rhabdomyolysis is a clinical and biochemical syndrome that occurs when skeletal muscle cells disrupt and release creatine phosphokinase (CK), lactate dehydrogenase (LDH), and myoglobin into the interstitial space and plasma. The main causes of rhabdomyolysis include direct muscular injury, strenuous exercise, drugs, toxins, infections, hyperthermia, seizures, meta-bolic and/or electrolyte abnormalities, and endocrinopathies. Acute kidney injury (AKI) occurs in 33-50% of patients with rhabdomyolysis. The main pathophysiological mechanisms of renal injury are renal vasoconstriction, intraluminal cast formation, and direct myoglobin toxicity. Rhabdo-myolysis can be asymptomatic, present with mild symptoms such as elevation of muscular en-zymes, or manifest as a severe syndrome with AKI and high mortality. Serum CK five times higher than the normal value usually confirms rhabdomyolysis. Early diagnosis and saline volume expansion may reduce the risk of AKI. Further studies are necessary to establish the importance of bicarbonate and mannitol in the prevention of AKI due to rhabdomyolysis.