Rhabdomyolysis: a 10-year retrospective study of patients treated in a medical department.

Background: Rhabdomyolysis is a common and potentially life-threatening syndrome, and acute kidney injury (AKI) is a serious complication. We performed a 10-year retrospective study that included all patients treated for rhabdomyolysis in a medical clinic. We examined the relationships between the levels of creatine kinase (CK), myoglobin, and creatinine (as a marker of renal function and thereby AKI), and whether the myoglobin/CK ratio could be a valuable tool in the clinical evaluation of this patient group. Clinical characteristics were noted.

Methods: The study included all patients treated for rhabdomyolysis in the Department of Medicine, Oslo University Hospital Ulleval, from 2003 to 2012. Rhabdomyolysis was defined as a serum CK activity more than five times the upper reference limit.

Results: A total of 341 patients were included in the study; 51% developed AKI, and 20% of those required dialysis. Logistic regression showed that myoglobin concentration [P < 0.001, odds ratio (OR) = 6.24] was a better predictor than CK activity (P = 0.001, OR = 3.45) of the development of AKI. The myoglobin/CK ratio was a good predictor of AKI (P < 0.001, OR = 5.97). The risk of developing AKI increased with increasing myoglobin/CK ratio (P < 0.001); a ratio more than 0.2 was associated with an increased likelihood of developing AKI.

Conclusions: Serum myoglobin concentration was a better predictor of AKI than was serum CK activity. The myoglobin/CK ratio may be useful for assessing the likelihood of developing AKI.