Assessment of the diagnostic ability of RIFLE and SOFA scoring systems in comparison with protein biomarkers in acute kidney injury

Background We aimed to assess the diagnostic sensitivity of Risk, Injury, Failure, Loss, and End-stage (RIFLE) and Sequential Organ Failure Assessment (SOFA) scoring systems regarding the serum creatinine level in acute kidney injury (AKI) patients hospitalized in the intensive care unit (ICU). This study also aims to compare the sensitivity of these scoring systems with that of mitochondrial pyruvate carrier 1 (MPC-1), interleukin-10 (IL-10) and neutrophil gelatinase-associated lipocalin (NGAL) as biomarkers. Methods This is a cross-sectional study. Thirty patients with increased creatinine level and decreased urine output were recognized as AKI patients, and 30 patients were selected as the control group. The serum levels of each of the proteins of interest were measured at the initial state (moment of entrance) and final state (14(th) day in the ICU). Statistical analysis was performed with respect to t-test, and a p-value < 0.05 was considered significant. The diagnostic ability of biomarkers was assessed using receiver operating characteristic (ROC) curve. Results The majority of patients were recognized in the risk level of RIFLE, and level 1 of SOFA scoring system. There was no correlation between RIFLE and SOFA (p = 0.123). The expression of MPC-1, IL-10 and NGAL was more remarkable compared with the serum creatinine level. The ROC area change for MPC-1 and IL-10 was higher compared with that for NGAL. As a result, MPC-1 and IL-10 are more reliable biomarkers than NGAL to predict the incidence of AKI in the earlier stage. Conclusions There was no significant correlation between SOFA and RIFLE classification, and also the sensitivity of these scoring systems was identified at the risk level for AKI patients. Instead, the level of biomarkers alters earlier, and in higher concentration, than creatinine and urine output changes; therefore, they are more reliable than RIFLE and SOFA scoring systems for prognosis purposes.