Does the kidney injury molecule-1 predict cisplatin-induced kidney injury in early stage?

Background It is not possible to diagnose acute kidney injury (AKI) in early stages with traditional biomarkers. Kidney injury molecule-1 (KIM-1) is a novel biomarker promising the diagnosis of AKI in early stages. We studied whether urinary and serum KIM-1 (KIM-1(U) and KIM-1(S)) concentrations were useful in predicting cisplatin-induced AKI in early stages. Methods We prospectively analysed 22 patients on cisplatin treatment. KIM-1(S) and KIM-1(U) concentrations were assessed in the samples of the patients on four different time periods (before treatment [BT], first [AT(1)], third [AT(3)] and fifth [AT(5)] day after treatment). Results KIM-1(U) concentrations on the first day after cisplatin treatment in patients with AKI were significantly increased compared to both KIM-1(U) concentrations of the same patients BT (P=0.009) and to AT(1)-KIM-1(U) concentrations of the patients without AKI (P=0.008). A receiver operating characteristic analysis revealed that AT(1)-KIM-1(U) concentrations may predict AKI with an 87.5% sensitivity and 93.3% specificity (area under the curve=0.94). KIM-1(S) concentrations were not significantly changed between BT and AT periods. Conclusions KIM-1(U) concentrations may predict cisplatin-induced AKI in early stages with high sensitivity and specificity.