Value of joint detection of multiple biomarkers on early diagnosis of acute kidney injury in critical patients

Objective To assess the value of joint detection of serum cysteine proteinase inhibitors C (sCys-C), urinary kidney injury molecule 1 (uKIM-1), urinary neutrophil gelatinase-associated lipocalin(uNGAL) and urinary interleukin 18 (uIL-18) for early diagnosis of acute kidney injury (AKI) in critically ill patients. Methods A total of 256 adult patients who stayed Intensive Care Unit for 24 hours in the Third People's Hospital of Liaocheng between Aug 2011 and Dec 2012 were enrolled. According to Kidney Injury Net(AKIN) work, the patients were divided into non-AKI group and AKI group (including state 1, 2 and 3). The concentrations of urine NGAL, KIM-1, IL-18 and serum sCys-C were measured. The diagnosis value of four biomarkers joint detection and single detection for AKI were analyzed with the receiver operating characteristic (ROC) curve and the area under curve (AUC). Results (1) The levels of uNGAL, uKIM-1, uIL-18 and sCys-C were higher in patients with AKI than the patients with no AKI (P﹤0.01). (2) The area under curves of uNGAL, uKIM-1, uIL-18, sCys-C and joint detection were 0.742, 0.871, 0.803, 0.703, 0.925 respectively. (3) The sensitivity and specificity of parallel tests and serial tests of four biomarkers were 97.9%, 62.8%, 64.3% and 96.2% respectively. There were significant differences of sensitivity or specificity between single test and joint tests. Conclusions The urine NGAL, KIM-1, IL-18 and serum Cys-C are sensitive indexes for the early diagnosis of acute kidney injury. Joint detection has high value for early diagnosis of AKI.