Background and goal of study: Acute kidney injury (AKI) is a frequent complication after orthotopic liver transplantation (OLT) and it`s early detection is of crucial importance for an appropriate management. Since the traditional kidney function parameters like serum-creatinine (s-Cr) have severe limitations concerning early detection of AKI, novel biomarkers such as TIMP-2 and IGFBP7, have been studied and shown to be superior in previous studies in critically ill patients. The aim of our study was to evaluate the predictive value of these novel biomarkers during the early perioperative period after human OLT. 
Materials and Methods: Paired urine and blood samples from patients undergoing OLT were collected at five different time points (TP): after induction of anesthesia (TP0), end of surgery (TP1) and at day 1 and 2 after OLT (TP2, TP3). The incidence of perioperative AKI was assessed according to the Acute Kidney Injury Network (AKIN) criteria. The detection of urinary TIMP-2 and IGFBP7 was performed using the NephroCheck (NC) test (Astute140®Meter), an ELISA based assay, which defines the risk score for AKI. Data are presented as mean ± standard deviation (SD). 
Results and Discussion: Forty liver transplant recipients were enrolled in this study. Sixteen (40%) patients developed AKI stage 2 or 3 within 48 h post OLT and 6 (15%) patients were supported with renal replacement therapy. There was no significant difference in the receiver operating characteristics curve analysis at TP0 and TP1 between the NC test and s-Cr in regard of development of AKI 2 or 3 within the first 48 hours post OLT. S-Cr at TP2 performed even better (AUC 0.83; CI 0.68-0.93; p=0.0001) than the NC test (AUC 0.51; CI 0.34-0.67; p=0.26). Only on day 2, both, s-Cr (AUC 0.90; CI 0.76-0.97; p=0.0001) and NC (AUC 0.70; CI 0.54-0.84; p=0.02) predicted AKI 2 and 3. 
Conclusions:  TIMP-2 and IGFBP7 are not superior to the traditional kidney function parameters in predicting development of perioperative AKI II and III in clinical setting of human OLT.

TIMP-2 and IGFBP7 as early biomarkers of acute kidney injury after orthotopic liver transplantation