Serum Neutrophil Gelatinase-Associated Lipocalin versus Serum Creatinine for the Prediction of Acute Kidney Injury after Liver Transplantation

Background: Acute kidney injury (AKI) is a common complication after liver transplantation (LT), and considerably increases the morbidity and mortality of the procedure. The gold standard of measuring the kidney function, the serum creatinine level (sCr), has poor specificity and sensitivity for the early diagnosis of AKI. Novel biomarkers for the prediction or early diagnosis of AKI, would potentially increase the opportunities for therapeutic interventions. Objective: To compare the diagnostic value of the standard renal marker, sCr and neutrophil gelatinase-associated lipocalin (NGAL) to predict AKI within 48 hours of LT. Methods: During a 9-month period from 2010 to 2011, NGAL was measured two times in 90 patients who underwent LT from deceased donors—after induction of anesthesia (NGAL1) and 2 hours after reperfusion of the liver graft (NGAL2). Patients were grouped according to the presence of risk factors for developing AKI according to the Acute Kidney Injury Network criteria (increase of ≥0.3 mg/dL in plasma creatinine above the baseline value within 48 hours). Results: 60 men and 30 women with mean±SD age of 40.2±14.2 years were included in this study. The incidence of AKI was 34% (95% CI: 24%–44%). The difference between the NGAL1 and NGAL2 (ΔNGAL) and the baseline NGAL concentration was predictive of AKI in all patients. Receiver operating characteristic (ROC) curve and area under curves (AUCs) of ΔNGAL and sCr levels during the first 48 hours of LT were similar in predicting AKI. The AUCs of the ΔNGAL to predict AKI was 0.64 (95% CI: 0.52–0.76). The development of AKI was significantly correlated with the number of units of fresh frozen plasma transfused intra-operatively (p=0.017) and cold ischemic time (p=0.042). Conclusion: Serum NGAL concentrations obtained during surgery is a predictor of AKI in patients undergoing LT.