The ratio of plasma neutrophil gelatinase-associated lipocalin predicts acute kidney injury in patients undergoing liver transplantation

Background: Postoperative acute kidney injury (AKI) is associated with high morbidity and mortality after liver transplantation (OLT). Previous studies have shown the value of plasma neutrophil gelatinase-associated lipocalin (NGAL) taken 2 hours after reperfusion of the liver graft as an early marker predicting AKI. The study was performed to determine whether plasma NGAL concentrations obtained as early as 1 hour after reperfusion was predictive of AKI and whether the NGAL ratio was an early predictor for AKI in the first 48 hours after OLT. Methods: Twenty-six liver transplant recipients donated plasma samples for NGAL determinations at induction (T1), at graft reperfusion (T3) as well as after 1 (T4) and hours 2 (T5), and at the end of the surgery (T7). AKI was defined at 48 hours after liver transplantation according to the acute kidney injury network criteria. Predictive ability was assessed using areas under the curve of receiver operator characteristic analyses. Results: The area under the curve of the receiver operator characteristics curve of (plasma NGAL concentration at T4)/(plasma NGAL concentration at T1) to predict AKI was 0.717 at T5, 0.765 at T7, 0.714 at T8 (24 hours post-OLT), and 0.781 at T9 (48 hours post-OLT). Conclusion: The plasma NGAL concentrations taken 1 hour after reperfusion of the liver graft seem to be predictive of AKI; the NGAL changing ratio may be an early predictor for AKI in the first 48 hours after OLT.