LCN2 and acute kidney injury: The peak plasma NGAL showed fair discriminatory power for prediction of AKI progression (AUC = 0.71, 95 % CI: 0.55–0.88) and need for RRT (AUC = 0.78, 95 % CI: 0.61–0.95), while urine NGAL performed less well for prediction of AKI progression (AUC = 0.70, 95 % CI: 0.58–0.81) and need for RRT (AUC = 0.70, 95 % CI: 0.58–0.82), and peak urine NGAL (≥230 ng/mg creatinine) predicted AKI progression with a sensitivity of 0.78 and specificity of 0.81, which was better than compared with septic AKI (AUC = 0.82 vs. 0.59, respectively; P = 0.04).