LCN2 and acute kidney injury: Risk stratification by ACEF scores ≥ 1.1, followed by normalized NGAL, still provides more satisfactory risk discrimination (AUROC, 0.876; 95% CI, 0.800–0.953) than does normalized NGAL alone (AUROC, 0.754; 95% CI, 0.681–0.826) for the early detection of AKI.