Clinical studies indicate that urinary neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), interleukin 18 (IL-18) and liver-type fatty acid binding protein (L-FABP) all predict AKI in children following cardiopulmonary bypass prior to changes in serum creatinine [19-21]. Here, LCN2 is linked to acute kidney injury.