TIMP2 and acute kidney injury: To address this challenge, several AKI biomarkers, including NGAL [10], KIM-1 [11], IL-18 [12], L-FABP [13], and TIMP-2*IGFBP-7 [14,15] have been identified as predictors of the onset of AKI, the severity of AKI, and renal prognosis of AKI in critically ill patients.