Among the most commonly used are: neutrophil gelatinase-associated lipocalin (NGAL), which is almost undetectable in normal epithelial renal cells and its expression is induced during AKI [18], [19]; kidney injury molecule type 1 (Kim-1), which is induced on the surface of proximal tubule cells during ischemic or nephrotoxic injury [20]–[22]; and interleukin 18 (IL-18), which is over-expressed in patients diagnosed with AKI [23], [24]. Here, LCN2 is linked to acute kidney injury.