Currently, the most promising early non-invasive biomarkers of AKI are serum and urinary neutrophil gelatinase-associated lipocalin (NGAL) [41], urinary interleukin-18 (IL-18) [42], kidney injury molecule-1 (KIM-1) [43, 44], and serum cystatin C [40]. This evidence concerns the gene LCN2 and acute kidney injury.