Studies have shown that urinary biomarkers like neutrophil gelatinase-associated lipocalin (NGAL) [18–22], and recently the panel tissue inhibitor of metalloproteinases 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) [21, 23, 24], can detect AKI in critically ill patients earlier than SCr or UO, even when using the most sensitive KDIGO criteria. This evidence concerns the gene TIMP2 and acute kidney injury.