Recently, two novel urinary biomarkers, tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7), were validated for predicting moderate-to-severe acute kidney injury (AKI) (stages 2 and 3 by Kidney Disease Improving Global Outcome (KDIGO) [1] criteria) in critically ill patients [2, 3]. This evidence concerns the gene TIMP2 and acute kidney injury.