Urinary MMP-7 levels peaked within 6 h, and urinary MMP-7 had AUCs of 0.81 (children) and 0.76 (adults) in patients developing severe AKI, outperforming a clinical model and urinary biomarkers (NGAL, IL-18, and [TIMP-2] x [IGFBP-7]). The gene discussed is LCN2; the disease is acute kidney injury.