Numerous studies have demonstrated that PENK can detect AKI with sensitivity comparable to or superior to that of other established biomarkers, such as Neutrophil gelatinase-associated lipocalin (NGAL) and Tissue inhibitor of metalloproteinases 2 (TIMP-2) × Insulin-like growth factor-binding protein 7 (IGFBP-7). This evidence concerns the gene IGFBP7 and acute kidney injury.