Biomarkers for AKI can be stratified into markers primarily reflecting glomerular filtration (i.e., serum cystatin C), glomerular integrity (i.e., albuminuria and proteinuria), tubular stress [i.e., insulin-like growth factor binding protein 7 (IGFBP-7)], tubular damage [i.e., neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1)], and intra-renal inflammation (i.e., interleukin-18) (108). Here, IGFBP7 is linked to acute kidney injury.