TIMP2 and acute kidney injury: Other than the urine indicators, such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury (KIM1), liver-type fatty-acid-binding protein (L-FABP), insulin-like growth factor-binding protein-7 (IGFBP-7), and tissue inhibitor of metalloproteinase-2 (TIMP2), plasma biomarkers deserve exploration due to their continued participation in the inflammatory response during AKI development and disease prognosis (14).