LCN2 and acute kidney injury: However, another unique protein has been identified, FtL 25 (ferritin‐25), which may be associated with the prevention of AKI.[90] In another prospective nested case‐control study (N = 250),[91] the continuous urinary proteome of 22 AKI patients and 22 non‐AKI patients before, during, and after cardiopulmonary bypass (CPB) surgery were compared, and three new biomarkers for kidney function after cardiac surgery were identified: NGAL, hepcidin 25, and alpha‐1 microglobulin (α1MG).