Importance of neutrophil gelatinase-associated lipocalin and cystatin C in early diagnosis of cardiopulmonary bypass associated acute kidney injury in adult patients

Aim: The development of acute kidney injury (AKI) after cardiopulmonary bypass (CPB) is associated with increased rates of mortality and morbidity. The identification of reliable biomarkers that allow earlier diagnosis of AKI in the post-operative period may increase the success of therapeutic interventions. The aim of our present study was to measure neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (Cys C) levels and to test the accuracy and reliability as an early biomarker. Material and Methods: The study was designed as a prospective observational study, comparing creatinine, NGAL, and Cys C levels in patients who develop AKI or not after heart surgery using CPB. Forty-three patients met the inclusion criteria. We obtained blood samples for NGAL and Cys C at two predetermined time-points (6 and 24 hours) after the initiation of CPB. Results: According to the AKIN classification, 8 patients (44%) developed AKI (AKI1 groups) and 35 (56%) did not (non-AKI). The areas under the receiver operating characteristic curve (AUCROC) values were calculated for all parameters. AUCROC value was 0.81 (95% CI: 0, 63 to 1, 00) for 6th hours NGAL and 0.867 (95% CI: 0, 00-1, 00, p: 0.004) for 24th Cys C. Therefore, NGAL measured in 6th hours and 24th Cys C, have diagnostic value for early diagnosis of acute kidney injury. Conclusion: Based on our study, NGAL levels measured in 6th hour, and Cys C levels measured in the 24th hour have high predictive value for early diagnosis for CPB-ABH