Cystatin C and Neutrophil Gelatin-associated Lipocalin (NGAL) Can Predict Acute Kidney Injury and In-Hospital Mortality in COVID-19 Patients

Background: Prediction and early diagnosis of acute kidney injury (AKI) in critically ill Coronavirus disease 2019 (COVID-19) patients are of great importance. Therefore, using promising renal biomarkers such as cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) to identify the risk of future AKI is crucial. Materials and Methods: A total of 89 adult patients with COVID-19 were included in this study. Serum cystatin C and NGAL concentration were assessed on intensive care unit (ICU) admission then repeated after 48 hours. Serum creatinine was followed for 7 days to report the development of AKI. Results: Among the COVID-19 patients, 28.1% developed AKI. Although admission serum creatinine was not significantly different between the AKI group and the non-AKI group (p=0.375), admission Cystatin C (p=0.018), and NGAL (p<0.001) were significantly different between both groups. After 48 hours, a change in Cystatin C level (p<0.001) but not NGAL (p=0.4) was a predictor for AKI. Logistic regression model including age (p=0.031), Cystatin C on 48 hrs (p=0.003) and NGAL on admission (p=0.015) could predict AKI in COVID-19 patients. Conclusion: Serum Cystatin C and NGAL in ICU could be used to predict AKI in COVID-19 patients. A logistic regression model including age, Cystatin C on 48hrs, and NGAL on admission might be a tool for individualized risk estimation of AKI in COVID-19 patients.