Renal impairment in patients admitted due to COVID-19 -- the experience of University Hospital No 1 in Bydgoszcz.

Introduction: COVID-19 is a prominently respiratory infection, with potential renal complications. Our objective was to describe the incidence of renal impairment and its influence on clinical outcome in patients admitted to University Hospital No 1 in Bydgoszcz due to COVID-19. Material and methods: In this single-center observational study we retrospectively identified patients with a positive test result for SARS-CoV-2 from either a nasopharyngeal or oropharyngeal swab PCR (n = 988) who were admitted to University Hospital No 1 in Bydgoszcz, Poland since April 1, 2020 to April 30, 2021. Details of the patients' demographics, diagnoses (based on ICD-10 codes), eGFR and clinical outcomes were obtained using a combination of a manual chart review of the electronic medical record from the hospital database. Results: Median baseline eGFR was 77,4 ml/min (IQR 51,6-93,7 ml/min) and minimal eGFR was 68,7 ml/min (IQR 39,9-90 ml/min), p < 0,05. We found significant differences in median baseline and minimal eGFR between patients discharged and deceased (80,8 vs. 55,4 ml/min and 73,7 vs. 33 ml/min, respectively, p < 0,001). Patients who died (12,5 %) were older, with more co-morbidities including CKD and AKI, and presented a significantly lower value of eGFR both at baseline and during hospital stay, as well as, more frequent and extensive deterioration of eGFR. Factors predisposing to in-hospital death were age, atrial fibrillation, heart failure, coronary artery disease, and among them AKI and CKD were strong negative prognostic parameters. Conclusions: Renal impairment on admission as well as during hospitalization among patients with SARS-CoV-2 infection is a risk factor of negative outcome. [ABSTRACT FROM AUTHOR]