ABSTRACT
Introduction. Coronavirus Disease 2019 (COVID-19) can present pulmonary and extra pulmonary manifestations. One of the common complications caused by the disease is acute kidney injury (AKI). This study aims to assess the prevalence of kidney dysfunction in COVID-19 in-patients and its relationship to the outcomes of hospitalization in COVID-19 patients of a tertiary teaching hospital in Mashhad, Iran. Methods. A consecutive cohort study was carried out on patients' record extracted from hospital information system (HIS system) admitted in a tertiary teaching hospital following a major outbreak in Mashhad in 2020. Serum creatinine concentration and other laboratory parameters were extracted from HIS system. Incidence rate for acute kidney injury (AKI) according KDGO criteria was examined during the study. Outcomes, including mortality, and hospital length of stay was analyzed. Results. We included 715 COVID-19 patients that135 (21.3%) of whom died in the hospital and 488(77.3%) of studied patients have recovered. The mean age of the patients was 59.45 .. 16.83 years old, including 452 males (63.3%) patients. The mortality rate was higher for men compared to women (P = 0.005). The greatest change in mean creatinine was observed between first day of hospitalization (1.31 .. 1.33) and second day of hospitalization (1.81 .. 1.95). During the study period, AKI occurred in 17.84% of patients. The greatest percentage of AKI was observed on the 2nd and 7th days of hospitalization, which were 27.1% and 24.3%, respectively. This study demonstrated that patients with elevated creatinine and kidney impairment had higher risk of mortality (P < 0.0001). Mortality status had a direct and significant correlation with age, CRP, Urea and albumin in serum during hospitalization(P < 0.05). However, length of hospitalization was not associated with AKI (P = 0.465). Conclusion. There was a great prevalence of kidney impairment in hospitalized COVID-19 patients. After adjustment for confounders, kidney impairment indicators were associated with higher risk of in hospital death. Therefore, it is critical that clinicians consider serum factors indicating kidney impairment in hospitalized COVID-19 patients.