Prognostic value of kidney involvement in COVID-19

Introduction: Acute kidney injury is a complication described in patients with SARS-CoV-2 infection that is around 0.5-7% of cases. Objective: evaluate the prognostic value of kidney involvement in patients hospitalized for COVID-19 disease. Methods: A prospective cohort of patients over 18 years with a diagnosis of COVID-19 disease in the period from May to October 2020 was analyzed. All were followed up until hospital discharge or death. Clinical and biochemical parameters, Charlson score, mortality and severity of COVID-19 disease were evaluated. Results: Four hundred twelve patients entered the study, 57% men and mean age 51 +/- 16 years. Twenty percent had a Charlson score >= 3, the incidence of acute kidney injury, defined as the increase in serum creatinine 0.3 mg / dl from baseline, was 5.5% (n = 23) and hospital mortality was 2.2% (n = 9). The bivariate and multivariate analysis showed that the male sex [OR= 0.32 (IC 0.12-0.82), p = 0.017], D-dimer> 500 ng/ml [OR= 3.68 (IC 1.23-10.96), p = 0.019], urinary protein/creatinine > 0.20 [OR= 2.43 (CI 1.03-5.74), p = 0.043], and AKI [OR= 10.53 (CI 2.99-37.09), p <0.0001] were predictors of severe COVID-19, defined as respiratory rate >30 x min, oxygen saturation <93% or PO2/FIO2 <300. The univariate analysis of mortality was associated with the development of severe COVID-19 [OR= 68.76 (CI 8.39-563.36), p <0.0001] and acute kidney injury [OR= 45.41 (CI 10.45-197.22), p <0.0001]. Conclusion: Renal involvement is associated with worse evolution and higher mortality in COVID-19. The assessment of renal function and proteinuria are accessible parameters that should be included as risk factors in the initial evaluation of these patients.