Acute kidney injury in hospitalized patients due to COVID-19

The incidence of acute kidney injury (AKI) in hospitalized patients with coronavirus disease 2019 (COVID-19) is variable, being associated with worse outcomes. The objectives of the study were to evaluate the incidence, risk factors and impact of AKI in subjects hospitalized for COVID-19 in two third- level hospitals in Córdoba, Argentina.

A retrospective cohort study was conducted. 448 adults who were consecutively hospitalized for COVID-19 between March and the end of October 2020 at Hospital Privado Universitario de Córdoba and Hospital Raúl Angel Ferreyra were included. The incidence of AKI was 19% (n = 85). 50.6% presented AKI stage 1 (n=43), 20% stage 2 (n=17) and 29.4% stage 3 (n=25, of which 18 required renal replacement therapy). In the multivariate analysis, the variables that were independently associated with AKI were: age (adjusted Odd ratio -aOR- =1.30, 95%CI=1.04-1.63, p=0.022), history of chronic kidney disease (aOR=9.92, 95%CI=4.52-21.77, p<0.001), blood neutrophil count at admission (aOR=1.09, 95%CI=1.01-1.18, p=0.037) and requirement for mechanical ventilation (MV) (aOR=6.69, 95%CI=2.24-19.9, p=0.001). AKI was associated with longer hospitalization, greater admission and length of stay in the intensive care unit, a positive association with bacterial superinfection, sepsis, respiratory distress syndrome, MV requirement and mortality (mortality with AKI=47.1% vs without AKI=12.4%, p<0.001). AKI was independently associated with higher mortality (aOR=3.32, 95%CI=1.6-6.9, p=0.001).

In conclusion, the incidence of AKI in adults hospitalized for COVID-19 was 19% and had a clear impact on morbidity and mortality. Local predisposing factors for AKI were identified.