Community-acquired acute kidney injury in Southeast Brazil and independent risk predictors: a prospective cohort study

The prevalence and risk factors for community-acquired acute kidney injury (CA-AKI) are unknown. This study aimed to explore the incidence of CA-AKI in a tertiary care center and to depict the main clinical characteristics related to this condition.

This was a prospective cohort study involving patients admitted to the emergency department (Hospital de Clínicas, UNICAMP, Campinas, Brazil) between January 2019 and September 2021. Adults (≥ 18 yrs) who presented to the emergency room with symptoms potentially associated with an increased risk of AKI were included. Individuals with a prior diagnosis of stage 5 chronic kidney disease or with a confirmed COVID-19 infection were excluded. A score based on clinical signs and symptoms was assigned to predict the risk of severe AKI.

Of the 261 patients enrolled, CA-AKI was diagnosed in 65 (25%). The CA-AKI group was older [57(± 14) vs. 51(± 18) years, p = 0.02] and had a lower baseline estimated glomerular filtration rate [103 (88–113) vs. 109 (97–121) mL/min/1.73 m²; p = 0.01]. Logistic regression showed that scores ≥ 7 points [odds ratio (OR) 2.8 (1.281–6.133), 95% confidence interval (CI), p = 0.01], age [OR 1.02 (1.007–1.044), 95% CI, p = 0.008] and liver disease [OR 2.6 (1.063–6.379), 95% CI, p = 0.03] were independently related to CA-AKI.

The incidence of CA-AKI was not negligible among patients admitted to a tertiary care center; CA-AKI can be suspected on a clinical basis and confirmed by serum creatinine. Age, liver disease and higher scores in risk prediction tools were related to an increased incidence of CA-AKI.