Risk-factor analysis for extended-spectrum beta-lactamase–producing Enterobacterales colonization or infection: Evaluation of a novel approach to assess local prevalence as a risk factor

Abstract

AbstractObjective:To explore an approach to identify the risk of local prevalence of extended-spectrum β-lactamase–producing Enterobacterales (ESBL-E) on ESBL-E colonization or infection and to reassess known risk factors.Design:Case–control study.Setting:Johns Hopkins Health System emergency departments (EDs) in the Baltimore–Washington, DC, region.Patients:Patients aged ≥18 years with a culture growing Enterobacterales between April 2019 and December 2021. Cases had a culture growing an ESBL-E.Methods:Addresses were linked to Census Block Groups and placed into communities using a clustering algorithm. Prevalence in each community was estimated using the proportion of ESBL-E among Enterobacterales isolates. Logistic regression was used to determine risk factors for ESBL-E colonization or infection.Results:ESBL-E were detected in 1,167 of 11,224 patients (10.4%). Risk factors included a history of ESBL-E in the prior 6 months (aOR, 20.67; 95% CI, 13.71–31.18), exposure to a skilled nursing or long-term care facility (aOR, 1.64; 95% CI, 1.37–1.96), exposure to a third-generation cephalosporin (aOR, 1.79; 95% CI, 1.46–2.19), exposure to a carbapenem (aOR, 2.31; 95% CI, 1.68–3.18), or exposure to a trimethoprim-sulfamethoxazole (aOR, 1.54; 95% CI, 1.06–2.25) within the prior 6 months. Patients were at lower risk if their community had a prevalence <25th percentile in the prior 3 months (aOR, 0.83; 95% CI, 0.71–0.98), 6 months (aOR, 0.83; 95% CI, 0.71–0.98), or 12 months (aOR, 0.81; 95% CI, 0.68–0.95). There was no association between being in a community in the >75th percentile and the outcome.Conclusions:This method of defining the local prevalence of ESBL-E may partially capture differences in the likelihood of a patient having an ESBL-E.