Quantifying risk of disease due to extended-spectrum β-lactamase producing Enterobacteriaceae in patients who are colonized at ICU admission

Abstract

BackgroundThe prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) has globally increased and spread to the community. No clinical score is available to select carriers in whom these organisms can be empirically targeted at ICU admission. MethodsWe prospectively assessed between 2009 and 2017 the prevalence of ESBL-PE infection in carriers at ICU admission. A logistic regression was used to determine independent risk factors associated with ESBL-PE infection, and to build a clinical risk score. ResultsOf the 8,061 admissions over the study 7-year period, 745 (9%) patients were ESBL-PE carriers at admission, of whom 395 had infections at ICU admission including 59 (15%) who had culture-proven ESBL-PE related infection. By multivariable analysis, age >60 years, cirrhosis, being on broad-spectrum antibiotics within the past three months, urinary or intra-abdominal source of infection, and the absence of chronic pulmonary disease, were the five independent factors associated with ESBL-PE infection in carriers. A clinical risk score ranging from 0 to 7 was built based on these variables, with an area under the receiver operating characteristic curve (ROC) of 0.82 (95% CI 0.78–0.86); p <0.001. The prevalence of ESBL-PE infection for clinical risk scores of 0–1, 2–3, 4–5, or 6–7 was 0%, 4%, 26%, and 49%, respectively. The negative predictive value when Mondor ESBL risk score is <4 was 97%. ConclusionESBL-PE related infection was not common in carriers at ICU admission. A clinical risk score may spare ESBL-PE carriers with lower risk of ESBL-PE infection at ICU admission unnecessary empiric carbapenem therapy.