Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

ICU Acquisition Rate, Risk Factors, and Clinical Significance of Digestive Tract Colonization With Extended-Spectrum Beta-Lactamase–Producing Enterobacteriaceae: A Systematic Review and Meta-Analysis*

Detsis, Marios MD, MPH; Karanika, Styliani MD; Mylonakis, Eleftherios MD, PhD

doi: 10.1097/CCM.0000000000002253
Review Articles

Objective: To evaluate the acquisition rate, identify risk factors, and estimate the risk for subsequent infection, associated with the colonization of the digestive tract with extended-spectrum beta-lactamase–producing Enterobacteriaceae during ICU-hospitalization.

Data Sources: PubMed, EMBASE, and reference lists of all eligible articles.

Study Selection: Included studies provided data on ICU-acquired colonization with extended-spectrum beta-lactamase–producing Enterobacteriaceae in previously noncolonized and noninfected patients and used the double disk synergy test for extended-spectrum beta-lactamase–producing Enterobacteriaceae phenotypic confirmation. Studies reporting extended-spectrum beta-lactamase–producing Enterobacteriaceae outbreaks or data on pediatric population were excluded.

Data Extraction: Two authors independently assessed study eligibility and performed data extraction.

Data Synthesis: Thirteen studies (with 15,045 ICUs-patients) were evaluated using a random-effect model and a meta-regression analysis. The acquisition rate of digestive tract colonization during ICU stay was 7% (95% CI, 5–10) and it varies from 3% (95% CI, 2–4) and 4% (95% CI, 2–6) in the Americas and Europe to 21% (95% CI, 9–35) in the Western Pacific region. Previous hospitalization (risk ratio, 1.57 [95% CI, 1.07–2.31]) or antibiotic use (risk ratio, 1.65 [95% CI, 1.15–2.37]) and exposure to beta-lactams/beta-lactamase inhibitors (risk ratio, 1.78 [95% CI, 1.24–2.56]) and carbapenems (risk ratio, 2.13 [95% CI, 1.49–3.06]) during the ICU stay were independent risk factors for ICU-acquired colonization. Importantly, colonized patients were more likely to develop an extended-spectrum beta-lactamase–producing Enterobacteriaceae infection (risk ratio, 49.62 [95% CI, 20.42–120.58]). The sensitivity and specificity of prior colonization to predict subsequent extended-spectrum beta-lactamase–producing Enterobacteriaceae infection were 95.1% (95% CI, 54.7–99.7) and 89.2% (95% CI, 77.2–95.3), respectively.

Conclusions: The ICU acquisition rate of extended-spectrum beta-lactamase–producing Enterobacteriaceae ranged from 5% to 10%. Previous use of beta-lactam/beta-lactamase or carbapenems and recent hospitalization were independent risk factors for extended-spectrum beta-lactamase–producing Enterobacteriaceae colonization, and colonization was associated with significantly higher frequency of extended-spectrum beta-lactamase–producing Enterobacteriaceae subsequent infection and increased mortality.

All authors: Infectious Diseases Division, Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, RI

*See also p. 752.

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (

Drs. Detsis and Mylonakis accept full responsibility for the conduct of the study, have access to the data, and have control of the decision to publish. Drs. Detsis had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Drs. Detsis and Karanika conceptualized and designed the study, performed the literature search, participated in data collection, extraction and interpretation, prepared tables and figures, performed the statistical analysis, wrote and drafted the initial article, approved the final article as submitted and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Dr. Mylonakis conceptualized and designed the study, interpreted the data, reviewed and revised the article, approved the final article as submitted, and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

The authors have disclosed that they do not have any potential conflicts of interest.

For information regarding this article, E-mail:

Copyright © 2017 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved.