Epidemiological and Microbiome Associations Between Klebsiella pneumoniae and Vancomycin-Resistant Enterococcus Colonization in Intensive Care Unit Patients

Abigail Collingwood; Freida Blostein; Anna M Seekatz; Christiane E Wobus; Robert J Woods; Betsy Foxman; Michael A Bachman

doi:10.1093/ofid/ofaa012

Epidemiological and Microbiome Associations Between Klebsiella pneumoniae and Vancomycin-Resistant Enterococcus Colonization in Intensive Care Unit Patients

Open Forum Infect Dis. 2020 Jan 12;7(1):ofaa012. doi: 10.1093/ofid/ofaa012. eCollection 2020 Jan.

Authors

Abigail Collingwood¹, Freida Blostein², Anna M Seekatz³, Christiane E Wobus⁴, Robert J Woods³, Betsy Foxman², Michael A Bachman¹

Affiliations

¹ Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA.
² University of Michigan School of Public Health, Ann Arbor, Michigan, USA.
³ Department of Internal Medicine, Division of Infectious Diseases, University of Michigan, Ann Arbor, Michigan, USA.
⁴ Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA.

Abstract

Background: Prior colonization by Klebsiella pneumoniae and vancomycin-resistant Enterococci (VRE) is associated with subsequent infection, particularly in intensive care unit (ICU) populations. Screening for VRE colonization, but not K. pneumoniae, is routinely performed in some health care systems. Identification of patient factors associated with K. pneumoniae colonization could enable infection prevention.

Methods: ICU patients were screened for VRE and K. pneumoniae by rectal swab culture over 2 time periods: July-October 2014 (n = 1209) and January-May 2016 (n = 1243). Patient demographics, baseline laboratory data, comorbidities, and outcomes were analyzed. 16S rRNA gene-based analysis was performed on a subset of patients (n = 248) to identify microbiota characteristics associated with VRE and K. pneumoniae colonization.

Results: K. pneumoniae colonization (17.3% of patients in the 2014 cohort, 7.3% in 2016) was significantly associated with VRE colonization in multivariable analysis (P = .03 in 2016; P = .08 in 2014). VRE colonization was associated with poor underlying health, whereas K. pneumoniae colonization was associated with advanced age. The most prevalent operational taxonomic units were Escherichia coli /Shigella spp., Klebsiella, and Enterococcus, consistent with high rates of detectable K. pneumoniae and VRE by culture. Microbial community structure in noncolonized patients was significantly different from those with VRE, K. pneumoniae, or both, attributable to differences in the relative abundance of Klebsiella and Enterococcus.

Conclusions: K. pneumoniae co-colonizes with VRE and is a predominant taxon in ICU patients, but colonization was not associated with significant comorbidities. Screening for K. pneumoniae and VRE simultaneously could be an efficient approach for novel infection prevention strategies.

Keywords: Klebsiella; colonization; infection; microbiome; vancomycin-resistant Enterococci.

Abstract

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