Epidemiological and Microbiome Associations Between and Vancomycin-Resistant Colonization in Intensive Care Unit Patients.

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

Methods: ICU patients were screened for VRE and 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 colonization.

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

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