Population dynamics in colonizing vancomycin-resistant Enterococcus faecium isolated from immunosuppressed patients

TY - JOUR

T1 - Population dynamics in colonizing vancomycin-resistant Enterococcus faecium isolated from immunosuppressed patients

AU - Both, Anna

AU - Kruse, Florian

AU - Mirwald, Nadine

AU - Franke, Gefion

AU - Christner, Martin

AU - Huang, Jiabin

AU - Hansen, Jan Lennart

AU - Kröger, Nicolaus

AU - Berneking, Laura

AU - Lellek, Heinrich

AU - Aepfelbacher, Martin

AU - Rohde, Holger

N1 - Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.

PY - 2022/3

Y1 - 2022/3

N2 - OBJECTIVES: Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis (VRE) are a common cause of healthcare-associated infections. Whole genome sequencing-based typing methods yield the highest discriminatory power for outbreak surveillance in the hospital. We analysed the clonal composition of enteric VRE populations of at-risk patients over several weeks to characterise VRE population diversity and dynamics.METHODS: Five bone marrow transplant recipients (three colonised with vanA-positive isolates, two colonised with vanB-positive isolates) contributed three rectal swabs over a course of several weeks. Fourteen VRE colonies per swab were analysed by core genome multi locus sequence typing (cgMLST) and typing of the van-element.RESULTS: VRE populations were clonally diverse in three of five patients, and population composition changed dynamically over the time of observation. Besides new acquisition of VRE isolates, shared van-elements localised on nearly identical plasmids between clonally different isolates indicate horizontal gene transfer as a mechanism behind VRE population diversity within single patients.CONCLUSION: Outbreak detection relies on typing of isolates, usually by analysing one isolate per patient. We here show that this approach is insufficient for outbreak surveillance of VRE in highly vulnerable patients, as it does not take into account VRE population heterogeneity and horizontal gene transfer of the resistance element.

AB - OBJECTIVES: Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis (VRE) are a common cause of healthcare-associated infections. Whole genome sequencing-based typing methods yield the highest discriminatory power for outbreak surveillance in the hospital. We analysed the clonal composition of enteric VRE populations of at-risk patients over several weeks to characterise VRE population diversity and dynamics.METHODS: Five bone marrow transplant recipients (three colonised with vanA-positive isolates, two colonised with vanB-positive isolates) contributed three rectal swabs over a course of several weeks. Fourteen VRE colonies per swab were analysed by core genome multi locus sequence typing (cgMLST) and typing of the van-element.RESULTS: VRE populations were clonally diverse in three of five patients, and population composition changed dynamically over the time of observation. Besides new acquisition of VRE isolates, shared van-elements localised on nearly identical plasmids between clonally different isolates indicate horizontal gene transfer as a mechanism behind VRE population diversity within single patients.CONCLUSION: Outbreak detection relies on typing of isolates, usually by analysing one isolate per patient. We here show that this approach is insufficient for outbreak surveillance of VRE in highly vulnerable patients, as it does not take into account VRE population heterogeneity and horizontal gene transfer of the resistance element.

U2 - 10.1016/j.jgar.2022.01.027

DO - 10.1016/j.jgar.2022.01.027

M3 - SCORING: Journal article

C2 - 35134550

VL - 28

SP - 267

EP - 273

JO - J GLOB ANTIMICROB RE

JF - J GLOB ANTIMICROB RE

SN - 2213-7165

ER -