澳大利亚西部一所教学医院携带 van 基因的屎肠球菌的分子流行病学变迁：一项长达 15 年的回顾性研究。

The changing molecular epidemiology of Enterococcus faecium harbouring the van operon at a teaching hospital in Western Australia: A fifteen-year retrospective study.

机构信息

Antimicrobial Resistance and Infectious Diseases Research Laboratory, Murdoch University, Western Australia, Australia.

Antimicrobial Resistance and Infectious Diseases Research Laboratory, Murdoch University, Western Australia, Australia; PathWest Laboratory Medicine-WA, Fiona Stanley Hospital, Western Australia, Australia.

出版信息

Int J Med Microbiol. 2022 Jan;312(1):151546. doi: 10.1016/j.ijmm.2021.151546. Epub 2021 Dec 14.

DOI:10.1016/j.ijmm.2021.151546

PMID:34922099

Abstract

INTRODUCTION

Enterococcus faecium is an opportunistic pathogen that has become one of the leading causes of hospital acquired infection that are resistant to multiple critically important antimicrobials.

AIM

The objective of the study was to describe the molecular characteristics and relationship between major strains of E. faecium harbouring the van operon and to determine if the strains had increasing virulence and antimicrobial resistance determinants over time.

METHODS

E. faecium harbouring the van operon detected using PCR from surveillance rectal swabs of patients that were admitted to high-risk units at a Perth teaching hospital from 2001 to 2015 were retrospectively analysed using a whole genome sequencing and bioinformatics approach.

RESULTS

ST18, ST78, ST80, ST173, ST203 and ST555 were identified as the major STs accounting for 93.7% of E. faecium isolates. Except for ST173, major STs identified at Royal Perth Hospital (RPH) have been reported across Australia and internationally. Isolates from each ST formed independently branched phylogenetic clusters with each harbouring unique virulence and antimicrobial resistance profiles. Depending on the ST, different genes conferring resistance to similar antimicrobial classes were identified. Except for ST80 which harboured the vanA type operon, all major strains harboured the vanB operon conferring only vancomycin resistance.

CONCLUSION

Major strains of E. faecium isolated over 15-years showed unique virulome and resistome profiles with no indication of increasing virulence or antimicrobial resistance determinants. Strains were distantly related and the acquisition of different genes encoding similar antimicrobial resistances suggest the independent evolution of each strain.

DATA SUMMARY

The whole genome sequences of all isolates from this study are accessible from the NCBI-SRA database under project number PRJNA575940 and PRJNA524213. Published reference sequence Aus0004 was obtained from NCBI-SRA under project number PRJNA86649 DOI:10.1128/JB.00259-12.

摘要

简介

屎肠球菌是一种机会致病菌，已成为对多种重要抗菌药物耐药的医院获得性感染的主要原因之一。

目的

本研究的目的是描述携带 van 基因簇的屎肠球菌主要菌株的分子特征和关系，并确定这些菌株是否随着时间的推移具有增加的毒力和抗微生物药物耐药性决定因素。

方法

从 2001 年至 2015 年期间，在西澳教学医院的高危病房住院的患者的直肠拭子中，使用 PCR 检测到携带 van 基因簇的屎肠球菌，对其进行了回顾性分析，采用全基因组测序和生物信息学方法。

结果

ST18、ST78、ST80、ST173、ST203 和 ST555 被确定为主要 ST，占屎肠球菌分离株的 93.7%。除 ST173 外，在皇家珀斯医院（RPH）发现的主要 ST 已在澳大利亚和国际上报道。来自每个 ST 的分离株形成独立的分支进化群，每个 ST 都具有独特的毒力和抗微生物药物耐药谱。根据 ST 的不同，鉴定出不同的基因赋予了对类似抗菌药物类别的耐药性。除 ST80 携带 vanA 型基因簇外，所有主要菌株均携带 vanB 基因簇，仅赋予万古霉素耐药性。