Peng Lianghui, Song Jingjie, Sun Hongli, Zhang Xiwei, Huang Yulan, Zeng Shihan, Zhou Zhuoyang, Li Xiaoyan, Zhuo Chao
Department of Clinical Laboratory, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, China.
Department of Clinical Laboratory, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Int J Antimicrob Agents. 2025 Mar;65(3):107412. doi: 10.1016/j.ijantimicag.2024.107412. Epub 2024 Dec 19.
The detection rate of vancomycin-resistant Enterococcus faecium (VREfm) displayed a dramatic increase in Guangdong, China, from 2021 to 2023, for which the molecular epidemiology and genomic characteristics remain largely unexplored. In this study, we investigated the genetic features and epidemiology of VREfm isolates in Guangdong.
A total of 54 Guangdong VREfm isolates were collected from three tertiary hospitals in Guangdong. We preformed antimicrobial susceptibility tests, whole genome sequencing, risk factor analysis, and bioinformatics analysis to conduct this research.
Our investigation indicated that VREfm isolates were highly clonal and multidrug-resistant ST80 Enterococcus faecium harboring vanA-positive plasmid. Phylogenetic analysis based on single-nucleotide polymorphisms (SNPs) demonstrated that VREfm isolates exhibited minimal genetic similarity to previously reported E. faecium in China, whereas they exhibited high genomic similarity to an India strain A10290 isolated in 2019 and Hiroshima isolates detected in 2020, indicative of a possible exogeneous import. The genetic environment of cps region showed a novel type of wzy gene cluster involved in capsule polysaccharide (CPS) biosynthesis flanked by ISEf1 and IS16 identified in VREfm isolates, which displayed a remarkably divergence from the downstream of putative cpsABCD region in other sequence types (STs) E. faecium. Heat map of plasmid-mediated virulence factors suggested that several predicted proteins including Cag pathogenetic island proteins existed in VREfm isolates at a high frequency.
This study highlighted the importance of ongoing surveillance to track the dynamic dissemination of multidrug-resistant ST80 VREfm isolates harboring multiple virulence genes in Guangdong Province, China.
2021年至2023年期间，中国广东省耐万古霉素屎肠球菌（VREfm）的检出率急剧上升，但其分子流行病学和基因组特征在很大程度上仍未得到探索。在本研究中，我们调查了广东省VREfm分离株的遗传特征和流行病学情况。
从广东省的三家三级医院收集了总共54株广东VREfm分离株。我们进行了药敏试验、全基因组测序、危险因素分析和生物信息学分析来开展这项研究。
我们的调查表明，VREfm分离株具有高度克隆性且为多重耐药的ST80屎肠球菌，携带vanA阳性质粒。基于单核苷酸多态性（SNP）的系统发育分析表明，VREfm分离株与中国此前报道的屎肠球菌遗传相似性极低，而它们与2019年分离的印度菌株A10290和2020年检测的广岛分离株具有高度基因组相似性，这表明可能存在外源输入。cps区域的遗传环境显示，在VREfm分离株中鉴定出一种新型的wzy基因簇，参与荚膜多糖（CPS）生物合成，其两侧为ISEf1和IS16，与其他序列类型（STs）屎肠球菌假定的cpsABCD区域下游存在显著差异。质粒介导的毒力因子热图表明，包括Cag致病岛蛋白在内的几种预测蛋白在VREfm分离株中高频存在。
本研究强调了持续监测对于追踪中国广东省携带多种毒力基因的多重耐药ST80 VREfm分离株动态传播的重要性。
