Global emergence and transmission dynamics of carbapenemase-producing Citrobacter freundii sequence type 22 high-risk international clone: a retrospective, genomic, epidemiological study

作者：Qiaojun Wang, Longjie Zhou, Xiaoling Chen, Jiayao Yao, Xinran Sun, Kai Peng, Yanyun Gao, Edward J. Feil, Yunsong Yu, Zhiqiang Wang, Ruichao Li, Xi Li · 发表于：The Lancet Microbe · 年份：2025 · DOI：10.1016/j.lanmic.2025.101149 · 被引用次数：14 · 研究领域：Antibiotic Resistance in Bacteria、Infections and bacterial resistance、Bacterial Identification and Susceptibility Testing

BACKGROUND: Carbapenemase-producing Citrobacter (CPC) species have recently been recognised as emerging pathogens associated with nosocomial infections in humans. The increased rate of Citrobacter freundii infections is a public health concern and there is a paucity of genomic data regarding its global transmission dynamics. We aimed to characterise the genetic features of CPC species, and their associated carbapenemase-encoding plasmids, obtained from hospitalised patients in China and from publicly available global data, with a particular focus on high-risk clones. METHODS: was constructed from the National Center for Biotechnology Information (NCBI) RefSeq database to provide insights into their diversity and distribution. All carbapenemase-producing Citrobacter freundii genomes from the NCBI GenBank database were incorporated in the comparative genomic analyses. Bayesian phylogeographical analysis and growth rate assays were carried out to characterise the high-risk C freundii sequence type (ST) 22 clone. FINDINGS: 1724 Citrobacter species isolates were collected from diverse clinical specimens, with 48 identified as CPC species. Citrobacter koseri (22 [46%] of 48) and C freundii (20 [42%]) were the predominant CPC species. Comparative analysis found C freundii carried significantly higher median numbers of plasmid replicons (5·0 [IQR 3·3-6·0] vs 2·0 [2·0-3·0]; p<0·0001) and acquired antimicrobial resistance genes (12·0 [7·3-15·8] vs 3·0 [3·0-5·3]; p<0·0001) than did C ko...