The prevalence of carbapenem-resistant Enterobacterales and the emergence of novel ST11-KL30 carbapenem-resistant Klebsiella pneumoniae in Xinjiang, China

Objectives

To address the lack of research on the prevalence of carbapenem-resistant Enterobacterales (CREs) in Xinjiang, China, and elucidate the genomic characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP) ST11-KL30.

Methods

CREs were collected in Xinjiang from 2021 to 2023. The antimicrobial susceptibility testing of carbapenems was performed via agar dilution method. Whole-genome sequencing was completed on the Illumina platform, and subsequent genomic analyses of CRKP, such as sequencing typing, K-locus and O-locus identification, virulence score assessment, and phylogenetic analysis, were performed. The virulence of CRKP isolates was determined in vitro and in vivo, and biofilm formation was assessed by crystal violet staining. Additionally, the virulence plasmid was reconstructed, and the formation of CRKP ST11-KL30 was revealed based on genome data from public database.

Results

Eighty-five CRE isolates were collected, among which CRKP was most prevalent (68/85). KPC was the most dominant carbapenemase (60/68) in CRKP, while NDM-type carbapenemase was more prevalent in other species. ST11 was the dominant CRKP clone and was phylogenetically divided into three clusters: ST11-KL64, ST11-KL47 and ST11-KL30. CRKP ST11-KL30 is a novel recombinant clone that harbours a pK2044-like virulence plasmid and can be derived from ST11-KL64 by obtaining an ∼57 kb region from ST29-KL30. Compared to ST11-KL47 and ST11-KL64, ST11-KL30 had lower virulence, but had enhanced biofilm formation.

Conclusions

We describe the prevalence of CRE prevalence southern Xinjiang and report the emergence of a region-specific clone. Our findings underscore the potential dissemination of ST11-KL30, which warrants increased monitoring in the future.