First report of an <i>Escherichia coli</i> ST131 clinical isolate co-harboring <i>bla</i> _KPC-2 and <i>bla</i> _NDM-13 on an IncB/O/K/Z plasmid in China

Antimicrobial resistance has become a serious global public health concern, severely limiting therapeutic options. The global proliferation of carbapenem-resistant <i>Enterobacteriaceae</i>, driven by plasmid-mediated horizontal gene transfer of carbapenemase-encoding elements, constitutes a critical antimicrobial resistance crisis. This study provides the first evidence of <i>bla</i>_KPC-2 and <i>bla</i>_NDM-13 co-occurring on an IncB/O/K/Z plasmid (pB5-KPC-NDM), as well as the first detection of these genes in a clinical <i>Escherichia coli</i> isolate (B5). Phenotypic and genotypic analyses demonstrate efficient horizontal transfer capacity and stability across bacterial generations of pB5-KPC-NDM, facilitating the spreading of multidrug resistance. This dual carbapenemase co-localization represents a pivotal escalation in the dissemination potential of resistance and consequently heightens the threat of its spread worldwide. These findings emphasize the critical need for enhanced genomic surveillance programs and the implementation of stringent infection control measures to mitigate the global dissemination of such multidrug-resistant plasmids carrying high-risk carbapenemase variants.