Clinical characteristics and molecular evolution of ST11-KL64 carbapenem-resistant hypervirulent <i>Klebsiella pneumoniae</i> co-producing KPC-2 and NDM-1 from China

The emergence of bacterial pathogens that combine hypervirulence with advanced antimicrobial resistance poses a significant challenge for modern healthcare. This study comprehensively analyzes a concerning clinical strain: ST11-KL64 <i>K. pneumoniae</i> co-harboring both KPC-2 and NDM-1 carbapenemases. We demonstrate that this strain successfully integrates multiple resistance mechanisms, hypervirulence determinants, and remarkable genetic stability without observable fitness costs-a combination that significantly complicates treatment and infection control. Critically, the stable maintenance of its resistance plasmids without antibiotic selection highlights the potential for persistent colonization and transmission. These findings underscore an evolving threat in the landscape of multidrug-resistant infections and emphasize the urgent need for enhanced surveillance, robust diagnostic approaches, and novel therapeutic strategies to address such challenging pathogens.