Clinical phenotype and molecular characteristics of carbapenem-resistant hypervirulent Klebsiella pneumoniae causing multi-site infection

Objective To analyze the clinical phenotype and molecular characteristics of three Carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKp) strains isolated from different sites of the same patient, providing an experimental basis for clinical anti-infection treatment and nosocomial infection prevention and control. Methods The collected strains were tested for antimicrobial susceptibility using an automatic drug sensitivity analyzer. Whole-genome sequencing was performed to analyze the presence of resistance and virulence genes and to determine the classification and homology of the three strains. Results The three K. pneumoniae strains were classified as ST11/K47/O13. Whole-genome sequencing revealed that all strains carried the KPC -type carbapenemase gene, and the high-virulence genes, rmpA2, iroB and iutA , along with three plasmids. Antimicrobial susceptibility testing showed that all strains were resistant to carbapenems, including imipenem and meropenem. Conclusion The three clinically isolated K. pneumoniae strains were highly virulent and carbapenem-resistant, all carrying the KPC resistance gene. They caused multi-site infections through hematogenous dissemination. These findings highlight the need for heightened clinical vigilance and strengthened monitoring, prevention, and control of drug-resistant infections.