Genetic Fingerprint of Klebsiella pneumoniae Virulence: A Systematic Review

Background: Klebsiella pneumoniae is a globally relevant pathogen whose growing association between hypervirulence and antimicrobial resistance represents a major public health challenge. Methods: A systematic review was performed following the PRISMA 2020 guidelines. Studies published between 2005 and 2025 were searched in Google Scholar, Scopus, PubMed and Science Direct that reported the molecular detection of virulence genes in clinical isolates. Results: A total of 676 studies were included, in which 475 virulence genes were reported. A progressive increase in their detection was observed, Hypervirulent strains were associated with a higher proportion of genes associated with capsule and hypermucoviscosity, while classical strains were associated with a higher representation of adhesion and biofilm genes. Conclusions: The virulence of K. pneumoniae is organized into functional modules dominated by iron acquisition and capsular regulation. These findings support the prioritization of key determinants for molecular surveillance and the study of the global distribution and temporal trends of this pathogen.