Convergencia de hipervirulencia y resistencia a carbapenémicos en Klebsiella pneumoniae

Abstract

The convergence of hypervirulence and carbapenem resistance in Klebsiella pneumoniae (CR-hvKp) has emerged as a growing clinical concern in recent years. Initially regarded as an opportunistic pathogen affecting immunocompromised individuals, hypervirulent K. pneumoniae (hvKp) now poses a threat to healthy individuals and exhibits significant antibiotic resistance. This study, part of the KLEVIRE project, examines the virulence and carbapenem resistance mechanisms of hvKp strains identified during routine screening at a university hospital in Spain. Whole-genome sequencing (WGS) revealed variability in capsular serotypes and virulence gene distribution, with high prevalence of genes such as rmpA, uge, fim, urea, and wabG, as well as important resistance genes like blaOXA-48 and blaCTX-M-15. Conjugation assays confirmed the transfer of blaOXA-48 from CR-hvKp K. pneumoniae to Escherichia coli, highlighting the potential for horizontal gene transfer. Furthermore, diverse biofilm production levels and, surprisingly, motile strains with swimming, swarming, and twitching motilities were observed, despite K. pneumoniae being considered as non-motile. Additionally, infection in Galleria mellonella confirmed the high virulence of the strains. These findings underscore the significant clinical challenge posed by the CR-hvKp strains, emphasizing the need for further investigation into underlying mechanisms to effectively combat this increasing threat.