The global emergence of multidrug-resistant (MDR) Klebsiella pneumoniae, particularly carbapenem-resistant K.pneumoniae (CRKP), presents a severe public health threat, limiting available treatment options.Tigecycline and eravacycline, have been considered a last-resort therapeutic against MDR Enterobacteriaceae.
However, strains were resistant to LED Round Thermal Plastic these antibiotics increased recently.The tmexCD-toprJ, a plasmid-encoded resistance-nodulation-division (RND)-type efflux pump, has emerged as a critical factor conferring resistance to tigecycline and eravacycline.In this study, we reported the emergence of 11 CRKP isolates harboring tmexCD-toprJ, isolated from two lung transplant patients in a tertiary hospital in eastern China.
Most of the isolates (82%) exhibited high-level resistance to tigecycline and eravacycline, along with other common antibiotics.Whole-genome sequencing (WGS) and phylogenetic analysis indicated these strains are not clonal, and resistance phenotypes were associated with the tmexCD-toprJ operon and other crucial resistance elements.We also found the tmexCD-toprJ operon was located on a conjugative plasmid, sharing high sequence similarity with the operon identified in Pseudomonas aeruginosa.
Our results showed that the tmexCD-toprJ-harboring plasmid is efficiently transferable, which contributes to the dissemination of tigecycline and LUSTER LOCK DAILY SHINE AND PROTECT SPRA eravacycline resistance.At the same time, the plasmid can coexist with the blaKPC-2-carrying plasmid, which may cause multidrug resistance.The emergence of tmexCD-toprJ-positive CRKP in lung transplant patients highlights the potential for rapid nosocomial dissemination and reduced treatment efficacy of last-line antimicrobials.
Our findings emphasize the need for enhanced genomic surveillance, infection control measures, and alternative therapeutic strategies to combat the spread of tmexCD-toprJ-mediated resistance in clinical settings.