Pseudomonas aeruginosa Clinical Isolates in Nepal Coproducing Metallo-β-Lactamases and 16S rRNA Methyltransferases

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Multidrug-resistant (MDR) Pseudomonas aeruginosa poses a significant global health threat.
• Carbapenemases and 16S rRNA methyltransferases are key mechanisms of antibiotic resistance.
• Limited data exists on the co-occurrence of these resistance genes in P. aeruginosa from Nepal.

Purpose of the Study:

• To investigate the prevalence of carbapenemase and 16S rRNA methyltransferase genes in MDR P. aeruginosa clinical isolates from Nepal.
• To characterize novel resistance gene variants identified in these isolates.

Main Methods:

• Phenotypic and genotypic analysis of 11 MDR P. aeruginosa clinical isolates.
• Detection of carbapenemase genes (e.g., blaDIM, blaNDM, blaVIM) using molecular methods.
• Identification of 16S rRNA methyltransferase genes (e.g., rmtB, rmtF) and sequencing for variant analysis.

Main Results:

• Four out of 11 isolates harbored carbapenemase genes (DIM-1, NDM-1, VIM-2).
• Five isolates carried 16S rRNA methyltransferase genes (RmtB4, RmtF2).
• A novel variant, RmtF2, with a K65E substitution, was identified.

Conclusions:

• This is the first report of carbapenemase- and 16S rRNA methyltransferase-co-producing P. aeruginosa clinical isolates in Nepal.
• The findings highlight the emergence of complex antibiotic resistance mechanisms in this region.
• Continuous surveillance is crucial to monitor and combat the spread of MDR pathogens.