Plasmid-mediated Quinolone resistance genes in Pseudomonas aeruginosa isolates of burn infection

Plasmid-dependent resistance to quinolones is increasingly spreading among P. aeruginosa isolates worldwide. In this study, the evaluation of antibiotic resistance to quinolones in P. aeruginosa isolated from burn wound samples was investigated. In this descriptive study, 73 burn isolates of P. aeruginosa were collected. Antibiotic susceptibility of the isolates was assessed by the disk diffusion method. Then, the frequency of the aac(6’)-Ib, qnrS, qnrB, and qnrA genes was determined by PCR. The highest resistance was related to the antibiotics Nalidixic acid (100%), Imipenem (98.7%), Ciprofloxacin (97.2%), Cefepime (100%), Meropenem (97.2%), Levofloxacin (100%), and Ofloxacin (100%). Among 73 P. aeruginosa isolates, 4 (5.5%) strains containing the aac(6')-Ib gene, 3 (4.1%) strains containing the qnrA gene, 3 (4.1%) strains with the qnrB gene, and 2 (7.2%) strains containing the qnrS gene were detected. In total, out of 73 strains of P. aeruginosa isolated from burns, 12 strains (16.5%) had one or four plasmids carrying quinolone resistance genes alone or simultaneously. The expansion of quinolone-resistant plasmid genes plays an important role in the prevalence of P. aeruginosa quinolone-resistant strains in burns, and control of Pseudomonas burn wound infections with quinolones has proven difficult.