Molecular identification of plasmid-mediated quinolone resistance genes among klebsiella pneumoniae clinical isolates from southwest Iran

Abstract

In recent years, the resistance rate to quinolone antibiotics has been increasing in Klebsiella pneumoniae. Plasmid-mediated quinolone resistance (PMQR) genes are one of the factors causing resistance to quinolones. Hence, this study aimed to determine the incidence of PMQR genes in clinical K. pneumoniae isolates from southwest Iran. In total, 96 K. pneumoniae isolates were identified during the study period. Sixty-seven (69.8%) isolates were resistant to at least one quinolone antibiotic. Resistance rates to levofloxacin, norfloxacin, nalidixic acid, ofloxacin, and ciprofloxacin were 50% (48/96), 56.3% (54/96), 60.4% (58/96), 62.5% (60/96), and 68.8% (66/96), respectively. The highest frequencies of PMQR genes were related to qnrS, aac (6’)-Ib-cr, and qnrB genes with 85.1% (57/67), 83.6% (56/67) and 65.7% (44/67), respectively. The qnrD, qnrC, qepA, and qnrA were detected in 23.9% (16/67), 19.4% (13/67), 13.4% (9/67), and 6.0% (4/67) of isolates, respectively. This study was the first to report a high-frequency rate of PMQR genes in K. pneumoniae isolates from the clinical setting of Ahvaz, southwest Iran. As a result, antibiotic prescribing policies should be amended to hinder the further spread of PMQR genes in the studied region.