Frequency of qnr and aac(6’)Ib-cr Genes Among ESBL-Producing Klebsiella pneumoniae Strains Isolated from Burn Patients in Kermanshah, Iran

Abstract

Background: Assessment of bacteria such as Klebsiella pneumonia has shown that Plasmid-mediated quinolone resistance (PMQR) affects antibiotics resistance (e.g., quinolones). Objectives: We studied the prevalence of qnr and aac(6’)Ib-cr genes in extended-spectrum beta-lactamase (ESBL)-producing K. pneumonia strains isolated from burn wounds of patients in the city of Kermanshah, Iran. Methods: This descriptive-analytical study was conducted on 126 K. pneumonia strains isolated collected from burn wounds. Biochemical tests were used to detect the strains. The frequency of the ESBL-producing isolates was determined by phenotypic tests of the combination disk (CD) method after determining the antibiotic susceptibility pattern of the isolates through the Kirby-Bauer disc diffusion test. The prevalence of the qnr and aac(6’)-Ib-cr genes was determined using their special primers as well as polymerase chain reaction (PCR). Results: Of the 126 K. pneumonia isolates, 52 (41.3%) were identified as ESBL-producing strains. ESBL-producing isolates showed higher resistance against antibiotics than non-ESBL-producing ones. PMQR relevance and resistance to ciprofloxacin were, respectively, determined at 80.76% and 59.6%. The most frequent gene was aac(6’)-Ib-cr (n = 70, 55.6%), followed by the qnrB (n = 44, 34.9%. Conclusions: This study showed a high prevalence of qnr genes in ESBL-producing K. pneumonia isolates and antibiotic resistance. Given the horizontal transmission of antibiotic resistance genes among bacteria by mobile genetic elements, timely identification of infections caused by ESBL-producing and antimicrobial-resistant K. pneumonia strains is of paramount importance.

Characterization of Carbapenemase-Producing Klebsiella pneumoniae Isolates from Two Romanian Hospitals Co-Presenting Resistance and Heteroresistance to Colistin

“…Instead, consistent with Ruppe et al [ 33 ], the BC9_TM strain was found to possess the aac(6′)-Ib-cr5 gene but without phenotypic expression of amikacin resistance. Vaziri et al underscored the fundamental role of the qnrB gene in the K. pneumoniae genome, which, in association with the aac(6′)-Ib-cr5 gene, contributes to increased resistance to aminoglycosides, fluoroquinolones, and cephalosporins [ 36 ], a conclusion that was not supported by our findings. A recent nationwide epidemiological survey conducted in Greece confirmed a divergence between the resistance phenotype and the AME genotype for aminoglycosides, probably as a consequence of various competing resistance mechanisms associated with the distinct catalytic activities of AME genes [ 37 ].…”

Molecular characterization of plasmid-mediated quinolone resistance (PMQR) and ESBLs-producing Klebsiella pneumonia isolated from an Iranian teaching hospital

“…Frequencies of oqxA and B genes found in this study are higher than those reported by Azargun in Tabriz, Iran in 2018 which were 33.7 for oqxA and 20.6% for oqxB [9]. Previous studies have found that the prevalence of PMQR genes is more common in ESBL-producing K. pneumoniae [4,9,20]. We found that PMQR genes (aac(6′)-Ib-cr, qnrS, qnrB) were also be detected in strains containing ESBL determinants.…”

“…CTX-M-15type ESBL-producing strains have especially increased in recent years [5][6][7]. Presence of PMQR determinants including qnr genes, aac (6')-Ib-cr, and e ux pumps genes qepA, qepA2, and oqxAB confer reduced susceptibility to uoroquinolones and facilitate selection of uoroquinolone resistance in K. pneumoniae [4,8].…”

“…One of the important resistance mechanisms of Enterobacterales, including K. pneumoniae, is the production of extended-spectrum beta-lactamases (ESBLs), and plasmid-mediated quinolone resistance (PMQR) genes that have been detected in clinical isolates. ESBLs are plasmid-mediated enzymes that hydrolyze oxyimino-β lactam agents such penicillins, cephalosporins, and monobactams [3,4]. ESBL genes are classi ed in several types including bla CTX−M , bla SHV , and bla TEM .…”

Investigation of plasmid‐mediated quinolone resistance genes among clinical isolates of Klebsiella pneumoniae in southwest Iran

“…Klebsiella pneumoniae is one of the pioneer pathogens in causing a wide range of nosocomial and community‐acquired infections, including septicemia, pneumonia, meningitis, soft tissue infections, and urinary tract infections 1,2 . Global concerns about this pathogen are growing due to the increased incidence of resistance to quinolones and other classes of antibiotics, as well as the declining effectiveness of treating infections 3,4 .…”