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.