Detection of Quinolone Resistance Qnr Genes and its Association with Extended Spectrum Β-Lactamase and Carbapenemase Genes in Qnr Positive Enterobacteriaceae in a Tertiary Hospital in Bangladesh

Abstract

Background: Multidrug resistance in Enterobacteriaceae including resistance to quinolone is dramatically increasing day by day. Widespread use of quinolones against Enterobacteriaceae has contributed to the rise of drug resistance. Resistance to quinolone is generally due to chromosomal mutations in genes coding for the target molecules of these agents, namely the DNA gyrase and topoisomerase IV enzymes. Recently, a multiresistance plasmid is discovered that encodes transferable resistance to quinolones; its prevalence is increasing gradually throughout the world. Plasmids have a crucial role in the dissemination of drug resistance genes like plasmid mediated quinolone resistant (PMQR) genes, extended-spectrum β-lactamase (ESBL) genes and carbapenemase genes. Objective: To detect the prevalence of quinolone resistance Qnr genes and its association with extended-spectrum β-lactamase and carbapenemase genes in Qnr positive Enterobacteriaceae. Methods: A prospective cross sectional study was conducted from January 2015 to December 2015 at Dhaka Medical College hospital, Bangladesh. A total of 270 Enterobacteriaceae were isolated from 340 samples collecting from inpatient and outpatient departments of DMCH irrespective of age, sex and antibiotic intake. Qnr determinant screening among ciprofloxacin resistant strains were conducted using PCR amplification. Searching of Extended-spectrum β-lactamase and carbapenemase genes in Qnr positive Enterobacteriaceae were conducted also by using PCR. Results: The Qnr genes were detected in 141 (62.67%) of the 225 quinolone resistant isolates by using PCR. Highest proportion of QnrS (n =84, 59.57%) were detected followed by QnrB (n =70, 49.64%) and QnrA (n =33, 23.40%). In the present study, 48 ESBL producers were identified among 141 Qnr positive strains. Highest proportion of CTX-M-15 (n= 38, 69.09%) were detected followed by TEM (n= 20, 36.36%) and OXA-1 (n= 16, 29.09%). In the present study, 22 carbapenemase producers were .....