Prevalence of Quinolone Resistance Genes among Some Clinical Gram-negative Isolates

Abstract

Background: Gram-negative bacilli are pivotal in both nosocomial and community-acquired illnesses, making them an essential category of bacteria. Quinolones are the antibiotics of choice for the treatment of both illnesses. Resistance to quinolones has been often documented during the last three decades due to their extensive therapeutic use. The resistance mechanisms were thought to be solely chromosome-encoded, including alterations of molecular targets (DNA gyrase and topoisomerase IV), reduced outer-membrane permeability, and upregulation of naturally existing efflux systems. The establishment of plasmid-mediated quinolone resistance (PMQR) has been documented since 1998. Objective: The aim of this work is to detect antimicrobial susceptibility as well as molecular studies on Gram-Negative clinical isolates. Methodology: A total of 150 clinical isolates were subjected to antimicrobial susceptibility testing using the Kirby Bauer disc diffusion method and the Polymerase chain reaction (PCR) to detect the production of plasmid-mediated quinolone resistance genes (PMQR). Results: Out of the 150 clinical isolates, 102 (68%) strains were resistant to fluoroquinolones; where E. coli-resistant strains were 27 (18%), K. pneumoniae were 30 (20%), and P. aeruginosa were 45 (30%). Conclusion: The high prevalence of PMQR-producing bacteria among various infections underscores the necessity of monitoring them. Additionally, it is imperative to raise the awareness of physicians and healthcare providers in order to mitigate the transmission of these resistant isolates.