Occurrence of quinolone resistance genes qep, QnrA, QnrB and QnrS in uropathogenic E. coli from female clinical samples at Makerere University College of Health Sciences

Abstract

Drug resistant Escherichia coli (E Coli) is the leading cause of community and hospital acquired urinary tract infections affecting approximate 150 million people each year worldwide. Uropathogenic Escherichia coli (UPEC) strains accounts for the main causative agents, this increase in prevalence is attributed to the indiscriminate use of antibiotics. Objectives The purpose of this study is to evaluate the prevalence of quinolone resistant genes qep, qnrA, qnrB and qnrS among Escherichia coli isolates obtained from female patients at the microbiology laboratory Makerere University college of Health Sciences. Two mechanisms of quinolone resistance have been established: 1) alterations in the targets of quinolones and decreasing drug accumulation inside cells through membrane impermeability or an over expression of efflux pump. 2) Mutations in specific domains of qep, qnrS, qnrA and qnrB causing variations in single amino acid of either gyrase or topoisomerase IV leading to resistance to quinolones. Methods and materials The study was a cross sectional study carried out using female samples stored in Makerere university microbiology laboratory and known to have quinolone resistance. From the archived samples, DNA extraction was done, polymerase chain reaction and agarose gel electrophoresis. Outcomes In total, 21 isolates resistant to ciprofloxacin and nalidixic acid. The highest rates of antibiotic resistance were obtained for nalidixic acid (100%), ciprofloxacin (80%). Of the 21 quinoloneresistant strains, 01 (7.1%) isolates harbored qep genes. None of the isolates harboured the qnrA gene, qnrB and qnrS. Conclusion These findings suggest a possible resistance to fluoroquinolone is of high interest for better management of patients and control of antimicrobial resistance in Uganda.