Detection of qnr genes and gyrA mutation to quinolone phenotypic resistance of UTI pathogens in Bangladesh and the implications : resistance UTI pathogens Bangladesh
Background: Plasmid-mediated quinolone resistance (PMQR) genes and mutations within the quin-olone resistance-determining regions (QRDRs) bequeath to the advent of quinolone-resistant path-ogenic microbes. This research was designed to assess the roles of three PMQR genes, qnrA, qnrB, and qnrS, and any mutation in the gyrA gene in the QRDR region as a process of quino-lone/fluoroquinolone resistance to urinary tract infection (UTI) bacteria in Bangladesh to guide fu-ture management of UTIs. Methods: Pathogens from UTIs were isolated and identified, and their phenotype antibiotic susceptibilities were tested for lomefloxacin, ofloxacin, ciprofloxacin, and na-lidixic acid. Polymerase chain reaction (PCR) detected the qnrA, qnrB, and qnrS genes. PCR and se-quencing were performed to evaluate any mutation within the QRDRs of the gyrA gene. Results: Of 100 UTI bacteria, phenotypic resistance was observed in 95.0%, 89.0%, 83.0%, and 71.0% against lomefloxacin, nalidixic acid, ofloxacin, and ciprofloxacin, respectively. PMQR genes: qnrS, qnrA, and qnrB genes were found in 54.0%, 1.0%, and 4.0% of isolates, respectively. Sequencing the gyrA gene revealed single mutation (Ser-83 to Leu) and double mutations (Ser-83 to Leu and Asp-87 to Asn). PMQR genes showed a statistically non-significant association with phenotypic resistance. Conclu-sions: This study confirms the presence of QRDR mutations that were independent of PMQR quino-lone resistance genes. Consequently, high resistance against quinolones among uropathogens is ev-ident, and their future use needs to be moderated
