Plasmid-mediated quinolone resistance determinants in Enterobacteriaceae from urine clinical samples

Abstract

Plasmid-mediated quinolone resistance (PMQR) determinants including, qnrA, qnrB, qnrC, qnrD, qnrS, aac(6')-Ib-cr, oqxAB, and qepA, were investigated in 214 Enterobacteriaceae strains from urine clinical samples. Antimicrobial susceptibility testing for ciprofloxacin, ceftriaxone, and imipenem was performed by broth microdilution method. All strains were screened for PMQR genes by PCR. Virulence determinants, namely afa, pap, pil, sfa/foc, and kpsMT of eight Escherichia coli strains proven positive for at least one qnr gene, were investigated by PCR. All of the eight investigated strains carried the pil gene, showing that P fimbria is a common virulence determinant among qnr positive E. coli. Out of 214 tested strains, 38 yielded any PMQR determinant, altogether 45 genes were detected namely, 6 qnrA, 1 qnrB, 2 qnrD and 8 qnrS, 9 aac(6')-Ib-cr, and 19 oqxAB; however, neither qepA nor qnrC were detected. Notably, 18 Klebsiella spp., harbored oqxAB, nine E. coli were positive for qnrS and two Morganella morganii yielded qnrD resistance determinant. In this study, we demonstrated 17.7% prevalence of PMQR-positive Enterobacteriaceae and first reported qnrD-resistance determinant in Hungary. Altogether, 25 PMQR-positive strains were susceptible or low-level resistant to ciprofloxacin with minimum inhibitory concentration (MIC) between 0.06 and 1 mg/L, suggesting that prevalence of PMQR determinants is underestimated and screening among clinical isolates exhibiting reduced susceptibility is necessary. Fluoroquinolone resistance breakpoints of Enterobacteriaceae were revised in 2017 by European Committee of Antimicrobial Susceptibility Testing indicating ciprofloxacin susceptibility only until 0.25 mg/L MIC value.

Prevalence of extended spectrum beta lactamase and plasmid mediated quinolone resistant genes in strains of Klebsiella pneumonia, Morganella morganii, Leclercia adecarboxylata and Citrobacter freundii isolated from poultry in South Western Nigeria

“…The most prevalent PMQR gene is oqx B with more abundance in Klebsiella pneumonia strains. ( Yuan et al, 2012 ) and Szabó et al (2018) also reported the presence of oqx AB gene in all human K. pneumoniae strains investigated. However, in a recent study on Klebsiella strains isolated from broiler, qnr B was the most dominant followed by qnr S and with low prevalence of qep A and qnr A ( Wu et al, 2016 ).…”

“…The observed resistance may be due to an univestigated gene. Resistance of Morganella morganii to quinolones has been linked to qnr D, two new gyr B mutations (S463A, S464Y) and one par C mutation (S80I) ( Nasri et al, 2014 ; Szabó et al, 2018 ).…”

An evaluation of multidrug-resistant Escherichia coli isolates in urinary tract infections from Aguascalientes, Mexico: cross-sectional study

“…qnrD gene was found in 4.5% of the isolates. Previous papers reported qnrD in bacteria isolated from rooks [ 51 ], pigs [ 15 ] and humans clinical isolates of Salmonella enterica serovar Kentucky, serovar Bovismorbificans, Proteus mirabilis and Morganella morganii [ 52 , 53 ], as well as in E. coli from dogs [ 54 ]. In accordance to others studies [ 19 , 55 , 56 ], qepA was not identified.…”

Plasmid copy number and qnr gene expression in selection of fluoroquinolone-resistant Escherichia coli

“…In Northwest Iran, prevalence of PMQRs in Enterobacteriaceae isolated from UTIs showed a very high prevalence about 89.1% and among them aac(6′)-Ib-cr was the most frequently detected [22]. In Hungary, prevalence of PMQR-positive Enterobacteriaceae isolated from urine clinical samples showed 17.7% [23]. In the past 8 years, incidence of PMQRs among ESBL-producing E. coli and K. pneumoniae from bloodstream infection increased in Hungary [24].…”