background :    klebsiella pneumoniae is among the most common and significant agents of community and hospital-acquired infections. plasmid mediated quinolone resistance (pmqr) was increasingly identified in enterobacteriaceae family worldwide. plasmid-mediated quinolone resistance (pmqr) was first reported in 1998 from a klebsiella pneumoniae isolate in the usa. till date, five qnr proteins h...

OBJECTIVES The aims of this study were to identify qnr genes among quinolone-resistant Escherichia coli isolates from defined disease conditions of companion and farm animals obtained in the BfT-GermVet study, and to gain insight into their localization and the organization of the qnr gene regions. METHODS The qnr genes were detected by PCR and confirmed by sequencing. qnr-positive isolates w...

background and aims: extended-spectrum β-lactamase (esbl) producing gram negative bacteria are resistant to penicillins, narrow and extended-spectrum cephalosporins, and aztreonam; also they are frequently resistant to trimethoprim-sulfamethoxazole, aminoglycosides, and quinolones. this study aimed to investigate the prevalence of plasmid-mediated quinolone resistance (pmqr) determinants qnra, ...

OBJECTIVES To characterize the prevalence of plasmid-mediated quinolone resistance determinants qnr and aac(6')-Ib-cr in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae. METHODS qnrA, qnrB, qnrS, aac(6')-Ib-cr and ESBL-encoding genes were detected by PCR. MICs of 10 antimicrobial agents were determined by Etest. PFGE was used to investigate the clo...

OBJECTIVES Plasmid-mediated quinolone resistance (PMQR) caused by qnr genes has been known for 15 years. Information about global distribution and prevalence of qnr genes is abundant, but clinical information concerning infections produced by these isolates and risk factors for their acquisition is limited. METHODS Klebsiella pneumoniae blood isolates (n = 227) from a 1 year prospective cohor...

OBJECTIVES The aim of this study was to determine the spread of plasmid-mediated quinolone resistance determinants [qnr-like, aac(6')-Ib-cr and qepA genes] among nalidixic acid-resistant enterobacterial strains isolated from outpatients from Southeast Brazil, their transferability and the genetic structures associated with the qnr genes. METHODS The qnrA, qnrB and qnrS genes were screened by ...

Sir, Currently, a variety of qnrA, B and S genes are commonly isolated from clinically important Enterobacteriaceae. Moreover, qnr genes have been detected in non-typhi Salmonella enterica serotypes in Europe, the United States, Africa, Australia and Asia. In a recent study, the presence of qnrA1 in the Netherlands was first detected in a multidrug-resistant Enterobacter cloacae carrying a conj...

conclusions ctx-m was the most prevalent esbl genotype in uropathogenic e. coli (upec) isolated from uti. in addition, a high frequency of qnr genes among esbl-producing e. coli was identified in this study. in order to avoid treatment failures, we recommend using phenotypic and molecular methods to diagnose these enzymes and qnr genes. results the highest sensitivity was seen to imipenem (96.7...

INTRODUCTION Although independently acquired, plasmid-mediated quinolone resistance appears to be linked with extended-spectrum or AmpC-type beta-lactamases. Since no data are available in African countries, the prevalence of qnr genes at the University Hospital Ibn Rochd, Casablanca, Morocco, was investigated. METHODOLOGY Between October 2006 and March 2007, the following 39 randomly selecte...

background plasmid-mediated quinolone resistance genes (pmqr) have been shown to play not only an important role in quinolone resistance, but also resistance to other antibiotics, particularly β-lactams and aminoglycosides. these genes are mainly associated with clinical isolates of enterobacteriaceae. however, detection of pmqr genes in the community isolates can increase the dissemination rat...