We determined the prevalence of plasmid-mediated quinolone resistance mechanisms among non-Typhi Salmonella spp. isolated from humans, food animals, and retail meat in the United States in 2007. Six isolates collected from humans harbored aac(6')Ib-cr or a qnr gene. Most prevalent was qnrS1. No animal or retail meat isolates harbored a plasmid-mediated mechanism.

The gene qnr (qnrA [G. A. Jacoby, K. Walsh, D. Mills, V. Walker, A. Robicsek, H. Oh, and D. C. Hooper, Abstr. 44th Intersci. Conf. Antimicrob. Agents Chemother., abstr. C2-1898a, 2004]; encoding QnrA) was first identified as a transferable quinolone resistance determinant on a multidrug-resistant plasmid in Klebsiella pneumoniae (6, 9) and has been detected in K. pneumoniae, Escherichia coli, E...

OBJECTIVES A burn unit of a hospital in Tunis underwent an endemic situation caused by imipenem-resistant Pseudomonas aeruginosa. For nine non-repetitive isolates of a clonal VIM-2-producing strain, the blaVIM-2 genetic background was characterized and the associated qnrVC1 gene molecularly analysed. METHODS The imipenem resistance mechanism was investigated by phenotypic and molecular tests,...

OBJECTIVES To analyse the prevalence of resistance to β-lactams and plasmid-mediated quinolone resistance in Enterobacteriaceae in the paediatric hospital of Uruguay. METHODS A total of 368 enterobacterial isolates collected between 1 May and 30 November 2009 were studied for the presence of extended-spectrum β-lactamases (ESBLs), qnr alleles and aac(6')Ib by phenotypic and molecular methods....

OBJECTIVES The aim of this study was to determine the occurrence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli at an equine clinic and a horseback riding centre, and to discuss the impact of antimicrobial treatment on resistance selection. METHODS Faeces from horses, environmental smears and flies were sampled at both the clinic and riding centre. Staff at the equine clin...

Quinolone antibiotics have been commonly used to treat cases of multiple antibiotic resistance. Unfortunately, quinolone so much resisted by infectious bacterial agents. This study aimed evaluate the susceptibility some clinical isolates E. coli and determination plasmid-encoded resistance genes.
 Our results showed plasmid quinolone-resistance genes in following prevalence: qnr genes: S (...

BACKGROUND Salmonella and Shigella cause significant morbidity and mortality among children worldwide. Increased antimicrobial resistance results in greater burden of disease. MATERIALS AND METHODS From 2005 to 2011, Salmonella and Shigella isolates collected from ill children at a major hospital in Yucatan, Mexico, were subjected to serotyping and antimicrobial susceptibility testing by disk...