Association of plasmid-mediated quinolone resistance with extended-spectrum beta-lactamase VEB-1.

Association of the plasmid-mediated quinolone resistance determinant QnrA and the bla(VEB-1) gene was identified in a single Enterobacter cloacae isolate from K.-Bicêtre, France, and in 11 out of 23 bla(VEB-1)-positive enterobacterial isolates from Bangkok, Thailand. This result may explain in part the association between quinolone and extended-spectrum beta-lactam resistance.

Emergence of plasmid-mediated quinolone resistance in Escherichia coli in Europe.

Although quinolone resistance results mostly from chromosomal mutations, it may also be mediated by a plasmid-encoded qnr gene in members of the family Enterobacteriaceae. Thus, 297 nalidixic-acid resistant strains of 2,700 Escherichia coli strains that had been isolated at the Bicetre Hospital (Le Kremlin-Bicetre, France) in 2003 were screened for qnr by PCR. A single E.