Coexistence of plasmid-mediated quinolone resistance determinants and AmpC-Beta-Lactamases in Escherichia coli strains in Egypt

摘要

Three kinds of plasmid-mediated quinolone resistance (PMQR) determinants (qnr genes, qepA and aac(6')-Ib-cr) have been discovered and shown to be widely distributed among clinical isolates. To characterize the prevalence of PMQR determinants among AmpC-producing E. coli strains in food-producing animals and animal by-products in Egypt, twenty-nine E. coli strains were tested for their susceptibilities to antimicrobials and screened for PMQR determinants and AmpC Beta lacta-mases using PCR and plasmid profiling. It was found that qnr genes being detected alone or in combination with qepA or aac(6')-Ib-cr genes in 11 (37.9%) strains comprising 9 for qnrA and only one for both qnrB and qnrS. Moreover, qepA and aac(6')-Ib-cr were detected in 41.38% and 3.45% of E. coli strains, respectively. The ampC beta-lactamase genes were detected in 75.86 % of all strains and in 100% and 53.3% of the PMQR determinant-positive and negative strains, respectively. In several cases, plasmid profiling of E. coli strains exhibiting the coexistence of both PMQR determinants and ampC genes on a single plasmid as a first report in Egypt that may contribute to rapid spread and increase in bacterial resistance, which is important to public health concern.