Memorias do Instituto Oswaldo Cruz (Aug 2012)

The first report of the qnrB19, qnrS1 and aac(6´)-Ib-cr genes in urinary isolates of ciprofloxacin-resistant Escherichia coli in Brazil

  • Magna Cristina Paiva,
  • Andréa Maria Amaral Nascimento,
  • Ilana Lopes Baratella Cunha Camargo,
  • Cláudia Iracema Lima-Bittencourt,
  • Regina Maria Drummond Nardi

DOI
https://doi.org/10.1590/S0074-02762012000500018
Journal volume & issue
Vol. 107, no. 5
pp. 687 – 689

Abstract

Read online

In this study, we investigated the presence of plasmid-mediated quinolone resistance (PMQR) genes among 101 ciprofloxacin-resistant urinary Escherichia coli isolates and searched for mutations in the quinolone-resistance-determining regions (QRDRs) of the DNA gyrase and topoisomerase IV genes in PMQR-carrying isolates. Eight isolates harboured the qnr and aac(6')-Ib-cr genes (3 qnrS1, 1 qnrB19 and 4 aac(6')-Ib-cr). A mutational analysis of the QRDRs in qnr and aac(6')-Ib-cr-positive isolates revealed mutations in gyrA, parC and parE that might be associated with high levels of resistance to quinolones. No mutation was detected in gyrB. Rare gyrA, parC and parE mutations were detected outside of the QRDRs. This is the first report of qnrB19, qnrS1 and aac(6')-Ib-cr -carrying E. coli isolates in Brazil.

Keywords