Experimental and clinical studies on fluoroquinolone-insusceptible Escherichia coli isolated from patients with urinary tract infections from 1994 to 2007

Koichiro Wada, Reiko Kariyama, Ritsuko Mitsuhata, Shinya Uehara, Toyohiko Watanabe, Koichi Monden, Hiromi Kumon

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Urinary tract infections (UTIs) due to fluoroquinolone-insusceptible Escherichia coli have become increasingly common in recent years. We investigated the potential relationships between clinical measures to combat fluoroquinolone-insusceptible E. coli and experimental analyses on E. coli isolates. Over a 14-year period from 1994 through 2007, a total of 828 E. coli isolates were collected from patients (one isolate per patient) with UTI at the urology ward of Okayama University Hospital. We analyzed the mutations in quinolone resistance-determining regions of DNA gyrase (gyrA) and topoisomerase IV (iparC). The production of biofllm by these isolates was also examined and the associated medical records were retrospectively reviewed. Seven of 189 (3.7%) strains from uncomplicated UTIs and 82 of 639 (12.8%) strains from complicated UTIs were insusceptible to fluoroquinolones. Amino acid replacements of type II topoisomerases were frequently observed at positions 83 and 87 in GyrA and at positions 80 and 84 in ParC. No significant difference in the biofilm-forming capabilities was observed between fluoroquinolone-susceptible and -insusceptible E. coli. Our study suggests that biofilm formation of fluoroquinolone-insusceptible E. coli isolates is not a major mechanism of resistance in patients with UTI.

Original languageEnglish
Pages (from-to)263-272
Number of pages10
JournalActa medica Okayama
Volume63
Issue number5
Publication statusPublished - Nov 2009

Keywords

  • Biofilm
  • Escherichia coli
  • Fluoroquinolone
  • MICs
  • QRDRs

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'Experimental and clinical studies on fluoroquinolone-insusceptible Escherichia coli isolated from patients with urinary tract infections from 1994 to 2007'. Together they form a unique fingerprint.

  • Cite this