Quinolone-resistant Haemophilus Influenzae in a Long-Term-Care Facility: Nucleotide Sequence Characterization of Alterations in the Genes Encoding DNA Gyrase and DNA Topoisomerase IV

Antimicrob Agents Chemother. 2004 Sep;48(9):3570-2. doi: 10.1128/AAC.48.9.3570-3572.2004.


Fluoroquinolone-resistant isolates of Haemophilus influenzae, obtained from a long-term care facility, were examined for nucleotide sequence differences in the quinolone-resistance-determining regions of gyrA, gyrB, parC, and parE. Similarities among the resistant isolates, plus multiple differences with susceptible isolates, suggest clonal dissemination involving two resistant subclones.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • DNA Gyrase / biosynthesis
  • DNA Gyrase / genetics*
  • DNA Topoisomerase IV / biosynthesis
  • DNA Topoisomerase IV / genetics*
  • Drug Resistance, Bacterial
  • Fluoroquinolones / pharmacology*
  • Genes, Bacterial
  • Haemophilus influenzae / drug effects*
  • Humans
  • Microbial Sensitivity Tests
  • Skilled Nursing Facilities*


  • Anti-Bacterial Agents
  • Fluoroquinolones
  • DNA Topoisomerase IV
  • DNA Gyrase