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Fluoroquinolone-resistant Pseudomonas aeruginosa in chronic rhinosinusitis

Joel Guss1, W M Abuzeid, Laurel Doghramji

  • 1Department of Otorhinolaryngology, Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA, USA.

ORL; Journal for Oto-Rhino-Laryngology and Its Related Specialties
|October 3, 2009
PubMed
Abstract

Insights

Fluoroquinolone resistance in Pseudomonas aeruginosa is common in patients with chronic rhinosinusitis and prior sinus surgery. Nearly 20% of isolates show resistance, supporting culture-directed therapy over empiric antibiotic use.

Area of Science:

  • Otolaryngology
  • Infectious Diseases
  • Microbiology

Background:

  • Pseudomonas aeruginosa is frequently found in chronic rhinosinusitis patients with a history of sinus surgery.
  • Fluoroquinolones are the primary oral antibiotics effective against P. aeruginosa.
  • Rising fluoroquinolone resistance due to community use is a growing concern.

Purpose of the Study:

  • To determine the prevalence of fluoroquinolone-resistant P. aeruginosa in a tertiary rhinology practice.
  • To assess resistance patterns to levofloxacin and ciprofloxacin.

Main Methods:

  • Retrospective review of bacterial sinus culture results yielding P. aeruginosa from 2002-2007.
  • Inclusion of medical records for a subset of patients.
  • Analysis of 689 cultures from 324 patients, predominantly those with prior endoscopic sinus surgery.

Main Results:

  • 13% of P. aeruginosa isolates were resistant to levofloxacin; 5% were intermediately sensitive.
  • 5% of isolates were resistant to ciprofloxacin; 7% were intermediately sensitive.
  • Mucoid P. aeruginosa strains showed significantly higher fluoroquinolone resistance. Resistance prevalence remained stable over five years.

Conclusions:

  • P. aeruginosa is predominantly cultured in patients with a history of sinus surgery.
  • Approximately 20% of P. aeruginosa isolates exhibit fluoroquinolone resistance.
  • Levofloxacin resistance is more prevalent than ciprofloxacin resistance, advocating for culture-directed treatment.

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