Background: Pseudomonas aeruginosa is cultured in nearly 1 of 5 patients with chronic rhinosinusitis and a history of sinus surgery. Fluoroquinolones are the only enterally administered antibiotics with efficacy against P. aeruginosa, but their frequent empiric use in the community raises concern for a rise in resistance.
Objective: It was the aim of this study to determine the prevalence of fluoroquinolone-resistant P. aeruginosa in a tertiary rhinology practice.
Methods: All bacterial sinus culture results from the outpatient otolaryngology clinic that yielded P. aeruginosa over a 5-year period (2002-2007) were reviewed along with the medical records of a randomly selected subset of patients.
Results: In total, 689 culture results of 324 patients were examined. Nearly all patients had a history of endoscopic sinus surgery. Of all P. aeruginosa cultured, 13% were resistant to levofloxacin and 5% were intermediately sensitive, while 5% were resistant to ciprofloxacin and 7% intermediately sensitive. Of the 324 patients in the study, 19 and 15% had a history of a P. aeruginosa culture resistant to levofloxacin or ciprofloxacin, respectively. Mucoid strains of P. aeruginosa were significantly more likely to be fluoroquinolone resistant. No patient comorbidities were associated with a higher rate of resistance. The prevalence of resistant cultures remained stable over the 5-year study period.
Conclusions: P. aeruginosa is cultured primarily in patients with previous sinus surgery. Nearly 20% of isolates are resistant to fluoroquinolones. Resistance to levofloxacin is more common than resistance to ciprofloxacin. This study supports the use of culture-directed therapy in the management of the postfunctional endoscopic sinus surgery patient and the avoidance of empiric use of fluoroquinolones.
Copyright 2009 S. Karger AG, Basel.