Prevalence of biofilms and their response to medical treatment in chronic rhinosinusitis without polyps.

OBJECTIVE: The aim of this study was to investigate the prevalence of biofilms and the effects of medical treatment modalities in chronic rhinosinusitis (CRS) patients without nasal polyps.

STUDY DESIGN: Randomized controlled trial.

SETTINGS: Tertiary referral hospital.

SUBJECTS AND METHODS: The authors randomly divided 32 adult patients with CRS without nasal polyps into 2 groups. In the first group (n = 16), oral clarithromycin was administered 500 mg/bid for 2 weeks and then 250 mg/d for the following 6 weeks. In the second group (n = 16), an 8-week course of 200-mcg/d topical mometasone furoate was added to the clarithromycin regimen, identical to the first group. The pre- and posttreatment nasal tissue samples were evaluated by scanning electron microscopy for biofilm prevalence and graded from 0 to 3 according to density and extension.

RESULTS: Biofilms were detected in 24 of 32 patients (75%) before the treatment (grades 1-3). Biofilms were detected in 14 of 32 patients (43.8%) after the treatment (grades 1-2). When each group was evaluated independently, there was a significant improvement after the treatment in both groups I and II. When the biofilm grades of group I were compared to those of group II, there was no significant difference both in the pre- and posttreatment evaluation.

CONCLUSION: The prevalence of biofilms in CRS without polyps was 75% in our study. Regression of biofilms to 43% was observed under medical treatment. Adding nasal steroids to macrolides gave no further benefit.