Bacterial biofilm evidence in nasal polyposis

Abstract

The pathogeny of chronic rhinosinusitis with nasal polyposis (CRS/NP) has not been elucidated. Bacterial exotoxins have beenimplicated in many infl ammatory chronic diseases, such as chronic otitis, chronic tonsillitis, cholesteatomas, and more recently CRS/NP. Wepropose that the bacteria in CRS/NP are not only present in a planktonic state, but also occur in microbial communities as biofi lms.Objective: To determine and characterize the presence of biofi lms in CRS/NP.Methods: We performed a prospective study in 12 patients undergoing endoscopic sinus surgery for nasal polyposis. Ten patients withoutCRS/NP who underwent septoplasty were included as a control group. Tissue samples were obtained from the inferior turbinate mucosae.The bacteria were isolated and typifi ed and the material was examined in vitro using a spectrophotometer, and in vivo using opticalmicroscopy and confocal scanning laser microscopy.Results: Moderate to high in vitro biofi lm-forming capacity was detected in 9 out of 12 patients with CRS/NP (mean [SD] optical densityvalues of between 0.284 [0.017] and 3.337 [0.029]). The microorganisms isolated were Staphylococcus (5 patients), Streptococcus viridans,Pseudomonas aeruginosa, Enterococcus faecalis and Streptococcus viridans/Corynebacterium. Biofi lms were demonstrated in vivo in 2 patientsand no biofi lm structures were evident in any of the controls.Conclusion: This study demonstrates the presence of bacterial biofi lms in patients with CRS/NP. This chronic infl ammatory factor mightcontribute to nasal mucosa damage, increased infl ammatory cells in tissue, and the subsequent hyperplasic process