Bacterial biofilms in chronic rhinosinusitis.

Chronic sinusitis is a prevalent, debilitating condition, and a subpopulation of patients fails to respond to either medical or surgical intervention. Bacterial biofilms are 3-dimensional aggregates of bacteria that have special properties due to their group structure, including increased resistance to antibiotics in some forms. They have been shown to play a major role in many chronic infections, including cystic fibrosis, endocarditis, and otitis media. Evidence now suggests that they may play an important role in chronic sinusitis. Our laboratory has identified the presence of biofilms in sinonasal mucosa isolated from human patients and on stents removed after frontal sinus surgery. In addition, biofilms have been found on the sinus epithelium of rabbits infected with Pseudomonas aeruginosa, but not in rabbits infected with non-biofilm-forming P. aeruginosa mutants. This animal model can provide opportunities to address the functional significance of biofilm production in the sinus cavities. A further understanding of the role of bacterial biofilms may lead to the development of more appropriate therapies for the treatment and prevention of chronic sinusitis.