Different biofilms, different disease? A clinical outcomes study.

OBJECTIVES/HYPOTHESIS A potential role for biofilms in Chronic Rhinosinusitis (CRS) has been proposed, and the adverse impact they have on disease severity and postoperative outcomes has also been well described. Recent advances have allowed the species within the biofilms of CRS patients to be clearly characterized. This study investigates whether different biofilm species have different disease outcomes. STUDY DESIGN Retrospective review. METHODS Twenty-four patients with medically recalcitrant CRS undergoing Endoscopic Sinus Surgery (ESS), in whom we had previously characterized their biofilms using fluorescence in situ hybridization (FISH), were reviewed a median of 11 months after their surgery. They were evaluated for preoperative disease markers and evidence of on-going disease in the postoperative period. RESULTS Thirty-seven biofilms were identified in the 24 patients. Almost half had polymicrobial biofilms. The presence of polymicrobial, rather than single-species biofilms adversely affected preoperative disease severity but did not alter postsurgical outcome. Patients with single organism Haemophilus influenzae biofilms presented with mild disease symptomatically and radiologically and achieved normal mucosa a short time after their surgery. Conversely, patients with Staphlococcus aureus in their biofilm makeup had more severe disease and a more complicated postoperative course. The effect of Pseudomonas aeruginosa and fungal biofilms is less clear. CONCLUSIONS Different biofilm species are associated with different disease phenotypes. H. influenzae biofilms are typically found in patients with mild disease, whereas S. aureus is associated with a more severe, surgically recalcitrant pattern.