The effect of bacterial biofilms on post-sinus surgical outcomes

Although the existence of biofilms on the sinus mucosa of patients with chronic rhinosinusitis (CRS) is now well established, the role that these structures play remains unclear. It is thought that biofilms may contribute to the recalcitrant and persistent nature that characterizes CRS, but little research exists documenting the effect that they have on postoperative mucosal outcomes. This article presents a retrospective analysis of sinus surgical patients and correlates the presence of biofilms with mucosal outcomes. This study was performed to evaluate the role that bacterial biofilms have on post-sinus surgical outcomes. A retrospective analysis of prospectively collected data was performed on 40 patients undergoing endoscopic sinus surgery (ESS) for CRS. Preoperative demographic, clinical, and radiologic data were recorded from each patient and, intraoperatively, sinus culture specimens and mucosal samples were obtained for microbiological and microscopic examination. Biofilm determination was performed using confocal scanning laser microscopy. Postoperatively, patients were followed up for a minimum of 8 months with endoscopic evaluation of their sinonasal mucosa. The presence of ongoing symptoms was recorded also. Bacterial biofilms were found in 20 (50%) of the 40 CRS patients. Patients with biofilms had significantly worse preoperative radiological scores and, postoperatively, had statistically worse postoperative symptoms and mucosal outcomes. The only other factor that was statistically related to an unfavorable outcome was the presence of fungus at the time of surgery. In this study the presence of polyps, eosinophilic mucin, or pus was not related to poor outcomes. This retrospective study showed that bacterial biofilms and fungus were correlated with the persistence of postoperative symptoms and mucosal inflammation after sinus surgery for CRS. This provides evidence that biofilms indeed may play an active role in perpetuating inflammation in CRS patients and may explain the recurrent and resistant nature of this disease. Therapies targeted at removing biofilms may be important in the management of recalcitrant CRS.