Contributing Authors: Isam Alobid, MD, PhD¹, Nithin D. Adappa, MD², Henry P. Barham, MD³, Thiago Bezerra, MD⁴, Nadieska Caballero, MD⁵, Eugene G. Chang, MD⁶, Gaurav Chawdhary, MD⁷, Philip Chen, MD⁸, John P. Dahl, MD, PhD⁹, Anthony Del Signore, MD¹⁰, Carrie Flanagan, MD¹¹, Daniel N. Frank, PhD¹², Kai Fruth, MD, PhD¹³, Anne Getz, MD¹⁴, Samuel Greig, MD¹⁵, Elisa A. Illing, MD¹⁶, David W. Jang, MD¹⁷, Yong Gi Jung, MD¹⁸, Sammy Khalili, MD, MSc¹⁹, Cristobal Langdon, MD²⁰, Kent Lam, MD²¹, Stella Lee, MD²², Seth Lieberman, MD²³, Patricia Loftus, MD²⁴, Luis Macias‐Valle, MD²⁵, R. Peter Manes, MD²⁶, Jill Mazza, MD²⁷, Leandra Mfuna, MD²⁸, David Morrissey, MD²⁹, Sue Jean Mun, MD³⁰, Jonathan B. Overdevest, MD, PhD³¹, Jayant M. Pinto, MD³², Jain Ravi, MD³³, Douglas Reh, MD³⁴, Peta L. Sacks, MD³⁵, Michael H. Saste, MD³⁶, John Schneider, MD, MA³⁷, Ahmad R. Sedaghat, MD, PhD³⁸, Zachary M. Soler, MD³⁹, Neville Teo, MD⁴⁰, Kota Wada, MD⁴¹, Kevin Welch, MD⁴², Troy D. Woodard, MD⁴³, Alan Workman⁴⁴, Yi Chen Zhao, MD⁴⁵, David Zopf, MD⁴⁶Contributing Author Affiliations: ¹Universidad de Barcelona; ²University of Pennsylvania; ³Louisiana State University Health Sciences Center; ⁴Universidade de São Paulo; ⁵ENT Specialists of Illinois; ⁶University of Arizona; ⁷University of Oxford; ⁸University of Texas; ⁹University of Indiana; ¹⁰Mount Sinai Beth Israel; ¹¹Emory University; ¹²University of Colorado; ¹³Wiesbaden, Germany; ¹⁴University of Colorado; ¹⁵University of Alberta; ¹⁶University of Alabama at Birmingham; ¹⁷Duke University; ¹⁸Sungkyunkwan University; ¹⁹University of Pennsylvania; ²⁰Universidad de Barcelona; ²¹Northwestern University; ²²University of Pittsburgh; ²³New York University; ²⁴Emory University; ²⁵University of British Columbia; ²⁶Yale University School of Medicine; ²⁷Private Practice; ²⁸Department of Otolaryngology, Hôtel‐Dieu Hospital, Centre de Recherche du Centre Hospitalier de l'Université de Montréal; ²⁹University of Adelaide; ³⁰Pusan National University; ³¹University of California, San Francisco; ³²University of Chicago; ³³University of Auckland; ³⁴Johns Hopkins University; ³⁵University of New South Wales, Australia; ³⁶Stanford University; ³⁷Washington University; ³⁸Harvard Medical School; ³⁹Medical University of South Carolina; ⁴⁰Singapore General Hospital; ⁴¹Taho University; ⁴²Northwestern University; ⁴³Cleveland Clinic Foundation; ⁴⁴University of Pennsylvania; ⁴⁵University of Adelaide; ⁴⁶University of Michigan

Background: 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. Methods: 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. Results: 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. Conclusion: 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.

Background: Conclusive evidence exists that biofilms are present on the mucosa of chronic rhinosinusitis (CRS) patients. Less is known about the species constituting these biofilms. This study developed a fluorescence in situ hybridization (FISH) protocol for characterization of bacterial and fungal biofilms in CRS. Methods: Fifty CRS patients and 10 controls were recruited. Bacteria FISH probes for Staphylococcus aureus, Haemophilus influenzae, and Pseudomonas aeruginosa and a universal probe for fungi were applied to sinus mucosal specimens and then analyzed using confocal scanning laser microscopy. Results: Thirty-six of 50 CRS patients had biofilms present in contrast to 0/10 controls, suggesting a role for biofilms in the pathogenesis of this disease. S. aureus was the most common biofilm-forming organism. Eleven of 50 CRS patients had characteristic fungal biofilms present. Conclusion: This is the largest study of biofilms in CRS. It has validated mucosal tissue cryopreservation for delayed biofilm analysis. Fungal biofilms have been identified and the importance of S. aureus biofilms in the polymicrobial etiology of CRS is highlighted.