Does FESS alter the sinonasal microbiome

Introduction: Chronic rhinosinusitis is a common health problem.However few studies comparing pre and post-FESS microorganisms and efficacy of FESS are present.The present study aims to analyze the alteration in sinonasal microbiome in patients of chronic rhinosinusitis with and without nasal polyposis after functional endoscopic sinus surgery. Patients and Methods: The prospective observational study was conducted in the Department of Otorhinolaryngology and Head Neck Surgery, SRMS IMS from November 2017 to April 2019 after the approval by the Research/Ethics Committee. All patients clinically diagnosed as Chronic Rhinosinusitis (CRS) with and without Nasal Polyposis posted for Functional Endoscopic Sinus Surgery (FESS) formed the study group.Culture analysis of specimen from middle meatus region was done twice first, prior to FESS and second 6 weeks post-FESS.The changes in the microbiome were then analysed. Results: In 31.4% patients methicillin resistant staphylococcus aureus was cultured prior to FESS. Other organisms cultured were Staphylococcus aureus, Pseudomonas, Aspergillus, E.coli, Rhizopus and E.Faecalis. Post-FESS cultures were obtained at 6 weeks. Staphylococcus aureus was cultured in 77% cases. No fungal microbes or MRSA were cultured post operatively. In 11.4 % cultures no microorganisms were detected. No statistical correlation was observed between the diagnosis and organisms cultured. Conclusion: The preoperative culture of MRSA and its absence in post-FESS cultures points to role in the pathogenesis of CRS. Fungal organisms Aspergillus and Rhizopus were cultured pre-operatively which were present in combination with bacteria supporting the co-infection theory. Effective role of FESS as surgical management is also consolidated.