REVIEWNeutrophilic inflammation in chronic rhinosinusitisDelemarre, Tima; Bachert, Clausa,b,c Author Information aUpper Airways Research Laboratory, Faculty of Medicine, Ghent University, Ghent, Belgium bDivision of ENT Diseases, CLINTEC, Karolinska Institute, Stockholm, Sweden cFirst Affiliated Hospital, Sun Yat-Sen University, International Airway Research Center, Guangzhou, China Correspondence to Claus Bachert, MD, PhD, Upper Airways Research Laboratory, Department Head & Skin, Ghent University, UZ Ghent, C. Heymanslaan 10, 9000 Ghent, Belgium. Tel: +32 9 332 2363; e-mail: [email protected] Current Opinion in Allergy and Clinical Immunology: November 03, 2022 - Volume - Issue - 10.1097/ACI.0000000000000868 doi: 10.1097/ACI.0000000000000868 Buy PAP Metrics Abstract Purpose of review Over the last years, extensive research has been done on neutrophils and their contribution in chronic rhinosinusitis (CRS), and made it clear that they are more than just a bystander in this disease. In this article, we will review all recent publications on this topic and look to what the future hold regarding therapeutics targeting the neutrophilic inflammation in CRS. Recent findings Evidence is growing that the presence of neutrophils are associated with a worse disease outcome in certain CRS patient groups. They are highly activated in type 2 inflammations and exhibit damaging properties through their proteases, contributing to the chronicity of the disease. Several recent studies identified useful biomarkers and targets for future therapeutics. Summary The findings we review in this manuscript are of utmost importance in unraveling the complexity of CRS and provide us with the necessary knowledge for future clinical practices. Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.