Immunological mechanisms and treatable traits of chronic rhinosinusitis in Asia: A narrative review

To review the current literature on immunological mechanisms and treatable traits of chronic rhinosinusitis (CRS) in Asia.This is a narrative review of published data on the immunological mechanisms and treatable traits of CRS in Asia. Published English literature on CRS in Asian and Western countries was reviewed. Where available, the data extracted included epidemiology, immunology, bacterium, phenotype, endotype and treatment.CRS is a heterogeneous disease characterised by persistent locoregional mucosal inflammation of the paranasal sinuses. The inflammatory signatures of CRS vary across patients with distinct racial and ethnic backgrounds and geographic areas. Compared to CRS patients in Western countries, Asian CRS patients display less eosinophilic and Type 2 inflammation, which is associated with lower asthma and allergic rhinitis comorbidities. In contrast, Asian patients with CRS have more prominent non-eosinophilic inflammation than those in Western countries. In addition, Asian CRS patients may have different bacterial colonisation than patients in Western countries. Our review suggests that the distinct immunological mechanisms between Asian and Western CRS patients may influence the clinical phenotype, responses to treatment and outcomes. The treatable trait is a new strategy and therapeutic target identified by phenotype or endotype and has been proposed as a new paradigm for the management of diseases. Improved understanding of CRS phenotypic and endotypic heterogeneity and incorporation of treatable traits into clinical care pathways may facilitate more effective selections of therapeutic interventions, including surgery and biologics.