Endotypes of Chronic Rhinosinusitis Across Ancestry and Geographic Regions

Purpose of ReviewPreliminary studies have suggested differences in endotypes of chronic rhinosinusitis (CRS) across ancestry/ethnic groups. Eosinophilic CRS (ECRS) is the predominant subtype for Western/European ancestry CRS patients and non-eosinophilic CRS (nECRS) for Asian patients. This review aims to re-analyze CRS endotypes across ancestry populations using one consistent criteria to existing data.Recent FindingsAlthough tissue eosinophilia is the most commonly used criterion for ECRS, various cut-off points are suggested. Surrogate markers have been extensively studied. Sixty-six cohorts with study criteria were included with a total of 8557 patients. Raw data from 11 studies 544 patients were re-analyzed using number of tissue eosinophils. At lower cut-off values of ≥ 5 and ≥ 10 cells/HPF, most patients of Asian and Western/European ancestry were classified as ECRS without difference. In contrast, at cut-off points of ≥ 70 and ≥ 120 cells/HPF, the majority of both groups became reclassified as nECRS.SummaryAfter applying one consistent criteria to existing data, differences across ancestry and geographic populations in endotypes of CRS were no longer evident.