Persistent discharge or edema after endoscopic sinus surgery in patients with chronic rhinosinusitis is associated with a type 1 or 3 endotype

BACKGROUND: Patients with chronic rhinosinusitis (CRS) may have persistence of polyps, discharge, or edema after endoscopic sinus surgery (ESS). Inflammation in CRS can be classified into three endotypes, with the presence of polyps associated with the type 2 endotype. Here, we evaluate the endotypic underpinnings of discharge or edema without polyps after ESS. METHODS: At a visit 6–12 months post ESS, patients underwent endoscopy and completed the CRS‐PRO and SNOT‐22. Luminex analysis of middle meatal mucus obtained at that visit was performed for IFN‐γ, ECP, and IL‐17a. Type 1, 2, and 3 endotypes were defined as greater than the 90th percentile expression of each marker, respectively, in controls. Wilcoxon rank‐sum and chi‐squared tests were used to compare cytokine levels and endotype prevalence between those with and without endoscopic findings. RESULTS: A total of 122 CRS patients completed a clinical exam (median: 8.2 months post ESS). Of the 122 patients, 107 did not have polyps on endoscopy. Of these 107 patients, 48 had discharge, 44 had edema, and 46 had neither discharge nor edema. Compared with those patients without any findings, patients with discharge or edema reported significantly worse severity as measured by CRS‐PRO (10.5 vs. 7.0, p = 0.009; 12.0 vs. 7.0, p < 0.001; respectively), and had higher post‐ESS IFN‐γ, ECP, and IL‐17a. Patients with discharge had higher prevalence of only T1 and T3 endotypes, while patients with edema had higher prevalence of only the T3 endotype. CONCLUSIONS: Post‐ESS discharge or edema in the absence of polyps was associated with higher patient‐reported outcome severity and was more strongly associated with type 1 or 3 inflammation.