CT-Based Osteitis Severity for Identifying Eosinophilic Endotype in Chronic Rhinosinusitis With Nasal Polyps.

OBJECTIVE: To determine whether computed tomography-based osteitis severity reflects the eosinophilic endotype and to compare its discriminatory performance with conventional mucosal radiologic scoring. STUDY DESIGN: Prospective cohort study. SETTING: A tertiary referral otolaryngology hospital in Ho Chi Minh City, Vietnam. METHODS: A total of 154 patients with chronic rhinosinusitis with nasal polyps were prospectively included. Osteitis severity was assessed using the Kennedy Osteitis Score. Tissue eosinophil density was quantified histopathologically, and eosinophilic endotype was defined as ≥10 eosinophils per high-power field. Associations were analyzed using Spearman correlation and multivariable regression. Receiver operating characteristic analysis evaluated the ability of this score and Lund-Mackay score to identify eosinophilic disease. RESULTS: Osteitis severity correlated with tissue eosinophil density (rs = 0.45, P < .001) and Lund-Mackay score (rs = 0.42, P < .001). In multivariable analysis, tissue eosinophils (β = 0.31, P < .001) and Lund-Mackay score (β = 0.31, P < .001) remained independently associated with osteitis severity. Receiver Operating Characteristic analysis showed good discrimination of eosinophilic endotype by Kennedy Osteitis Score (AUC = 0.777), outperforming Lund-Mackay score (AUC = 0.661). A threshold ≥1 yielded 69.6% sensitivity and 83.3% specificity. CONCLUSIONS: Computed tomography-based osteitis severity reflects tissue eosinophilia and outperforms conventional mucosal radiologic scoring, supporting its potential as a noninvasive imaging marker for preoperative endotype stratification.