Subclinical pulmonary abnormalities on chest CT in patients with eosinophilic chronic rhinosinusitis

BACKGROUND: Chronic rhinosinusitis (CRS) often coexists with lower respiratory tract diseases, and such cases tend to be more refractory. However, few studies have specifically investigated chest computed tomography (CT) findings in patients with CRS. This study analyzed chest CT findings in patients with CRS and investigated their associations with CRS phenotypes and clinical characteristics. METHODS: We retrospectively analyzed 278 patients with CRS who underwent preoperative chest CT prior to endoscopic sinus surgery. Patients were stratified based on the presence or absence of abnormal chest CT findings. Clinical parameters related to upper and lower airway inflammation, including CRS phenotypes, were compared between the groups. The prognosis for ECRS was evaluated using the systemic steroid dose as a longitudinal outcome variable in a linear mixed-effects model. RESULTS: Among the 278 patients, 174 were diagnosed with eosinophilic CRS (ECRS) and 104 with non-eosinophilic CRS (NECRS). Ground-glass attenuation (GGA) and bronchial wall thickening (BWT) were observed in 35 and 27 patients (12.6 %, 9.7 %), respectively. The frequencies of GGA and BWT were significantly higher in the ECRS group than in the NECRS group. Among patients with ECRS, those with GGA had significantly higher tissue eosinophil counts and Lund-Mackay CT scores, as well as significantly lower olfactory function. Steroid dose reduction was significantly slower in the GGA group. CONCLUSIONS: The presence of GGA on chest CT in patients with CRS is associated with the CRS phenotype and greater disease severity, suggesting that chest imaging findings could serve as potential indicators of systemic disease burden in CRS.