Central Bronchial Deformity in Pulmonary Sarcoidosis: A Finding Suggestive of an Upper Lobe Fibrotic Phenotype on Chest Images

RATIONALE AND OBJECTIVES:Bronchial and lung parenchymal structural remodeling may occur due to disease progression in patients with pulmonary sarcoidosis; however, its mechanisms remain unclear. Central bronchial deformity (CBD) associated with shrinkage in the upper lobe (SUL) is often observed in such patients. This study aimed to examine the association between CBD and structural remodeling to identify features indicating disease severity on chest images. MATERIALS AND METHODS:This retrospective cohort study included 72 patients with pulmonary sarcoidosis, excluding patients with only bilateral hilar lymphadenopathy. The participants were divided into with and without CBD groups to examine the association between CBD and other structural remodeling, including SUL, cyst and/or low attenuation area-like emphysema (Cyst/LAA), pleural/sub-pleural thickening (PT), and traction bronchiectasis (TrBE), in the upper lobe on chest images. The association of CBD phenotype with respiratory dysfunction was also examined. RESULTS:CBD was highly associated with SUL (81.4% vs. 8.9%), Cyst/LAA (44.4% vs. 6.7%), and PT (59.2% vs. 3.7%). The respective odds ratios in the univariable and multivariable analyses were as follows: SUL, 45.1 and 39.9; Cyst/LAA, 11.2 and 14.2; and PT, 64.0 and 68.7. TrBE was frequently associated with CBD (22.25% vs. 4.4%); the odds ratio was 6.14 in the univariable analysis. Furthermore, participants with CBD exhibited lower %FVC and %DLCO. CONCLUSION:CBD is significantly associated with lung remodeling (SUL, Cyst/LAA, TrBE, and PT) and respiratory dysfunction. CBD may be a crucial clinical phenotype to identify upper lobe fibrotic changes.