Purpose of review: Bronchial and bronchiolar abnormalities in interstitial lung diseases (ILDs) are an issue often underestimated. However, new interstitial patterns with bronchiolar involvement are being described and the concept is still evolving. The scope of this review is to introduce a comprehensive approach to airway disorders in the context of ILDs, mainly from a pathologic perspective.
Recent findings: Recent studies have revealed significant inflammatory and structural alterations at the level of small airways in idiopathic interstitial pneumonias, which may participate in the lung-remodeling pathogenetic process. A suggested pathogenetic role of cigarette smoking for lung-remodeling in smoking-related ILDs is further investigated, and unclassified fibrosis as a prominent feature in lung biopsy specimens of smokers has been established. New targeted therapies for lymphangioleiomyomatosis based on molecular and biologic properties of the disease are currently undergoing clinical trials. Combined pharmaceutical and interventional therapeutic regimens are of growing concern for refractory airway lesions in sarcoidosis. The application of volumetric high-resolution computed tomography (HRCT) chest scanning with acquisition of expiratory images provides valuable information about the involvement of small airways in ILDs.
Summary: The imaging and pathologic focus on airway abnormalities in ILDs make them an integral part of their pathology with a significant pathogenetic role in interstitial processes and variable contribution to the functional status of patients.