Transbronchial biopsy in usual interstitial pneumonia

Background: Usual interstitial pneumonia (UIP) is a slowly progressive, usually fatal form of idiopathic interstitial pneumonia for which there is no effective treatment. Transbronchial biopsy (TBB) has been utilized only to exclude other diseases such as sarcoidosis, lymphangitic carcinoma, and infection, for example, but TBB is generally considered to have little role in confirming UIP. Objective: To determine whether diagnostic changes of UIP can be appreciated on TBB specimens. Design: Retrospective analysis of TBB specimens from patients with proven UIP. Setting: Two study sites in the United States. Participants: Twenty-one patients with UIP confirmed by surgical lung biopsy and/or lung explant, and 1 patient with UIP confirmed by clinical and radiographic findings along with follow-up information. Measurements and results: Adequate tissue for diagnosis was available in IS cases; in 7 cases (32% overall), there were varying combinations of interstitial fibrosis in a patchwork pattern along with fibroblast foci and/or honeycomb change. These features were considered diagnostic of UIP. Interstitial fibrosis along with fibroblast foci or honeycomb change were seen in two other cases, but the fibrosis lacked a patchwork pattern, and these features were considered consistent with UIP. Nonspecific interstitial fibrosis alone was found in nine cases. Conclusions: In summary, characteristic histologic features of UIP can be identified on TBB specimens more often than previously appreciated. TBB may be more useful in confirming UIP than previously recognized.