Do high-resolution CT findings of usual interstitial pneumonitis obviate lung biopsy? Views of pulmonologists

Background: High-resolution CT (HRCT) of the lungs has become an essential component to evaluate patients with diffuse lung disease. Little is known, however, about the current practices of pulmonologists caring for patients with these complex conditions, and, in particular, whether HRCT can obviate the need for surgical lung biopsy. Objectives: To investigate the practices of pulmonologists concerning the acceptability of a HRCT diagnosis in lieu of lung biopsy in diffuse lung disease. Methods: We asked practicing pulmonologists among membership of the American College of Chest Physicians whether HRCT results could replace lung biopsy in 16 diffuse lung diseases. Responses were examined in light of published evidence, practice guidelines, and certain practice parameters. Results: Two hundred and thirty (52.6%) of 437 eligible physicians responded. Sixty-seven percent (67%) of respondents accepted HRCT diagnosis for idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP) despite their awareness of guidelines recommending histological diagnosis. Most would not accept a radiologic diagnosis for lymphangioleiomyomatosis (LAM; 37%) or eosinophilic granuloma (Langerhans' cell histiocytosis, LCH; 19%), even though CT findings are frequently characteristic. Responses were similar by type of clinical practice and recency of fellowship training. Chest physicians who referred patients for HRCT more frequently were more likely to accept HRCT diagnosis (p = 0.008) and those who had higher self-ratings of proficiency in reading HRCT (p = 0.004) were more likely to believe HRCT often suggests specific diagnosis. Conclusions: Most US pulmonologists will accept an HRCT diagnosis of IPF/UIP without lung biopsy, but are reluctant to do so for most other diffuse lung conditions including LAM and LCH.