title: Distinct immunologic and radiographic patterns in etanercept-induced lung injury.
abstract: Nonspecific clinical presentation of non-infectious, immune-mediated pulmonary complications of etanercept therapy makes the diagnosis difficult. While bronchoalveolar lavage fluid (BALF) cell analysis is frequently used in diagnosing drug-induced lung disease, BALF patterns in etanercept-induced lung injury (EILI) are not well established. Furthermore, previous reports of EILI diagnosis relied on transbronchial or surgical lung biopsies. Here, we report two patients who developed pulmonary toxicity after etanercept treatment. Both patients were diagnosed with EILI. While one patient presented with CD4(+)-predominant lymphocytic alveolitis (consistent with a sarcoid-like pattern), the other patient exhibited a CD8(+)-predominant pattern (consistent with hypersensitivity pneumonitis-like reaction). The different BAL patterns were accompanied by distinct radiographic findings. Both patients significantly improved after etanercept discontinuation and corticosteroid initiation. We propose that EILI can present with distinct immunologic and radiographic phenotypes. In addition, early BALF analysis with lymphocyte immunophenotyping can further define the underlying immunologic abnormalities, and thereby, avoid more invasive procedures.
authors.affiliation: Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Occupational Medicine, Indiana University School of Medicine, 1481 W. 10th Street, VA 111P-IU, Indianapolis, IN 46202, USA.
authors.forename: Karina
authors.initials: K
authors.lastname: Serban
authors.affiliation: Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Occupational Medicine, Indiana University School of Medicine, 1481 W. 10th Street, VA 111P-IU, Indianapolis, IN 46202, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Muzoora
authors.affiliation: Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Occupational Medicine, Indiana University School of Medicine, 1481 W. 10th Street, VA 111P-IU, Indianapolis, IN 46202, USA.
authors.forename: Chadi A
authors.initials: CA
authors.lastname: Hage
authors.affiliation: Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Occupational Medicine, Indiana University School of Medicine, 1481 W. 10th Street, VA 111P-IU, Indianapolis, IN 46202, USA ; Roudebush VA Medical Center, Indiana University School of Medicine, Indianapolis, IN, USA.
authors.forename: Tim
authors.initials: T
authors.lastname: Lahm
keywords: BAL, bronchoalveolar lavage; Bronchoalveolar lavage; COP, cryptogenic organizing pneumonia; CT, computer tomography; DLCO, diffusing capacity of the lung for carbon monoxide; EILI, etanercept induced lung injury; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; GGO, ground glass opacities; Hypersensitivity pneumonitis; Lymphocytic alveolitis; NSIP, non-specific interstitial pneumonia; RA, rheumatoid arthritis; Sarcoid-like reaction; TNF-α antagonist; TNF-α, tumor necrosis factor α; UIP, usual interstitial pneumonia; VATS, video assisted thoracic surgery