Ten consecutive patients with a diagnosis of IPF were recruited from Montefiore-North Central Bronx Hospital Center on initial presentation to enter this study. All subjects gave informed consent for the procedures, which were approved by the Institutional Review Board. The diagnosis of IPF was established by a combination of medical history, physical examination, laboratory tests, chest roentgenograms, pulmonary function tests (PFTs), arterial blood gas analyses, and the results of lung biopsies according to previously described criteria. Histologic confirmation of the diagnosis was obtained by transbronchial lung biopsy in four patients and by open lung biopsy in six patients. Here
All patients underwent BAL as described below at the time of bronchoscopy. None of the patients were current smokers at the time of presentation, and seven of ten were lifelong nonsmokers. After diagnosis, all patients were treated with prednisone, 1 mg/kg/day, until their pulmonary function stabilized for one month (average treatment time 2 ±0.5 months). At this time patients who agreed (eight of ten) underwent a second BAL procedure. At each bronchoscopy 30 ml of heparinized peripheral blood was obtained to determine peripheral blood lymphocyte activity for comparison with BAL lymphocytes. Eight normal subjects underwent bronchoscopy with BAL and donated 30 ml of peripheral blood for comparative purposes with the study subjects. These normal subjects gave informed consent, and were all nonsmokers who had normal results on PFTs, chest roentgenograms, and were PPD-negative.
Clinical Laboratory Tests
Pulmonary Function Tests: Full lung volumes, single-breath diffusing capacity for carbon monoxide, and spirometry before and after bronchodilator treatment were performed (Collins DS Plus Pulmonary Testing System). All patients underwent the above studies prior to the initial bronchoscopy. Serial PFT studies were performed two weeks after beginning therapy and monthly thereafter. Gallium scintiscans were also obtained on all ten IPF patients.