A study of peripheral airway findings using an ultrathin bronchofiberscope and bronchoalveolar lavage fluid with diffuse panbronchiolitis.

We investigated the peripheral airways using an ultrathin bronchofiberscope and analyzed bronchoalveolar lavage fluid (BALF) in 10 patients with diffuse panbronchiolitis (DPB; refractory and responsive to treatment with macrolide antibiotics) and 10 healthy volunteers. Refractory DPB patients had obstruction at the 11th or 12th level of bronchial branches and secretion from the 5th to 6th order bronchi to the 11th-12th level of bronchial branches. In responsive DPB patients, there was no obstruction of peripheral airways, but secretion in the bronchial lumens still remained in nearly all observed bronchial branches. Despite macrolide therapy, BALF from patients with refractory DPB contained a high percentage of neutrophils and had a lower CD4/CD8 ratio. Two-color analysis of T cell subsets in BALF revealed a high percentage and number of CD8+S6F1+ cells (activated cytotoxic T cells) in refractory DPB patients. Our findings suggest that obstruction around the terminal bronchioles may be correlated with BALF abnormalities and may be irreversible despite macrolide therapy in progressive DPB.