A study of peripheral airway findings using an ultrathin bronchofiberscopeand 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 diffu se panbronchiolitis (DPB; refractory and responsive to treatment with macro lide antibiotics) and 10 healthy volunteers. Refractory DPB patients had ob struction at the 11th or 12th level of bronchial branches and secretion fro m the 5th to 6th order bronchi to the 11th-12th level of bronchial branches . In responsive DPB patients, there was no obstruction of peripheral airway s, but secretion in the bronchial lumens still remained in nearly all obser ved bronchial branches. Despite macrolide therapy, BALF from patients with refractory DPB contained a high percentage of neutrophils and had a lower C D4/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 r efractory DPB patients. Our findings suggest that obstruction around the te rminal bronchioles may be correlated with BALF abnormalities and may be irr eversible despite macrolide therapy in progressive DPB.