Abstract
After a 72-year-old male with glottic cancer received a permanent tracheostomy due to tracheostomal stenosis, dyspnea began to relapse and progress, and flexible fiberscopy disclosed the prominent finding of “a saber sheath type” of tracheobronchomalacia. Histopathological examinations at autopsy disclosed that the cartilage of the tracheobronchial tree was selectively destroyed in worm-eaten shapes or had completely disappeared, and was replaced by collagen fibers. Immunohistochemical examinations demonstrated that CD68-positive and HLA-DR-positive macrophages were present inside the cartilage cavities, and had accumulated at the destroyed portions of the cartilage. These pathological changes indicated that the cartilage of the tracheobronchial tree was selectively destroyed, and immunologically, macrophages with HLA class II antigen directly affected the chondrocytes. We propose a new concept of the immunohistopathogenesis of tracheobronchomalacia.
