[Tracheopathia osteoplastica. A 100-year-old mystery].

Tracheopathia osteoplastica is a very rare disease of the tracheobronchial tree with unknown origin and etiopathogenesis. The characteristic features are intramucosal nodules in the tracheal and/or bronchial mucosa. The clinical symptoms are unspecific and in most of the cases are consequences of airway stenosis. A collective of patient cases (4 tracheobronchial biopsies and 16 autopsy cases) was established to study the histology of tracheopathia osteoplastica and consisted of surgical pathology specimens (biopsies) and autopsy material. The study revealed two different types of tracheal ossification and nodule formation: (1) degenerative changes with nodule formation and ossification (tracheopathia osteoplastica tuberosa) and (2) diffuse degeneration of the tracheal cartilage with ossification of the outer third of the cartilaginous rings (tracheopathia osteoplastica peripherica). The histological changes indicate that tracheopathia osteoplastica is a type of sclerosing tracheopathy but the degenerative focus is at an unusual place (in the middle of the cartilage). No type of new cartilage formation was found in any of the cases.