Localized amyloidosis of the lower respiratory tract.

Amyloidosis limited to the lower respiratory tract is a relatively rare condition. Three new patients are reported, and the pertinent literature is reviewed. The available information is discussed with regard to clinical forms, diagnostic methods, therapy, and clinical course. Tracheobronchial deposition is the most frequent form of localized amyloidosis; it affects relatively younger persons and often gives rise to symptoms of airway obstruction. Bronchoscopy, although carrying a risk of bleeding, is the procedure of choice diagnostically and therapeutically. Single or multiple pulmonary nodules are usually discovered as an incidental roentgenographic finding, and surgical resection (for suspected malignancy) has resulted in cure in all cases. On rare occasions, amyloid may be deposited diffusely in the pulmonary parenchyma, leading to death from respiratory insufficiency.