Pulmonary amyloidosis: radiographic finding of nodular opacities in a heavy smoker.

Pulmonary amyloidosis is a rare disease, characterized by extracellular deposition of fibrillary protein in the lungs. Amyloidosis is a generic term for a heterogeneous group of diseases, including Alzheimer's disease and type 2 diabetes mellitus. In the respiratory system, it appears in various forms: tracheobronchial; nodular pulmonary; and alveolar septal (diffuse parenchymal).