Pulmonary amyloidosis: A case with hilar and mediastinal involvement and a review of the literature

The clinical and radiographic features of an unusual case of symptomatic tracheobronchial amyloidosis is presented, and the literature regarding amyloidosis involving the respiratory system is reviewed. In our patient, amyloidosis of the left upper lobe bronchus was associated with enlargement of the hilar and mediastinal lymph nodes. There was no evidence of amyloidosis elsewhere in the body. Amyloidosis confined to the respiratory system is much less common than systemic amyloidosis. Respiratory amyloidosis can be broadly classified into three groups: pulmonary, pleural, and mediastinal amyloidosis. Pulmonary amyloidosis can be further classified into parenchymal and tracheobronchial amyloidosis. Clinical presentation is quite variable. Nodular pulmonary amyloidosis may be discovered as an incidental finding on a chest radiograph. Alveolar-septal amyloidosis presents as respiratory failure. Submucosal plaques may result in stricture formation causing bronchial narrowing and atelectasis. Management of respiratory amyloidosis varies with the type of presentation. If the patient is asymptomatic, no action is required. The tracheobronchial amyloid, if causing atelectasis or stricture formation, can be treated with laser therapy. If laser therapy fails, surgery can be performed. Respiratory amyloidosis secondary to primary systemic amyloidosis may respond to melphalan and prednisolone therapy.