A Unique Case of Combined Nodular and Tracheobronchial Amyloidosis

Abstract

Amyloidosis is a heterogeneous group of diseases characterized by the extracellular deposition of misfolded proteins that can affect either systemically or locally confined to one system. Pulmonary amyloidosis is rare and can be classified into three forms according to the anatomic site of involvement: nodular pulmonary amyloidosis, tracheobronchial amyloidosis and diffuse alveolar-septal amyloidosis. The former two usually represent localized amyloid disease and the latter represents systemic disease. Typically lung parenchymal and tracheobronchial amyloidosis do not present together in localized forms of pulmonary amyloidosis. Here we report a unique case of localized pulmonary immunoglobulin light-chain amyloidosis, manifested as both parenchymal nodules and tracheobronchial amyloid deposition.

Keywords: localized amyloidosis; pulmonary amyloidosis; pulmonary nodular amyloidosis; tracheobronchial amyloidosis.

Figure 1

(a) Chest CT shows multiple bilateral lung nodules, some with central calcifications (arrowhead) and variable-sized cysts (white arrows) in all lung lobes. Note, airway involvement with circumferential mural thickening of the right lower lobe (RLL) bronchi (black arrows) and narrowing of right middle lobe (RML) bronchi (black arrows). (b) Chest CT angiography shows diffuse ground-glass opacities most suggestive of hemorrhage (in the setting of hemoptysis) with persistence of multiple bilateral lung nodules and cysts. Note, presence of endobronchial soft-tissues within RML segmental and subsegmental bronchi (black arrows).

Figure 2

Flexible fiberoptic bronchoscopy shows multiple yellowish plaques (short arrows) and raised nodular infiltration (long arrows) of airway mucosa in (a) right upper lobe (b) right middle lobe.

Figure 3

Photomicrographs of the endobronchial biopsy (a) deposits of amorphous, eosinophilic, waxy-like material (A) with ossification (B), underlying the bronchial epithelium (arrow), H&E, 10x. (b) When stained with Congo red, the material is bright orange on light microscopy, H&E, 4x and (c) apple green birefringence under polarizing microscopy, Congo red, 10x.