Tracheobronchial amyloidosis: an uncommon disease with a common presentation

Abstract

Amyloidosis is an uncommon heterogeneous and multi‐systemic disease characterized by extracellular amyloid deposition. The size of proteins varies and forms a part of local disease or systemic process. Light chain amyloidosis (AL) is the most prevalent form of systemic amyloidosis which may also be seen in localized disease. Isolated tracheobronchial amyloidosis (TBA) is rather unusual with local amyloid deposition which may pose a diagnostic dilemma with subsequent therapeutic challenge. Awareness of such a presentation is crucial in the diagnosis of this rare disease. We describe three cases who presented with haemoptysis, which on further evaluation were diagnosed as isolated TBA, and a review of literature.

Tracheobronchial amyloidosis: A case report and review of literature

“…As a result of this mucosal thickening, CT imaging in tracheobronchial amyloidosis typically shows narrowing of the airway, producing more than one-third tracheal or bronchial stenosis [2 , 4 , 8] , as seen in our patient. Occasionally, the disease may manifest as a raised, tumor-like mass of amyloid material (as in our case), and mimic malignancy [2 , 12 , 14] . The key to differentiate this from other etiologies is the predominant involvement of the posterior wall.…”

“…However, since a few rare cases of systemic spread have been reported in the literature [7] , screening for symptoms of systemic amyloidosis should be performed on any patient with confirmed tracheobronchial amyloidosis. While there is no known "cure" for tracheobronchial amyloidosis, treatment can be effective in reducing symptoms at least temporarily, especially with primary distal airway involvement, though the amyloids may return over time, requiring recurrent interventions over the years [14] , as reflected in our patient's history. Unfortunately, more serious cases, particularly those with proximal airway involvement, may be fatal [8] .…”

“…Tracheobronchial amyloidosis, manifested by amyloid deposits limited specifically to tracheal and bronchial tissue, is a rare disorder with only a few hundred published cases [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] . Patients classically present with non-specific symptoms related to fixed upper airway obstruction caused by tracheal stenosis [9] .…”

“…Patients classically present with non-specific symptoms related to fixed upper airway obstruction caused by tracheal stenosis [9] . Clinical symptoms include hoarseness, dyspnea, cough, stridor, hemoptysis, and dysphagia, which are similar to those caused by more common airway disorders, often leading to incorrect, missed, and delayed diagnosis [2 , 4 , 14] . While definitive diagnosis of tracheobronchial amyloidosis typically depends on bronchoscopy biopsy with congo red stain [13] , [14] , [15] , narrowing of the major airways often limits inspection of the tracheobronchial tree using bronchoscopy [8] .…”

“…Therefore, it is important to determine the fundamental CT imaging features of tracheobronchial amyloidosis. CT imaging has been found to reveal mucosal thickening, with or without calcification, of the trachea, main bronchus, lobar and segmental bronchi, together or in part with luminal narrowing [2 , 4 , 8 , 14] . As a result of this mucosal thickening, CT imaging in tracheobronchial amyloidosis typically shows narrowing of the airway, producing more than one-third tracheal or bronchial stenosis [2 , 4 , 8] , as seen in our patient.…”