Localized Tracheobronchial Transthyretin Amyloidosis Diagnosed After Hemoptysis: A Case Report.

Pulmonary involvement in transthyretin amyloidosis (ATTR) is rare, and tracheobronchial involvement is particularly uncommon. We report a case of wild-type ATTR amyloidosis presenting with hemoptysis in a 66-year-old woman with dyspnea. Chest computed tomography revealed bronchial wall thickening and infiltrative opacities. Bronchoscopy showed irregular mucosal lesions extending from the trachea to both bronchi. Histopathological examination of bronchial biopsy specimens showed Congo red-positive deposits, and immunohistochemistry confirmed transthyretin, establishing the diagnosis of ATTR amyloidosis. Systemic evaluation and genetic testing excluded systemic and hereditary disease, leading to a diagnosis of localized wild-type ATTR. Bronchial aspirate cultures yielded Aspergillus fumigatus and Mycobacterium mucogenicum, and antifungal therapy was administered for a suspected concomitant airway infection. This rare presentation of tracheobronchial-localized ATTR amyloidosis underscores the importance of considering amyloidosis in the differential diagnosis of hemoptysis and the diagnostic role of bronchoscopy.