ABSTRACT
Primary pulmonary amyloidosis is a rare condition that can be classified into the tracheobronchial, diffuse alveolar septal, and nodular parenchymal type. Tracheobronchial amyloidosis is characterized by deposition of fib rilar proteins in the tracheobronchial tree, and it can be subdivided into diffuse and focal varieties. In this report, a case of diffuse tracheobronchial amyloidosis confirmed by flexible fiberoptic bronchoscopic biopsy is presented. The patient was a 43-year old male with a chief complaint of cough and sputum for 20 days and dyspnea for one day. The chest CT scan showed diffusely thickened walls of both the main and lobar bronchi with calcification. The bronchoscopic findings showed nodular lesions of the trachea, a diffuse bronchial stenosis of both the main bronchi and a pinpoint narrowing of the left upper and right middle lobar bronchus. The biopsy showed submucosal deposits of homogenous eosinophilic amyloid materials and an apple-green birefringence under polarizing microscopy following the Congo-red stain.