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Delayed diagnosis for primary tracheobronchial amyloidosis.

OBJECTIVE
To determine clinical features and diagnostic methods for primary tracheobronchial amyloidosis (TBA). 


METHODS
The clinical manifestations and diagnosis of a male patient who had been misdiagnosed for many years were described and analyzed. 


RESULTS
The patient was a 68-year-old male who complained of recurrent cough, expectoration, and progressive dyspnea for more than 30 years. He had been diagnosed with chronic bronchitis, bronchiectasis, and endobronchial tuberculosis in other hospitals and treated with antibiotics frequently and anti-tubercular agents for 3 months. Despite the treatments, the patient's symptoms were progressively worse. Finally, he came to Xiangya Hospital, Central South University, and was clearly diagnosed with primary TBA based on histopathological evidence after bronchoscopy. 


CONCLUSION
TBA, a rare disease resulting from abnormal submucosal amyloid deposition in the trachea and bronchi, may display with many different symptoms. TBA is often misdiagnosed with other pulmonary diseases. The use of bronchoscopic techniques is essential for the diagnosis of TBA. Histopathology remains the gold standard for diagnosis of primary TBA. So, for patients with chronic cough of unknown etiology, bronchoscopy should be performed to obtain biopsy samples for the definitive diagnosis.