[Diagnosis of primary tracheobronchial amyloidosis by multiplanar reconstruction of the computed tomography combined with bronchoscope].

OBJECTIVE

To summarize the specific CT characteristics and the endoscopic findings of primary tracheobronchial amyloidosis (PTBA) for improvement of the diagnostic accuracy.

METHODS

The imaging features of 6 patients with PTBA were analyzed by multiplanar reconstructed CT and the fiberoptic bronchoscope, and the pathology were summarized retrospectively.

RESULTS

All PTBA patients received bronchoscopic examination and the definite diagnosis were confirmed by positive staining with Congo red. PTBA presented diffuse thickening of major airway and lumen stenosis in various degrees with scattered hemorrhage of the mucous membrane under CT and bronchoscope, which was more obvious in low part of trachea, main bronchus and lobar bronchus. The mucosa of trachea and bilateral main bronchi were irregular and bumpy with jutting nodes in 5 patients, which was called "wavy path" pattern. Widely nodular or stripy calcifications of airway were found in 4 patients, which was considered as specific imaging features in PTBA and was involved bilateral main bronchi largely. There were obstructive atelectasis in 2 patients, and calcifications of hilus of lung with longitudinal diaphragm lymph nodes in 3 patients, but they were not specific. Ignoring the extensive circumferential thickening of large airway, "wavy path sign" and rail-like calcification was mainly responsible for misdiagnosis of PTBA as endobronchial tuberculosis or other diseases.

CONCLUSION

Attentions to the specific imaging features on multiplanar CT and the endoscopic findings are the fundamentals to avoid the misdiagnosis of PTBA.