September 2023
Dysphagia Secondary to Tracheobronchial Amyloidosis
Authors:
Dr Henry Sheppard, Radiology Registrar, University Hospital Southampton
Dr Katie Johnson, Consultant Radiologist, Salisbury District Hospital
Dr Rohan Mehta, Respiratory Consultant, Salisbury District Hospital
History:
A 72-year old lady underwent an unenhanced CT chest as follow up for pulmonary nodules following a PET/CT six months earlier. She had recently been reporting dysphagia of tablets and weight loss. A recent barium swallow has noted some extrinsic compression of the oesophagus.
Images:
Figure 1: Unenhanced CT chest in axial plane demonstrating irregular circumferential thickening of the trachea with calcification.
Figure 2: Unenhanced CT chest in axial plane demonstrating irregular circumferential thickening and calcification of the main bronchi.
Figure 3: Unenhanced CT chest in reconstructed coronal plane with soft tissue window demonstrating diffuse thickening and luminal narrowing of the trachea and bronchi.
Figure 4: Unenhanced CT chest in reconstructed sagittal plane demonstrates involvement of the posterior wall of the trachea.
Figure 5: Unenhanced CT chest in the axial plane demonstrating tracheal thickening causing extrinsic compression of the oeseophagus which likely explains the patient’s dysphagia.
Figure 6: PET/CT in axial plane demonstrating no abnormal uptake.
Diagnosis – Tracheobronchial amyloidosis causing extrinsic oesophageal compression.
Amyloidosis is a complex and heterogenous disease caused by the accumulation of proteins. It can be grouped into primary, secondary, hereditary, senile or localised amyloidosis. Tracheobronchial amyloidosis is a rare subtype of pulmonary amyloidosis which may occur in isolation, or as part of multisystem amyloidosis (Shi et al., 2013).
The clinical findings are non-specific and include dyspnoea, cough, haemoptysis and wheeze. There are some anecdotal reports of dysphagia (Yiotakis et al., 2009). The condition is often progressive and leads to airway narrowing. Treatments such as bronchoscopic debridement and laser therapy may be attempted, but often do not reverse the narrowing (OʼRegan et al., 2000). Radiation therapy or local excision have also been described (Monroe et al., 2004, Kurrus et al., 1998).
Plain radiography may demonstrate nodular and irregular narrowing of the airways and, in severe cases, cause lobar collapse secondary to endobronchial obstruction (Mangla et al., 2020).
CT studies may demonstrate circumferential segmental mucosal thickening with, or without calcifications and luminal narrowing (Shi et al., 2013). Importantly, the posterior wall is not spared (Milani et al., 2017). Rarely, tumour-like formations may develop (Naef et al., 1977).
The definitive diagnosis of tracheobronchial amyloid involves fiberoptic bronchoscopy and histological assessment (Shi et al., 2013).
The main differentials include tracheobronchopathia osteochondroplastica, a benign, idiopathic condition characterised by the development of benign sub-centimeter osseous or cartilaginous nodules. It primarily affects the lower trachea and proximal bronchi (Prince et al., 2002). CT findings are similar with nodular thickening of the tracheal cartilage but, crucially, sparing the posterior membrane (Webb et al., 2000).
Relapsing polychondritis is a multisystem, autoimmune, disease characterised by recurrent and progressive inflammation of cartilage. The average period of onset is middle age. It causes smooth thickening and luminal narrowing of the trachea and bronchi but, again, spares the posterior wall (Lee et al., 2006). Tracheal cartilage calcification, lobar air trapping and dynamic tracheal collapse may be demonstrated (Yap, 2023).
Whilst performing a literature search in preparation for this article, it is evident that there is a lack of high quality resources. Almost all of the available information is from case reports and anecdotal evidence.
Questions:
Which of the following are true about the diagnosis and treatment of tracheobronchial amyloid?
Bronchoscopic debridement prevents further airway narrowing (F)
The anterior and lateral walls become thickened, whilst the posterior wall is spared (F)
Plain radiography may demonstrate nodular thickening of the trachea (T)
Airway narrowing is a necessary feature on CT imaging (F)
The trachea may be the only tissue affected by amyloid (T)
Which of the following are true regarding tracheobronchopathia osteochondroplastica?
It is characterised by small osseous or cartilaginous nodules forming in the trachea (T)
The posterior membrane of the trachea of involved (F)
It is premalignant (F)
The upper trachea is typically spared (T)
The trachea is diffusely thickened (F)
Which of the following are true regarding relapsing polychondritis?
It often presents in childhood (F)
It is localised to the trachea and bronchial tree (F)
It causes smooth thickening of the trachea and bronchi (T)
Calcification of the tracheal cartilage may be demonstrated (T)
It is associated with dynamic tracheal collapse (T)
References:
Kurrus, J.A. et al. (1998) ‘Radiation therapy for tracheobronchial amyloidosis’, Chest, 114(5), pp. 1489–1492. doi:10.1378/chest.114.5.1489.
Lee, K.S. et al. (2006) ‘Relapsing polychondritis: Prevalence of expiratory CT airway abnormalities’, Radiology, 240(2), pp. 565–573. doi:10.1148/radiol.2401050562.
Mangla, L. et al. (2020) ‘Tracheobronchial Amyloidosis: An uncommon disease with a common presentation’, Respirology Case Reports, 8(7). doi:10.1002/rcr2.630.
Milani, P. et al. (2017) ‘The lung in amyloidosis’, European Respiratory Review, 26(145), p. 170046. doi:10.1183/16000617.0046-2017.
Monroe, A.T. et al. (2004) ‘Tracheobronchial Amyloidosis’, Chest, 125(2), pp. 784–789. doi:10.1378/chest.125.2.784.
Naef, A.P. et al. (1977) ‘Amyloid pseudotumor treated by tracheal resection’, The Annals of Thoracic Surgery, 23(6), pp. 578–581. doi:10.1016/s0003-4975(10)63707-1.
OʼRegan, A. et al. (2000) ‘Tracheobronchial Amyloidosis: The Boston University Experience from 1984 to 1999’, Medicine, 79(2), pp. 69–79. doi:10.1097/00005792-200003000-00001.
Prince, J.S. et al. (2002) ‘Nonneoplastic lesions of the tracheobronchial wall: Radiologic findings with Bronchoscopic Correlation’, RadioGraphics, 22(suppl_1). doi:10.1148/radiographics.22.suppl_1.g02oc02s215.
Shi, Z. et al. (2013) ‘Primary tracheobronchial amyloidosis: Coronal CT scan may provide clues for early diagnosis’, Journal of Postgraduate Medicine, 59(3), p. 223. doi:10.4103/0022-3859.118045.
Webb, E.M., Elicker, B.M. and Webb, W.R. (2000) ‘Using CT to diagnose nonneoplastic tracheal abnormalities’, American Journal of Roentgenology, 174(5), pp. 1315–1321. doi:10.2214/ajr.174.5.1741315.
Yap, J. (2023) Relapsing polychondritis: Radiology reference article, Radiopaedia Blog RSS. Available at: https://radiopaedia.org/articles/relapsing-polychondritis?lang=gb (Accessed: 03 July 2023).
Yiotakis, I. et al. (2009) ‘Primary localized laryngeal amyloidosis presenting with hoarseness and Dysphagia: A case report’, Journal of Medical Case Reports, 3(1), p. 9049. doi:10.4076/1752-1947-3-9049.