Tracheobronchial amyloidosis managed with multimodality therapies

Tracheobronchial mucosal keratosis: A literature review of this rare disorder

Background

Tracheobronchial mucosal keratosis (TBMK) is a rare airway disease that may cause refractory cough and airway stenosis. The characteristics of this disease remain unknown. In the present study, we describe this disorder based on a review of the current literature, emphasizing its diagnostic and therapeutic aspects.

Methods

A comprehensive search of TBMK was performed in Medline, Google Scholar, Web of Science, Cochrane Library (UK), Embase, China National Knowledge Infrastructure (CNKI) (China), and Wan Fang Med Online (China). The following data were collected: patient characteristics, chest imaging findings, bronchoscopy, histopathologic findings, pathogen testing, treatment, and prognosis.

Results

As of 2023, eighteen cases of TBMK have been reported. The main clinical manifestations were cough and expectoration. Chest imaging findings were non-specific. The main bronchoscopy findings were nodular protrusion of airway lumen and yellow-white purulent moss above the nodular lesion. The lesions were mainly located in the trachea and mainstem bronchus. The main pathological manifestations include keratinocytes or keratinocyte beads, squamous metaplasia, and mucosal inflammatory changes. The treatments that were administered include antibiotics, symptomatic treatment, and glucocorticoids. All methods were ineffective except for bronchoscopy-guided high-frequency electric knife and recombinant human epidermal growth factor treatment.

Conclusions

TBMK is a rare respiratory disease with atypical clinical manifestations and chest computed tomography findings. Bronchoscopy revealed that nodular hyperplasia of the airway and purulent fur-covered lesions are typical manifestations. The final diagnosis needs to be confirmed by histopathological examination. There is a lack of effective treatment for this disease, and bronchoscopy-guided intervention therapy may be a candidate treatment.

Management of tracheobronchial amyloidosis: a review of the literature

Introduction

Tracheobronchial amyloidosis is a rare idiopathic disorder characterised by extracellular deposition of misfolded protein fibrils in the tracheobronchial tree. It presents with nonspecific symptoms. Deciding on the best treatment approach can be challenging due to the lack of a treatment guideline. We undertook a review to assess the therapeutic options for tracheobronchial amyloidosis and to highlight gaps within the existing evidence.

Methods

We performed a literature search from 1 January 1990 until 1 March 2022 to identify relevant literature regarding patient characteristics, symptoms, management and prognosis for patients with tracheobronchial amyloidosis.

Results

77 studies consisting of 300 patients were included. We found a great heterogeneity in the management of tracheobronchial amyloidosis patients. Although a fifth of the reported patients were managed with a wait-and-see approach, many different treatments were used as a single intervention, or multiple treatments were combined. An interesting finding is the slightly higher percentage of patients with Sjögren syndrome (n=5, 1.7%) and tracheobronchial amyloidosis compared to the normal population (0.5-1.0%).

Conclusions

There is a great heterogeneity in the management of tracheobronchial amyloidosis patients. The treatment is still based on expert opinion due to the lack of a treatment guideline. Various treatment approaches include a wait-and-see approach, external beam radiotherapy, therapeutic bronchoscopy, immunosuppressive treatment and surgery.

Primary Tracheobronchial Amyloidosis Presenting with an Upper Airway Obstruction

This is a case of localized primary tracheobronchial amyloidosis in a patient who presented with upper airway obstruction. Tracheobronchial amyloidosis is a type of localized bronchopulmonary amyloidosis that is frequently overlooked. It involves the deposition of amyloid protein on the tracheal and bronchial tissue, leading to progressive tracheal stenosis and airway obstruction that can be seen on imaging as a tracheal mass. Because of its significant diagnostic difficulty and therapeutic conundrum, it ought to be considered in the differential diagnosis of upper airway symptoms with an unknown etiology.

Localized tracheobronchial amyloidosis: A rare case presentation and tailored management approaches

Localized tracheobronchial amyloidosis (TBA) is a rare manifestation of pulmonary amyloid disease, and can result in central airway obstruction. The nature of presentation is variable and there may be a delayed diagnosis. TBA has a variable prognosis and the most commonly used strategy for management is airway recanalization. Here, we describe the tailored management approach for a 64-year-old Caucasian female presenting with localized TBA of the left main bronchus. Pulmonary function testing, computed tomography and positron emission tomography results are detailed. Rigid bronchoscopy was utilized for diagnostic and therapeutic intervention, which involved debulking and stent insertion. Amyloid deposition and localized inflammation were identified through histopathology. Focal external beam radiation therapy was administered following multidisciplinary discussion and review of the literature, with no evidence of active disease at 6 months follow-up.

The Lung in Dysregulated States of Humoral Immunity

In common variable immunodeficiency, lung manifestations are related to different mechanisms: recurrent pneumonias due to encapsulated bacteria responsible for diffuse bronchiectasis, diffuse infiltrative pneumonia with various patterns, and lymphomas, mostly B cell extranodal non-Hodgkin type. The diagnosis relies on significant serum Ig deficiency and the exclusion of any primary or secondary cause. Histopathology may be needed. Immunoglobulin (IgG) replacement is crucial to prevent infections and bronchiectasis. IgG4-related respiratory disease, often associated with extrapulmonary localizations, presents with solitary nodules or masses, diffuse interstitial lung diseases, bronchiolitis, lymphadenopathy, and pleural or pericardial involvement. Diagnosis relies on international criteria including serum IgG4 dosage and significantly increased IgG4/IgG plasma cells ratio in pathologically suggestive biopsy. Respiratory amyloidosis presents with tracheobronchial, nodular, and cystic or diffuse interstitial lung infiltration. Usually of AL (amyloid light chain) subtype, it may be localized or systemic, primary or secondary to a lymphoproliferative process. Very rare other diseases due to nonamyloid IgG deposits are described. Among the various lung manifestations of dysregulated states of humoral immunity, this article covers only those associated with the common variable immunodeficiency, IgG4-related disease, amyloidosis, and pulmonary light-chain deposition disease. Autoimmune connective-vascular tissue diseases or lymphoproliferative disorders are addressed in other chapters of this issue.

Primary localized tracheobronchial amyloidosis presenting with massive hemoptysis: a case report and literature review

Primary localized tracheobronchial amyloidosis (TBA) is a rare respiratory tract dysfunction, which is a heterogeneous group of diseases involving abnormal extracellular deposition of amyloid and autologous fibrillar protein material in β-pleated sheets. A 64-year-old man was referred to our hospital because of hemoptysis. Physical examination showed decreased breath sounds in the right lung on auscultation. Chest computed tomography scan displayed multiple nodules with varied size in main bronchia around bilateral hilus of the lung. After admission, bronchoscopy was performed for this patient, and roughness of mucosa in trachea and multiple nodules in respiratory tract were observed. Through further tissue biopsy, the diagnosis of primary TBA was confirmed.

Pathophysiology and treatment of cardiac amyloidosis

Amyloid cardiomyopathy should be suspected in any patient who presents with heart failure and preserved ejection fraction. In patients with echocardiographic evidence of ventricular thickening and without a clear history of hypertension, infiltrative cardiomyopathy should be considered. If imaging suggests the presence of amyloid deposits, confirmation by biopsy is required, although endomyocardial biopsy is generally not necessary. Assessment of aspirated subcutaneous fat and bone-marrow biopsy samples verifies the diagnosis in 40-80% of patients, dependent on the type of amyloidosis. Mass spectroscopy can be used to determine the protein subunit and classify the disease as immunoglobulin light-chain amyloidosis or transthyretin-related amyloidosis associated with mutant or wild-type TTR (formerly known as familial amyloid cardiomyopathy and senile cardiac amyloidosis, respectively). In this Review, we discuss the characteristics of cardiac amyloidosis, and present a structured approach to both the assessment of patients and treatment with emerging therapies and organ transplantation.