The spectrum of pulmonary amyloidosis

Amyloidosis is a disease caused by misfolded proteins that deposit in the extracellular matrix as fibrils, resulting in the dysfunction of the involved organ. The lung is a common target of Amyloidosis, but pulmonary amyloidosis is uncommonly diagnosed since it is rarely symptomatic. Diagnosis of pulmonary amyloidosis is usually made in the setting of systemic amyloidosis, however in cases of localized pulmonary disease, surgical or transbronchial tissue biopsy might be indicated. Pulmonary amyloidosis can be present in a variety of discrete entities. Diffuse Alveolar septal amyloidosis is the most common type and is usually associated with systemic AL amyloidosis. Depending on the degree of the interstitial involvement, it may affect alveolar gas exchange and cause respiratory symptoms. Localized pulmonary Amyloidosis can present as Nodular, Cystic or Tracheobronchial Amyloidosis which may cause symptoms of airway obstruction and large airway stenosis. Pleural effusions, mediastinal lymphadenopathy and pulmonary hypertension has also been reported. Treatment of all types of pulmonary amyloidosis depends on the type of precursor protein, organ involvement and distribution of the disease. Most of the cases are asymptomatic and require only close monitoring. Diffuse alveolar septal amyloidosis treatment follows the treatment of underlying systemic amyloidosis. Tracheobronchial amyloidosis is usually treated with bronchoscopic interventions including debulking and stenting or with external beam radiation. Long-term prognosis of pulmonary amyloidosis usually depends on the type of lung involvement and other organ function.

Atypical primary pulmonary amyloidosis: A rare case report

RATIONALE

Pulmonary amyloidosis is a rare respiratory disease characterized by amyloid deposition in the lungs. The clinical manifestations of pulmonary amyloidosis are variable and without specific symptoms.

PATIENT CONCERNS

We report a rare case of tracheobronchial amyloidosis to improve our understanding of the disease.

DIAGNOSES

The diagnosis of tracheobronchial amyloidosis was finally established by transbronchoscopic lung biopsy and histological examination.

INTERVENTIONS

The patient significantly improved with methylprednisolone sodium succinate for injection (40 mg/day) for 5 days and low-dose oral prednisone for 10 days.

OUTCOMES

After treatment, discomfort, such as cough, stridor, dyspnea, and chest tightness, disappeared, and he was discharged. The patient was in good clinical condition after 8 months of follow-up.

CONCLUSION

This case clearly shows that it is difficult to distinguish tracheobronchial amyloidosis from other diseases with manifestations of cough, dyspnea and chest tightness because of their similar symptoms and imaging findings. Thus, the role of transbronchoscopic lung biopsy and histological examination in the diagnosis of tracheobronchial amyloidosis is very important.

The lung in amyloidosis

Amyloidosis is a disorder caused by misfolding of autologous protein and its extracellular deposition as fibrils, resulting in vital organ dysfunction and eventually death. Pulmonary amyloidosis may be localised or part of systemic amyloidosis.

Pulmonary interstitial amyloidosis is symptomatic only if the amyloid deposits severely affect gas exchange alveolar structure, thus resulting in serious respiratory impairment. Localised parenchymal involvement may be present as nodular amyloidosis or as amyloid deposits associated with localised lymphomas. Finally, tracheobronchial amyloidosis, which is usually not associated with evident clonal proliferation, may result in airway stenosis.

Because the treatment options for amyloidosis are dependent on the fibril protein type, the workup of all new cases should include accurate determination of the amyloid protein. Most cases are asymptomatic and need only a careful follow-up. Diffuse alveolar-septal amyloidosis is treated according to the underlying systemic amyloidosis. Nodular pulmonary amyloidosis is usually localised, conservative excision is usually curative and the long-term prognosis is excellent. Tracheobronchial amyloidosis is usually treated with bronchoscopic interventions or external beam radiation therapy.

[Bronchopulmonary amyloidosis: report of four cases]

Amyloidosis limited to bronchopulmonary apparatus is expressed as tracheobronchial deposits in diffuse plaques that can cause stenosis or parenchymal nodules or masses. In this regard, we report four cases of pulmonary amyloidosis and discuss the diagnostic difficulties of this location. These are two women and two men aged 60, 68, 44 and 57 years. They presented a pulmonary parenchymal amyloidosis in all cases associated with bronchial in one case. The diagnosis was confirmed by histology in all cases. The staging was negative in all cases. The evolution was marked by the stabilization of the lesions in all cases. Localized amyloidosis, which may be the only telltale sign of a systemic illness, its diagnosis requires finding other locations to better tailor the treatment strategy.

Localized amyloidosis of the genitourinary tract: report of 5 new cases and review of the literature

Primary localized amyloidosis of the genitourinary tract is a rare entity characterized by small pseudotumors localized in the renal pelvis, ureters, or bladder. Amyloid fibrils are derived from immunoglobulin light chains, but no systemic plasma cell proliferation is detected. The clinical and radiologic features mimic urinary tract cancer, and local treatment is indicated. The prognosis is excellent in most cases, although disease recurrence is possible. We report 5 new cases of localized amyloidosis of the urinary tract, with lambda (4/5), or kappa (1/5) chain amyloid protein, involving the bladder (5/5), and the ureter and renal pelvis (1/5), with multiple, bilateral lesions in 1 case. The presenting complaint was painless hematuria in 4 cases. All cases were of primary (AL)-type amyloidosis. All patients underwent extensive investigation, and none presented any signs of generalized amyloidosis. A favorable outcome was observed in every case. We performed a comprehensive review of the literature, and summarize the data.

[Haemoptysis revealing tracheobronchial amyloidosis]

The authors report the case of a 68-year-old man complaining of haemoptysis and breathlessness. Bronchoscopy revealed a budding formation in tracheal bifurcation. Multiple biopsies were performed and concluded as to AL type amyloidosis. Tracheobronchial amyloidosis is an uncommon localised form of amyloidosis that can simulate lung cancer.

Unusual combination of tracheobronchopathia osteochondroplastica and AA amyloidosis

Tracheobronchopathia osteochondroplastica (TO) is a rare disorder of unknown cause characterized by the presence of multiple submucosal osseous and/or cartilaginous nodules that protrude into the lumen of the trachea and large bronchi. A simultaneous diagnosis of TO and amyloidosis is rarely reported. In this report, a case initially suspected to be asthma bronchiole that could not be treated, was radiologically diagnosed as TO, and also secondary amyloidosis is presented. A 53 years, man patient reported a 3 years history of dyspnea. Pulmonary function tests (PFTs) showed an obstructive pattern. Chest X-rays revealed right middle lobe atelectasis. FOB and CT detected nodular lesions in the trachea and in the anterior and lateral walls of the main bronchi. AA amyloidosis was confirmed by endobronchial biopsy. In the abdominal fat pad biopsy, amyloidosis was not detected. Asthma bronchiole was excluded by PFTs. This case illustrates that it is possible for TO and amyloidosis to masquerade as asthma. TO and amyloidosis should be suspected in patients of older ages with asthma and especially with poorly treated asthmatic patients. Although nodular lesions in the anterior and lateral tracheobronchial walls are typical for TO, a biopsy should be obtained to exclude amyloidosis.

Plasma cell dyscrasias and amyloidosis

The plasma cell dyscrasias and amyloidosis are distinct clinical entities that may co-exist. Both disease processes may present with manifestations in the head and neck, making familiarity with these conditions by otolaryngologists essential. Prompt diagnosis and evaluation for systemic disease are crucial in proper treatment planning.