Nodular pulmonary amyloidosis: a complex disease with malignancy association

Abstract

Pulmonary amyloidosis is a rare disease that incorporates deposition of amyloid microfibril material in the lung parenchyma. The condition generally presents as an indolent subacute-to-chronic pulmonary disease and requires tissue biopsy to establish the diagnosis. Nodular pulmonary amyloidosis, a subtype of pulmonary amyloidosis, is characterised by special radiographic and pathological features. While the disease can be associated with inflammatory conditions; its association with mucosal-associated lymphoid tissue (MALT lymphoma) is unusual and carries management challenges. Herein, we illustrate a case study of nodular pulmonary amyloidosis associated with underlying MALT lymphoma in a patient with known systemic lupus erythematosus. The aim of this article is to share the management experience of this complex condition with the medical community and to conduct an up-to-date literature review on nodular pulmonary amyloidosis.

Keywords: adult intensive care; haematology (incl Blood Transfusion); interstitial lung disease; respiratory medicine.

Figure 1

(A) Chest X-ray showing nodular opacities and infiltrates in both middle and lower lung fields. (B) Chest CT showing bilateral, prominent, ill-defined nodular opacities occupying both lungs in the middle-to-lower fields causing narrowing of the pulmonary arteries (arrows). Although those findings are non-specific, they may suggest inflammatory or neoplastic pulmonary process.

Figure 2

(A) Pathology image of the right lower lobe wedge resection revealed multiple foci of nodular amyloidosis within the alveolar space (arrows), associated with stromal fibrosis, patchy perivascular and septal amyloid deposition, H&E×4. Amyloid phenotyping by mass spectrometry analysis confirmed the diagnosis of amyloidosis. (B) Congo-red stain showing apple-green birefringence confirming the diagnosis of pulmonary amyloidosis. (C) Negative CD20 staining of the sample, indicating amyloidosis with no evidence of lymphoma or lymphoproliferative disease.

Figure 3

(A) Chest X-ray showing worsening opacities of both lung fields, which is more prominent on the left side with almost complete lung involvement as compared with chest X-ray after treatment with rituximab and high dose glucocorticoids as shown in panel B. (C) CT showing worsening interstitial opacities in both lung fields with nodular infiltrates with bilateral moderate pleural effusions (arrows). Image is compared with CT after treatment as shown in panel D.

Figure 4

Fibreoptic bronchoscopy image of the left main bronchus showing the bifurcation of the left upper and middle segmental bronchi. Mucosa appeared to be friable and oedematous (arrows).

Figure 5

(A) Pathology image of the bronchial biopsy obtained from main stem of left lung revealed dense lymphocytic proliferation underneath the benign bronchial mucosa, H&E ×10 original magnification. (B) Immunostaining of CD20 showed predominant small to medium B lymphocytes that confirms the diagnosis of extranodal marginal zone B cell lymphoma, MALT type, ×10 original magnification.