Lung diseases arising from lymphoid-related origins can include a variety of conditions characterized by lymphoid tissue proliferation or infiltration. Some notable examples are:
- Pulmonary Lymphoid Hyperplasia: This includes conditions like follicular bronchiolitis, where there is hyperplastic lymphoid tissue in the bronchioles, leading to respiratory symptoms.
- Follicular bronchiolitis is characterized by lymphoid proliferation in the lungs, and this relationship
- Lymphocytic Interstitial Pneumonia (LIP): A rare lung disease characterized by lymphoid infiltration of the lung interstitium, often associated with autoimmune disorders, infections, or immunodeficiencies.
- IgG4-Related Lung Disease: A systemic condition that can lead to interstitial pneumonia and lymphoid hyperplasia, often involving bronchial and lymphatic structures.
- NSIP is characterized by a uniform interstitial infiltrate that primarily consists of lymphocytes and plasma cells.There can be a prominent lymphoid component, which may lead to areas of lymphoid hyperplasia or organized lymphoid follicles within the lung tissue.Causes of Lymphoid Proliferation: Lymphoid proliferation in NSIP can be associated with underlying conditions, such as:Autoimmune diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus, Sjögren’s syndrome)The imaging features may overlap with those seen in conditions characterized by lymphoid hyperplasia, making differentiation based on imaging alone challenging.
- Non-Hodgkin Lymphoma (NHL): Primary pulmonary lymphoma can occur, where lymphoma arises directly in the lung tissue, often manifesting as pulmonary nodules or masses.
- Hodgkin Lymphoma: While primarily a lymphatic system malignancy, it can involve the lungs, typically presenting with lymphadenopathy and pulmonary infiltrates.
- Sarcoidosis: Though primarily a granulomatous disease, it involves lymphoid tissue and may present with enlarged hilar lymph nodes and interstitial lung disease.
- Bronchiolitis Obliterans Organizing Pneumonia (BOOP): Also known as cryptogenic organizing pneumonia (COP), this condition involves the presence of granulation tissue in the airspaces and is often associated with lymphoid tissue infiltration.
- Post-Transplant Lymphoproliferative Disorder (PTLD): This occurs in immunocompromised individuals, such as organ transplant recipients, and may involve the lungs.
These conditions highlight the diverse ways in which lymphoid tissue can impact lung health, either through direct involvement or as part of systemic diseases.