Differential Diagnosis for Extensive Mediastinal Lymphadenopathy and Pulmonary Findings
Single Most Likely Diagnosis
- Sarcoidosis: This condition is characterized by the formation of granulomas in various parts of the body, including the lungs and lymph nodes. The presence of bilateral hilar lymphadenopathy, extensive mediastinal lymphadenopathy, and patchy ground-glass opacities with a peribronchovascular distribution are highly suggestive of sarcoidosis. The conglomeration of lymphadenopathy and the increase in size over time also support this diagnosis.
Other Likely Diagnoses
- Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma can present with extensive lymphadenopathy, including mediastinal and hilar involvement. The increase in size of the lymphadenopathy over time and the presence of centrilobular nodules could be indicative of lymphoma.
- Tuberculosis: Although less common in some regions, tuberculosis (TB) can cause significant lymphadenopathy, particularly in the mediastinum and hilar regions. The patchy ground-glass opacities and centrilobular nodules could also be seen in TB, especially in its early or disseminated forms.
- Histoplasmosis: This fungal infection can cause lymphadenopathy and pulmonary findings similar to those described, particularly in endemic areas. The presence of calcified lymph nodes on imaging might help differentiate histoplasmosis from other diagnoses.
Do Not Miss Diagnoses
- Lung Cancer with Lymph Node Metastases: Although less likely given the distribution and nature of the lymphadenopathy, lung cancer with metastasis to mediastinal and hilar lymph nodes is a critical diagnosis not to miss due to its significant implications for treatment and prognosis.
- Wegener's Granulomatosis (Granulomatosis with Polyangiitis): This autoimmune disorder can cause a wide range of pulmonary and systemic symptoms, including lymphadenopathy and ground-glass opacities. It's a diagnosis that requires consideration due to its potential for severe morbidity if not promptly treated.
Rare Diagnoses
- Langerhans Cell Histiocytosis (LCH): LCH can present with pulmonary nodules and cysts, as well as lymphadenopathy, although it is less common. It typically affects the lungs and can cause significant morbidity.
- Castleman Disease: This rare disorder can cause lymphadenopathy, including in the mediastinum, and can be associated with systemic symptoms. It's an important consideration in cases where more common diagnoses have been ruled out.
- Silicosis or Other Occupational Lung Diseases: In individuals with a history of exposure to silica or other harmful substances, silicosis or other occupational lung diseases could present with lymphadenopathy and pulmonary findings, although they are less likely given the specific pattern described.