<aside>
Hilar lymphadenopathy refers to the enlargement of lymph nodes at the lung hila, where the bronchi, pulmonary vessels, and lymphatics converge. It may be unilateral or bilateral and is a common finding in chest imaging, often requiring correlation with clinical history.
</aside>
| Infectious | • Tuberculosis (primary TB with Ghon focus + hilar nodes). • Fungal infections (histoplasmosis, coccidioidomycosis). • Viral infections (infectious mononucleosis, CMV). • Bacterial: atypical pneumonia, pertussis. | | --- | --- | | Granulomatous / Inflammatory | • Sarcoidosis – classically bilateral symmetric hilar lymphadenopathy (BHL) ± paratracheal nodes. • Hypersensitivity pneumonitis. • Pneumoconiosis (silicosis, berylliosis). | | Malignancy | • Lymphoma (Hodgkin, Non-Hodgkin). • Metastatic disease (lung cancer, breast cancer, testicular tumors). • Primary lung carcinoma – hilar node spread common. | | Other causes | • Drug reactions (e.g., phenytoin). • Connective tissue diseases (RA, SLE). |
| Modality | Imaging features |
|---|---|
| CXR | • Hilar fullness, lobulated/rounded opacities. |
| • Bilateral symmetric → sarcoidosis. | |
| • Unilateral/asymmetric → TB, lymphoma, metastasis. | |
| CECT | • Defines node size, morphology, distribution. |
| • Sarcoidosis: symmetrical hilar and right paratracheal nodes (“1-2-3 sign”). | |
| • Lymphoma: large, homogeneous, often conglomerated nodes. | |
| • TB/fungal: necrotic nodes with central low attenuation ± rim enhancement. | |
| • Metastasis: often irregular or necrotic nodes. | |
| PET-CT | Useful in oncological staging (lymphoma, lung cancer). |
27-year-old woman with chronic sarcoidosis. Coronal CT image displays extensive mediastinal lymphadenopathy. Lymph nodes show punctuates calcifications.
Mueller-Mang, C., Ringl, H., Herold, C. (2017). Interstitial Lung Diseases. In: Nikolaou, K., Bamberg, F., Laghi, A., Rubin, G.D. (eds) Multislice CT. Medical Radiology(). Springer, Cham. https://doi.org/10.1007/174_2017_151