- Infectious
— Fungal – Histoplasmosis, Blastomycosis, Candidiasis, Coccidiomycosis
— Bacterial – Tuberculosis, Mycoplasma, Tularemia - Immunologic – Sarcoidosis, Systemic lupus erythematosus
- Oncologic – Leukemia, Lymphoma (Hodgkins, Non-Hodkin), Metastasis
- Miscellaneous – Castleman disease
Approach to the differential diagnosis of hilar lymphadenopathy:
- The most common causes are histoplasmosis, tuberculosis, and leukemia / lymphoma
- Chest CT can more clearly demonstrate the amount of disease involvement and is better at demonstrating calcification of lung nodules and lymph nodes, the presence of which effectively rules out a diagnosis of malignancy and makes a diagnosis of histoplasmosis much more likely
- Send a urine culture to look for histoplasmosis
- Place a PPD to look for tuberculosis
- If the urine and PPD are negative, consider lymph node biopsy to rule out malignancy
Pediatric Imaging 