May Be Caused by

 Common

Bronchogenic carcinoma

Chronic aspiration pneumonia

Hilar lymphadenopathy

Lymphoma

Metastasis

Pneumonia

Pulmonary edema

Tuberculosis

 Uncommon

Actinomycosis

Blastomycosis

Coal-worker pneumoconiosis

Fungal disease

Hemolytic-uremic syndrome

Lipoid pneumonia

Pneumoconiosis

Pulmonary hemorrhage

Silicosis

 Rare

Alveolar proteinosis