Bilateral proximal pulmonary artery aneurysms simulating hilar adenopathy.

Proximal pulmonary artery aneurysms (PAAs) are rare. Most are associated with secondary pulmonary hypertension or a variety of rare systemic disorders. An asymptomatic adult patient presented with bilateral hilar enlargement on a routine chest roentgenogram. Computed tomography of the chest revealed 5 cm bilateral proximal PAAs with a normal pulmonary trunk. The clinician should consider proximal PAA in the differential diagnosis of hilar enlargement.