Rupture of a solitary, erosive peripheral pulmonary artery aneurysm

Aneurysms of the pulmonary arteries and their branches are rare. Although they may occur as isolated congenital anomalies, they more frequently are associated with congenital heart disease and pulmonary arterial hypertension. Less common predisposing factors include primary pulmonary hypertension, collagen vascular disease, trauma, and pulmonary banding. Inflammatory or infectious contributing factors include chronic granulomatous infection, infective endocarditis, pneumonia, and the Hughes- Stovin and Behcet's syndromes. Chronic pulmonary arterial hypertension, due to an underlying left-to-right shunt, as well as a superimposed focal bacterial pneumonia were the etiologic factors in the develop ment of the segmental pulmonary artery aneurysm in our patient. The rarity of this constellation of predisposing factors and the diagnostic dilemma posed by the findings in our patient led us to report our case and review the pertinent literature.