Abstract
A patient in whom asthma preceded the development of multiple pulmonary and systemic artery aneurisms died after dissection of the aorta. At necropsy he was found to have widespread arteritis of unknown aetiology affecting many large and medium-sized pulmonary and systemic vessels as well as a few microscopic ones. Endarteritis obliterans was present in some of the vasa vasorum. The clinical and histopathological findings are discussed in relationship to other known causes of arteritis, and it is concluded that this condition has not previously been described.