Pneumococcal aortitis with rupture of the aorta. Report of a case and review of the literature.

Microbial arteritis, an entity often considered under the category of mycotic aneurysms, is an uncommon infectious process which generally results from bacteremic seeding of a preexisting aortic lesion. This report describes a fatal case of microbial arteritis involving a 51-year-old man who presented as an outpatient with diffuse myalgias and abdominal pain of approximately two weeks' duration. Necropsy finding revealed an exsanguinating hemorrhage from an infected nonaneurysmal abdominal aortic plaque caused by Streptococcus pneumoniae. Documented cases of microbial aortitis due to S. pneumoniae are quite rare in present times and were not often observed in the preantibiotic era even in the setting of bacterial endocarditis. The pathology, pathogenesis, and incidence of aneurysmal and nonaneurysmal aortic infections, with special reference to the pneumococcus, are reviewed.