Mycotic aneurysm due to Yersinia enterocolitica.

Infections of the cardiovascular system, besides involving both natural and prosthetic heart valves, vascular grafts, and indwelling venous and arterial cannulas, may cause mycotic aneurysms. The latter frequently complicate endocarditis; however, they may occur as isolated phenomena. Enterobacteriaceae are uncommon etiologic agents in vascular infections; however, a patient is reported who presented initially with a bacteremia due to Yersinia enterocolitica biogroup 4 and despite antimicrobial therapy developed a mycotic aneurysm of the left internal carotid artery. Clinical manifestations, pathogenesis, and treatment of yersiniosis are reviewed.