[Mycotic Aneurysm of the Ulnar Artery Associated with Infective Endocarditis;Report of a Case].

A 19-year-old man, with a history of hospitalization for infective endocarditis associated with Streptococcus mitis/oralis 2 months before, was admitted to our hospital because of stomach ache and pulsatile mass on the left forearm. Computed tomography(CT) and ultrasonography revealed a thrombus in the superior mesenteric artery and an aneurysm of the left ulnar artery. As vegetation was noted on the anterior leaflet of the mitral valve, mitral valve replacement and ulnar artery aneurysmorrhaphy were performed. He was discharged 24 days after surgery without any complications. Although mycotic aneurysm is one of the complications of infective endocarditis, it is rarely formed in the ulnar artery. Moreover, mycotic aneurysm may develop even after inflammatory reaction has subsided. Thus, longterm observation of patients with infective endocarditis is necessary.