Abdominal aorta mycotic pseudoaneurysm with rapid growth

A 53-year-old male patient with advanced-stage human immunodeficiency 1 (HIV-1), and previously treated Streptococcus infection due to an acute renal failure, was evaluated with multi-detector computed tomography (MDCT) for abdominal pain. MDCT axial and coronal images (Panels A and B) demonstrated a 3.3 cm mycotic abdominal aortic pseudoaneurysm with a subtotal thrombosis. Despite informing the patients about his vascular disease, he refused hospitalization. Fifty days later, he was admitted for acute and progressive abdominal pain. Repeat MDCT axial and coronal images (Panels C and D) showed a rapidly progressive large mycotic saccular abdominal aortic pseudoaneurysm with a maximum diameter of 12 cm. He underwent emergency endovascular treatment, with prior administration of empiric antibiotic therapy (vancomycin, piperacillin, and tazobactam) that was maintained for one month. The postoperative course was uneventful, with negative results of blood cultures. MDCT at 12 months demonstrated a complete exclusion and reduction of the abdominal aortic pseudoaneurysm.

Panels A–D.

Infected mycotic aneurysms have to be distinguished from atherosclerotic aneurysms as the former carry an extremely high risk of rupture and are associated with significant morbidity and mortality. ¹ In early cases of mycotic aneurysms, imaging studies often document focal ectasia of the involved artery, without a frankly aneurysmal dilatation. ² Since pseudoaneurysms lack a true wall, they often present as a saccular dilatation. ³ In most cases, first-line treatment is surgical excision of the pseudoaneurysm. In severe or emergency cases, endovascular stent grafts may serve as bridge or definitive therapy. ⁴

‘Images in vascular medicine’ is a regular feature of Vascular Medicine. Readers may submit original, unpublished images related to clinical vascular medicine. Submissions may be sent to: Heather Gornik, Editor in Chief, Vascular Medicine, via the web-based submission system at http://mc.manuscriptcentral.com/vascular-medicine