Inflammatory abdominal aortic aneurysm (AAA) accounts for 5% to 10% of all cases of AAA and differs from typical atherosclerotic AAA in many important ways. Although both inflammatory and atherosclerotic AAA most commonly affect the infrarenal portion of the abdominal aorta, patients with the inflammatory variant are younger and usually symptomatic, chiefly from back or abdominal pain. Unlike patients with atherosclerotic AAA, most with the inflammatory variant have an elevated erythrocyte sedimentation rate or abnormalities of other serum inflammatory markers. Computed tomography and magnetic resonance imaging are both sensitive for demonstrating the cuff of soft tissue inflammation surrounding the aneurysm that is characteristic of inflammatory AAA. In contrast to atherosclerotic AAA, the inflammatory variant is characterized pathologically by marked thickening of the aneurysm wall, fibrosis of the adjacent retroperitoneum, and rigid adherence of the adjacent structures to the anterior aneurysm wall. An extraordinary expansion of the adventitia due to inflammation also distinguishes inflammatory from atherosclerotic AAA. Although the pathogenesis of inflammatory AAA appears to involve an immune response localized to the vessel wall, the etiology of the inflammatory reaction is unknown. Inflammatory AAA is almost never associated with inflammation of other arteries. Male sex and smoking, the main risk factors for atherosclerotic AAA, are even stronger risk factors for the inflammatory variant. Smoking cessation is the first step of medical therapy. Corticosteroids or immunosuppressive therapies may also have roles. Although inflammatory AAA appears less likely to rupture than atherosclerotic AAA, surgical intervention appears prudent once the diameter of the aneurysm exceeds 5.5 cm. Knowing the features of inflammatory AAA should allow physicians to distinguish it from atherosclerotic AAA or from systemic vasculitis and to treat it with the appropriate combination of medical and surgical therapies.
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Purchase Online Access to this article for 24 hours
In these CT images of an infrarenal inflammatory abdominal aortic aneurysm, the lumen of the aorta is opacified with contrast (white), and the gray area on either side of the lumen is thickened aortic wall. Nodular thickening of the aortic wall infiltrates the perianeurysmal fat (most apparent in the left panel). The right panel demonstrates the diffuse nature of aortic involvement.
Image obtained after anti-inflammatory treatment demonstrates a fusiform aortic aneurysm without evidence of significant wall thickening or periaortic inflammation.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 34
Customize your page view by dragging & repositioning the boxes below.
More Listings atJAMACareerCenter.com >
Users' Guides to the Medical Literature
Abdominal Aortic Aneurysm
The Rational Clinical Examination
Make the Diagnosis: Abdominal Aortic Aneurysm
All results at
and access these and other features:
Enter your username and email address. We'll send you a link to reset your password.
Enter your username and email address. We'll send instructions on how to reset your password to the email address we have on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.