Inflammatory diseases of the aorta.

Inflammatory aortic diseases may occur with and without dilatation and are complicated by obstruction, rupture and dissection. Infections originate from periaortic foci or septicaemia and tend to result in the rapid development of aneurysms. Large vessel vasculitis due to Takayasu arteritis in younger and giant cell arteritis (GCA) in older patients is located in all layers of the aortic wall and prevails in the thoracic section. GCA patients are prone to developing aortic complications in the late course of disease. In Behçet's disease, aneurysms may have an unusual morphology and localisation. The diagnosis of aortitis is usually obtained by vascular imaging, but partly made only by biopsy on occasion of an operation, especially in case of isolated aortitis of the ascending aorta which mostly remains inapparent until dissection or large aneurysms have developed. Periaortitis typically occurs in the abdominal aorta and may lead to inflammatory aortic aneurysm (IAA). It is looked upon as a special form of vasculitis, with an overlap to primary retroperitoneal fibrosis (RF). An identical pathology is discussed for the three diseases. On the other hand, about 50% of isolated aortitides and periaortitides as well as retroperitoneal fibroses can be classed among IgG4-related diseases. Periaortitis also is observed after treatment of aortic aneurysms by stent-graft implantation. Special attention should be paid to ureteral obstruction along with RF or IAA. Once infection is ruled out, immunosuppression is applied to all forms of inflammatory aortic diseases, primarily with glucocorticoids. However, after successful surgery for isolated thoracic aortitis or inflammatory aortic aneurysm immunosuppression may be dispensable and it is not required if periaortic tissue enlargement persists in chronic inactive disease. For some patients with periaortitis and RF, tamoxifen may be a valuable alternative.