[Chronic periaortitis].

Chronic periaortitis is a rare fibroinflammatory disorder which affects the abdominal aorta and may spread into the retroperitoneum, often encasing the ureters. An aneurysma of the abdominal aorta and vasculitis of the thoracic aorta and of supra-aortic vessels may also coexist. Chronic periaortitis can be idiopathic or secondary to different triggers such as drugs, tumors and infections. Abdominal and/or low back pain is the hallmark symptom. Laboratory markers of inflammation are usually increased. The diagnosis rests on computerized tomography or magnetic resonance imaging, which typically show a retroperitoneal mass displacing the aorta anteriorly and the ureters medially. Positron-emission tomography may assist in defining disease activity and extension. Chronic periaortitis should be differentiated from other fibrosing disorders of various origins. Histology is required in atypical cases to secure the diagnosis. Treatment is based on high-dose steroids with a tapering scheme combined with immunosuppressive agents in refractory or relapsing disease. In case of ureter obstruction early DJ-catheter placement is required. Operative interventions to relieve ureter obstruction are rarely necessary provided immunosuppressive treatment is timely instituted.