Chronic Periaortitis as a Systemic Autoimmune Disease

Abstract

Chronic periaortitis is an idiopathic disease whose hallmark is the presence of a fibro-inflammatory tissue arising from the adventitia of the abdominal aorta and the common iliac arteries and extending into the surrounding retroperitoneum and frequently encasing neighboring structures such as the ureters and the inferior vena cava (Mitchinson, 1984; Parums, 1990). It should be regarded as a generalized disease with three different pathophysiological entities, specifically idiopathic retroperitoneal fibrosis, inflammatory abdominal aortic aneurysms, and perianeurysmal retroperitoneal fibrosis (Vaglio et al., 2003; Jois et al., 2004). Idiopathic retroperitoneal fibrosis is characterized by periaortic fibroinflammatory tissue, which often causes obstruction of the ureters and other adjacent abdominal structures by extending into the retroperitoneum (Mitchinson, 1970; Gilkeson & Allen, 1996). A dilated aorta is usually not present in idiopathic retroperitoneal fibrosis. Its initial signs and symptoms are often nonspecific, such as malaise, anorexia, weight loss, fever, and flank, back, or abdominal pain. Inflammatory abdominal aortic aneurysms characteristically develop the mass around a dilated aorta, but usually do not cause obstructions (Crawford et al., 1985; Pennell et al., 1985). It usually presents with typical symptoms and signs characterized by the triad of abdominal or back pain, a pulsatile and sometimes tender abdominal mass, and an elevated erythrocyte sedimentation rate. Perianeurysmal retroperitoneal fibrosis, which represents a link between these two diagnoses, involves an abdominal aortic aneurysms surrounded by fibroinflammatory tissue that encases other abdominal organs (Serra et al, 1980). These definitions may be a little confusing, and it would probably be more appropriate to distinguish aneurysmal from nonaneurysmal forms of chronic periaortitis; idiopathic retroperitoneal fibrosis may be referred as non-aneurysmal chronic periaortitis, where as inflammatory abdominal aortic aneurysms and perianeurysmal retroperitoneal fibrosis as aneurysmal chronic periaortitis (Vaglio et al., 2006). It is important to diagnose chronic periaortitis early in its course in order to attempt to prevent the severe secondary complication of renal failure due to ureteric obstruction and the potentially fatal consequence of aortic rupture (Jois et al., 2004). Although most studies have considered these entities separately, these conditions have common clinical and histopathologic findings, and thus probably represent different manifestations of the same disease.