IDIOPATHIC FIBROSCLEROTIC DISORDERS AND OTHER INFLAMMATORY PSEUDOTUMORS

Fibroinflammatory disorders constitute heterogeneous clinical conditio ns whose cause and pathogenesis are largely unknown, Inflammatory pseu dotumor has been applied in a generic sense to several of these disord ers, which present as a mass displacing surrounding anatomic structure s or leading to organ dysfunction secondary to compressive growth arou nd the ureter(s), common bile duct, or great Vessels in the mediastinu m. The fibrosclerosing disorders of retroperitoneal fibrosis, sclerosi ng mediastinitis, sclerosing cholangitis, orbital pseudotumor, and Rie del thyroiditis are seemingly related in a clinical sense because ther e are well-documented cases of patients with two or more of these cond itions and reports of these disorders presenting in family members. Al though the pathogenesis of the fibrosclerotic disorders has not been e lucidated, autoimmunity in the context of an established collagen vasc ular disease or the setting of inflammatory periaortitis in retroperit oneal fibrosis has been one suggested mechanism. In the course of the diagnostic evaluation of an individual with a suspected fibrosclerotic disorder, it is imperative to exclude an underlying infection or mali gnancy. This caveat is especially relevant to sclerosing mediastinitis as a presentation of histoplasmosis or to retroperitoneal fibrosis se condary to a sclerosing large cell lymphoma. Sclerosing mesenteritis h as some clinical and pathological overlap with the fibrosclerotic diso rders, but its nosologic and pathogenetic relationship is uncertain at this time. There are several other fibroinflammatory processes, such as focal myositis, inflammatory fibroid polyp of the gastrointestinal tract, calcifying fibrous pseudotumor, and sclerosing peritonitis, whi ch are probably unrelated to inflammatory myofibroblastic tumor or the primary fibrosclerotic disorders. Copyright (C) 1998 by W.B. Saunders Company.