title: Rethinking Ormond's disease: "idiopathic" retroperitoneal fibrosis in the era of IgG4-related disease.
abstract: Idiopathic retroperitoneal fibrosis (RPF) is a periaortic sclerotic disease that encases adjacent retroperitoneal structures, particularly the ureters. A subset of idiopathic RPF cases can be associated with IgG4-related disease, but the frequency of this association is not clear. We selected 23 cases of idiopathic RPF and identified IgG4-related RPF cases based on the presence of IgG4+ plasma cells in the tissue, using an IgG4/IgG ratio cutoff of >40%. We then compared the IgG4-related RPF patients and the non-IgG4-related RPF patients in terms of both the presence of histopathologic features typical of IgG4-related disease and the simultaneous occurrence (or history) of other organ manifestations typical of IgG4-related disease. The IgG4-related RPF and non-IgG4-related RPF groups were also analyzed in terms of clinical, laboratory, and radiologic features and treatment review. We identified 13 cases of IgG4-related RPF (57% of the total cohort). The distinguishing features of IgG4-related RPF were histopathologic and extra-organ manifestations of IgG4-related disease. The IgG4-related RPF patients were statistically more likely than non-IgG4-related RPF patients to have retroperitoneal biopsies showing lymphoplasmacytic infiltrate (p = 0.006), storiform fibrosis (p = 0.006), or tissue eosinophilia (p = 0.0002). Demographics of the 2 groups, including a middle-aged, male predominance (mean age, 58 yr; 73% male), were similar. IgG4-related disease accounts for a substantial percentage of patients with "idiopathic" RPF. Histopathologic features such as storiform fibrosis, obliterative phlebitis, and tissue eosinophilia are critical to identifying this disease association. Extraretroperitoneal manifestations of IgG4-related disease are also often present among patients with IgG4-related RPF. Elevated IgG4/total IgG ratios in tissue biopsies are more useful than the number of IgG4+ plasma cells per high-power field in cases of RPF that are highly fibrotic.
authors: From Rheumatology Unit (AK, MNC, JHS), Division of Rheumatology, Allergy, and Immunology, Department of Medicine; Department of Pathology (SS, RPH, VD); and Department of Radiology (NS), Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
authors: Arezou
authors: A
authors: Khosroshahi
authors: Mollie N
authors: MN
authors: Carruthers
authors: John H
authors: JH
authors: Stone
authors: Shweta
authors: S
authors: Shinagare
authors: Nisha
authors: N
authors: Sainani
authors: Robert P
authors: RP
authors: Hasserjian
authors: Vikram
authors: V
authors: Deshpande
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012185:Retroperitoneal Fibrosis / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D012187:Retroperitoneal Space / Q000473:pathology; D012189:Retrospective Studies
chemical_list: D007074:Immunoglobulin G