title: [IgG4-related disease].
abstract: IgG4-related disease is a recently recognized systemic syndrome characterized by mass-forming lesions, mainly in exocrine tissue, that consist of lymphoplasmacytic infiltrates and sclerosis. There are numerous IgG4+ plasma cells in the affected tissues, and the serum IgG4 level is elevated in these patients. Ocular adnexal IgG4-related disease frequently involves bilateral lacrimal glands, and obliterative phlebitis is rare. Moreover, some malignant lymphomas, especially mucosa-associated lymphoid tissue lymphoma, arise from ocular adnexal IgG4-related disease. It is known that hyper IL-6 syndromes, such as multicentric Castleman's disease, rheumatoid arthritis, and other autoimmune diseases, fulfill the histological diagnostic criteria for IgG4-related disease; therefore, hyper IL-6 syndromes and IgG4-related disease cannot be differentially diagnosed by immunohistochemical staining alone. However, upon laboratory examination, hype IL-6 syndromes show elevation of the CRP level, polyclonal hyper gamma-globulinemia, anemia, and hypoalbuminemia. These findings are quite different from IgG4-related disease, which is not characterized by elevated serum IgA, IgM, and CRP levels. Therefore, laboratory findings are crucial for the differential diagnosis.
authors.affiliation: Department of Pathology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan. satou-y@cc.okayama-u.ac.jp
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Sato
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yoshino
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000473:pathology; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein; D005871:Castleman Disease / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood; D008223:Lymphoma / Q000175:diagnosis* / Q000473:pathology; D013577:Syndrome
chemical_list: D015415:Biomarkers; D007074:Immunoglobulin G; D015850:Interleukin-6; D002097:C-Reactive Protein