title: Increased numbers of IgG4-positive plasma cells may rarely be seen in lymph nodes of patients without IgG4-related sclerosing disease.
abstract: IgG4-related sclerosing disease (IRSD) is a steroid-responsive fibroinflammatory disorder characterized by increased IgG4+ cells. Nodal involvement usually lacks the dense sclerosis seen in extranodal sites, with histologic patterns overlapping with other reactive processes. Twenty-six lymph nodes showing IRSD-related histologic patterns were evaluated for IgG and IgG4 positive cells by immunohistochemistry and correlated with the clinical features. Cases included 7 Castleman disease-like cases (type I pattern), 10 follicular hyperplasia (type II), and 9 plasmacytosis (type III). The mean numbers of IgG4+ cells per high-power field (HPF) were 4.8 (I), 8.4 (II), and 26.6(III), and the mean IgG4/IgG ratios were 0.05 (I), 0.04 (II), and 0.08 (III). Using >50 IgG4+cells/HPF and IgG4/IgG ratio of >0.4 for absolute and relative increases, only 1 case fulfilled both criteria for increased IgG4+ cells, a patient with Hashimoto's thyroiditis without clinical evidence of IRSD. The results suggest that increased IgG4+ cells may rarely be seen in non-IRSD lymph nodes.
authors.affiliation: Department of Pathology, University of Pittsburgh School of Medicine, 200 Lothrop Street-Suite G300, Pittsburgh, PA 15213, USA.
authors.forename: Marian A
authors.initials: MA
authors.lastname: Rollins-Raval
authors.forename: Raymond E
authors.initials: RE
authors.lastname: Felgar
authors.forename: Alyssa M
authors.initials: AM
authors.lastname: Krasinskas
authors.forename: Christine G
authors.initials: CG
authors.lastname: Roth
mesh_terms: D001327:Autoimmune Diseases / Q000276:immunology / Q000473:pathology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology*; D008206:Lymphatic Diseases / Q000276:immunology / Q000473:pathology*; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology*; D012598:Sclerosis / Q000276:immunology
chemical_list: D007074:Immunoglobulin G