title: Immunoglobulin G4-Related Lymphadenopathy.
abstract: Immunoglobulin G4-related lymphadenopathy (IgG4-RLAD) occurs in the setting of extranodal IgG4-related disease (IgG4-RD), an immune-mediated process described in many organ systems characterized by lymphoplasmacytic infiltrates with abundant IgG4-positive plasma cells and fibrosis. Although the morphologic features in the lymph node sometimes resemble those seen at the extranodal sites, 5 microscopic patterns have been described, most of which resemble reactive lymphoid hyperplasia. This morphologic variability leads to unique diagnostic challenges and a broad differential diagnosis. As IgG4-RD may be exquisitely responsive to steroids or other immunotherapy, histologic recognition and inclusion of IgG4-RLAD in the differential diagnosis is vital.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina, Campus Box 7525, Brinkhous-Bullitt Building, Chapel Hill, NC 27599-7525, USA.
authors.forename: Christine E
authors.initials: CE
authors.lastname: Bookhout
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina, Campus Box 7525, Brinkhous-Bullitt Building, Chapel Hill, NC 27599-7525, USA. Electronic address: Marian_Raval@med.unc.edu.
authors.forename: Marian A
authors.initials: MA
authors.lastname: Rollins-Raval
mesh_terms: D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D001706:Biopsy; D003937:Diagnosis, Differential; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008198:Lymph Nodes / Q000473:pathology; D000072281:Lymphadenopathy / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D008223:Lymphoma / Q000175:diagnosis; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology; D011379:Prognosis
chemical_list: D007074:Immunoglobulin G
keywords: IgG4; IgG4-related disease; Immunohistochemistry; Lymphadenopathy; Lymphoma