title: Increased IgG4+ cells in duodenal biopsies are not specific for autoimmune pancreatitis.
abstract: Endoscopic ampullary biopsies showing increased immunoglobulin (Ig) G4+ plasma cells have been reported as an alternative to pancreatic biopsy in diagnosing autoimmune pancreatitis (AIP). This study assessed whether increased IgG4+ cells can be seen outside the context of AIP. Fifty-four cases (45 duodenal or ampullary biopsies, 9 ampullae from pancreatic resections) were selected, and all specimens were immunostained for IgG4 and IgG. Duodenal or ampullary biopsies containing normal duodenal mucosa (n = 6) and increased intraepithelial lymphocytes without villous blunting (n = 7) were negative for IgG4. Increased IgG4+ cells (>10 per high-power field) were found in 7 cases of 18 serologically confirmed celiac disease patients and in 3 of 14 patients with duodenitis or gastric heterotopias. Two of 6 ampullae from patients with pancreatic cancer showed increased IgG4+ cells. In summary, 12 of 51 patients without AIP had duodenal biopsies or ampullae showing increased IgG4+ plasma cells. The finding of increased IgG4+ cells in duodenal biopsies is not specific for AIP without the correct clinical context.
authors: San Antonio Military Medical Center, Fort Sam Houston, TX, USA.
authors: Katherine M
authors: KM
authors: Cebe
authors: Paul E
authors: PE
authors: Swanson
authors: Melissa P
authors: MP
authors: Upton
authors: Maria
authors: M
authors: Westerhoff
mesh_terms: D000328:Adult; D000368:Aged; D014670:Ampulla of Vater / Q000276:immunology / Q000473:pathology; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000276:immunology* / Q000473:pathology; D001706:Biopsy; D004386:Duodenum / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000175:diagnosis* / Q000276:immunology* / Q000473:pathology; D010950:Plasma Cells / Q000276:immunology*; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G