title: Clinical significance of swollen duodenal papilla in autoimmune pancreatitis.
abstract: OBJECTIVE
  To evaluate the clinical significance of a swollen main duodenal papilla and the associated immunohistopathologic findings in patients with autoimmune pancreatitis (AIP).
  
  
  METHODS
  Seventeen consecutive patients with AIP registered between April 2001 and October 2005 who underwent both endoscopic retrograde cholangiopancreatography and endoscopic biopsy were enrolled in this study. The endoscopic features, stromal inflammatory cell infiltrate (SICI), and results of immunohistochemical examination of the duodenal papilla using IgG4, CD3, and CD79a antibodies were retrospectively reviewed. These findings in the AIP patients were compared with those in 12 patients with chronic alcoholic tumor-forming pancreatitis (CAP). The numbers of cells in the SICI and of IgG4-positive plasma cells per high-power field were counted in all the histopathologic specimens.
  
  
  RESULTS
  A swollen main duodenal papilla was observed in 11 (11 [64.7%]/17) patients with AIP and 4 (4 [33.3%]/12) patients with CAP (P < 0.05). Resolution of the swollen main duodenal papilla was observed in all of these 11 patients with AIP (11 [100%]/11) in response to treatment with corticosteroids. On the other hand, the 6 patients without elevated serum IgG4 or a swollen duodenal papilla, but with a swollen pancreas, improved even without corticosteroid treatment. The number of cells in the SICI in the AIP patients was significantly higher than that in the CAP patients. Although in 13 of 17 AIP patients, infiltration by IgG4-positive plasma cells was detected in the duodenal papilla, no such significant infiltration of the duodenal papilla by IgG4-positive plasma cells was observed in the patients with CAP (P < 0.05). More predominant T-cell infiltration of the duodenal papilla was recognized in the AIP patients than in the CAP patients (P < 0.05).
  
  
  CONCLUSIONS
  These results suggest that a swollen main duodenal papilla with IgG4-positive plasma cell and T-cell-dominant infiltration and an abundant stromal cell infiltrate are characteristic findings in AIP. We suggest that these findings may be valuable adjuncts to the diagnosis of AIP as well as for selecting suitable candidates for corticosteroid therapy.
authors: Division of Gastroenterology, Yokohama City University, Graduate School of Medicine, Yokohama, Japan. kubotak@yokohama-cu.ac.jp
authors: Kensuke
authors: K
authors: Kubota
authors: Hiroshi
authors: H
authors: Iida
authors: Toshio
authors: T
authors: Fujisawa
authors: Masami
authors: M
authors: Ogawa
authors: Masahiko
authors: M
authors: Inamori
authors: Satoru
authors: S
authors: Saito
authors: Yukio
authors: Y
authors: Kakuta
authors: Hisashi
authors: H
authors: Oshiro
authors: Atsushi
authors: A
authors: Nakajima
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000368:Aged; D014670:Ampulla of Vater / Q000276:immunology / Q000473:pathology*; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D017252:CD3 Complex / Q000032:analysis; D051925:CD79 Antigens / Q000032:analysis; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003137:Common Bile Duct Diseases / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D019512:Pancreatitis, Alcoholic / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D050500:Pancreatitis, Chronic / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D018579:Patient Selection; D010950:Plasma Cells / Q000473:pathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D017154:Stromal Cells / Q000473:pathology; D013601:T-Lymphocytes / Q000473:pathology; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones; D000893:Anti-Inflammatory Agents; D017252:CD3 Complex; D051925:CD79 Antigens; C497881:CD79A protein, human; D007074:Immunoglobulin G