Journal of Gastroenterology

, Volume 41, Issue 12, pp 1197–1205

Prevalence and distribution of extrapancreatic lesions complicating autoimmune pancreatitis

  • Hideaki Hamano
  • Norikazu Arakura
  • Takashi Muraki
  • Yayoi Ozaki
  • Kendo Kiyosawa
  • Shigeyuki Kawa
Article

DOI: 10.1007/s00535-006-1908-9

Cite this article as:
Hamano, H., Arakura, N., Muraki, T. et al. J Gastroenterol (2006) 41: 1197. doi:10.1007/s00535-006-1908-9

Abstract

Background

Autoimmune pancreatitis is a unique form of chronic pancreatitis characterized by high serum IgG4 concentrations and abundant IgG4-bearing plasma cell infiltration in the pancreatic lesion, and it has been reported to be associated with a variety of extrapancreatic lesions, leading us to postulate the concept of a systemic inflammatory disease. To confirm this, we clarified the exact distribution of these extrapancreatic lesions and provide a panoramic view of them.

Methods

The frequency, distribution, clinical characteristics, and pathology of five extrapancreatic lesions were determined in 64 patients with autoimmune pancreatitis by examining clinical and laboratory findings.

Results

The most frequent extrapancreatic lesion was hilar lymphadenopathy (80.4%), followed by extrapancreatic bile duct lesions (73.9%), lachrymal and salivary gland lesions (39.1%), hypothyroidism (22.2%), and retroperitoneal fibrosis (12.5%). No patients had all five types of lesions. Patients with hilar lymphadenopathy or lachrymal and salivary gland lesions were found to have significantly higher IgG4 levels than those without (P = 0.0042 and 0.0227, respectively). Patients with three lesions were found to have significantly higher IgG4 levels than those with no lesion, suggesting that patients with multiple extrapancreatic lesions have active disease. Similar to pancreatic lesions, extrapancreatic lesions have a characteristic histological finding of abundant IgG4-bearing plasma cell infiltration, and they respond favorably to corticosteroid therapy.

Conclusions

Autoimmune pancreatitis was recognized as a systemic inflammatory disease. Furthermore, recognition of these characteristic findings will aid in the correct diagnosis of this disease.

Key words

autoimmune pancreatitisIgG4extrapancreatic lesionsystemic inflammatory disease

Copyright information

© Springer-Verlag Tokyo 2006

Authors and Affiliations

  • Hideaki Hamano
    • 1
  • Norikazu Arakura
    • 1
  • Takashi Muraki
    • 1
  • Yayoi Ozaki
    • 1
  • Kendo Kiyosawa
    • 1
  • Shigeyuki Kawa
    • 2
  1. 1.Department of Medicine, GastroenterologyShinshu University School of MedicineMatsumotoJapan
  2. 2.Center for Health, Safety and Environmental ManagementShinshu UniversityMatsumotoJapan