Close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.
BACKGROUND
Autoimmune pancreatitis is a unique clinical entity proposed recently, and is sometimes associated with inflammation of other organs.


OBJECTIVE
To examine the pathophysiology of the pancreas and other organs in patients with autoimmune pancreatitis.


METHODS
We evaluated clinicopathological findings in six resected and one autopsied patient with autoimmune pancreatitis. The pancreas, peripancreatic tissue, bile duct, and gall bladder were examined histologically and immunohistochemically. Biopsied salivary gland and cervical lymph node of one patient were also examined. We also performed similar immunohistochemical examinations in pancreatectomy specimens from 10 patients with alcoholic chronic pancreatitis and biopsied salivary glands from five patients with Sjögren's syndrome.


RESULTS
Stenosis of the extrahepatic bile duct was detected in all patients. Histological findings were characterised by diffuse lymphoplasmacytic infiltration with marked interstitial fibrosis and acinar atrophy, obliterated phlebitis of the pancreatic veins, and involvement of the portal vein. Immunohistochemically, diffusely infiltrating cells consisted predominantly of CD4 or CD8 positive T lymphocytes and IgG4 positive plasma cells. Similar inflammatory processes also involved the peripancreatic tissue, extrahepatic bile duct, gall bladder, and salivary gland. Lymph nodes were swollen with infiltration of IgG4 positive plasma cells. None of these findings was seen in alcoholic chronic pancreatitis or Sjögren's syndrome.


CONCLUSIONS
The development of the specific inflammations in extensive organs as well as the pancreas in patients with autoimmune pancreatitis strongly suggests a close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.
Kamisawa
T
T
Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan. kamisawa-k@komagome-hospital.bunkyo.tokyo.jp
Funata
N
N
Hayashi
Y
Y
Tsuruta
K
K
Okamoto
A
A
Amemiya
K
K
Egawa
N
N
Nakajima
H
H
D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D001327:Autoimmune Diseases / Q000276:immunology / Q000473:pathology*; D001652:Bile Ducts / Q000276:immunology / Q000473:pathology; D002908:Chronic Disease; D003251:Constriction, Pathologic; D005260:Female; D005355:Fibrosis; D005704:Gallbladder / Q000276:immunology / Q000473:pathology; D006680:HLA Antigens / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D010179:Pancreas / Q000276:immunology / Q000473:pathology*; D010195:Pancreatitis / Q000276:immunology / Q000473:pathology*; D012469:Salivary Glands / Q000276:immunology / Q000473:pathology; D012598:Sclerosis; D013601:T-Lymphocytes / Q000276:immunology
D015703:Antigens, CD; D006680:HLA Antigens