Involvement of the biliary system in autoimmune pancreatitis: a follow-up study.
OBJECTIVE
The aim of this study was to define the bile duct changes associated with autoimmune pancreatitis.


METHODS
Eight patients with autoimmune pancreatitis were followed for a mean of 4 years. The clinical features of these patients, including extrapancreatic bile duct changes, were examined by using biochemical parameters and several imaging modalities. Pathologic features of the pancreas and liver were examined by using the biopsy specimens of 7 patients.


RESULTS
Diffuse or focal narrowing of the main pancreatic duct was observed in all patients. Histologic examination of the pancreas showed lymphoplasmacyte infiltration with severe fibrosis and acinar cell depletion. In 6 patients extrapancreatic bile duct changes such as stricture of the bile duct at hilus or intrahepatic area were observed. In 2 patients abnormalities in the bile duct and pancreas were detected simultaneously at diagnosis, and changes in the bile duct were observed later in 4 patients. Lymphoplasmacyte infiltration and fibrosis were observed in the portal area of all 7 liver biopsy samples. Five of the patients with bile duct changes received steroid therapy, and the pathological changes improved.


CONCLUSIONS
Extrapancreatic bile duct changes are frequently associated with autoimmune pancreatitis. Similar pathogenic mechanism might produce the biliary tract and pancreatic abnormalities in autoimmune pancreatitis resulting in a similar histopathology in the liver and pancreas and response to steroid therapy.
Hirano
Kenji
K
Department of Gastroenterology, University of Tokyo, Japan. khirano-tky@umin.ac.jp
Shiratori
Yasushi
Y
Komatsu
Yutaka
Y
Yamamoto
Natsuyo
N
Sasahira
Naoki
N
Toda
Nobuo
N
Isayama
Hiroyuki
H
Tada
Minoru
M
Tsujino
Takeshi
T
Nakata
Ryo
R
Kawase
Tateo
T
Katamoto
Tetsuo
T
Kawabe
Takao
T
Omata
Masao
M
D000368:Aged; D000469:Alkaline Phosphatase / Q000187:drug effects / Q000378:metabolism; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy; D017734:Bile Ducts, Extrahepatic / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D015415:Biomarkers / Q000097:blood; D001707:Biopsy, Needle; D002908:Chronic Disease; D004322:Drainage; D016145:Endoscopy, Digestive System; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D010186:Pancreatic Function Tests; D010195:Pancreatitis / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy; D011239:Prednisolone / Q000627:therapeutic use; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional; D005723:gamma-Glutamyltransferase / Q000187:drug effects / Q000378:metabolism
D000893:Anti-Inflammatory Agents; D015415:Biomarkers; D011239:Prednisolone; D005723:gamma-Glutamyltransferase; D000469:Alkaline Phosphatase