Diagnosis and management of autoimmune pancreatitis: experience from China.
OBJECTIVE
To determine the clinical, radiographic and pathologic characteristics, diagnostic and treatment modalities in patients with autoimmune pancreatitis (AIP).


METHODS
In this retrospective study, the data of patients with diagnosed chronic pancreatitis (CP) between 1995 and 2006 in Chinese PLA General Hospital were included to screen for the cases with AIP, according to the following diagnostic criteria: (1) diagnostic histopathologic features, and abound IgG4-positive plasma cells on pancreatic tissues; (2) characteristic imaging on computed tomography and pancreatography, together with increased serum IgG, gamma-globulin levels or presence of autoantibodies; (3) response to steroid therapy. The clinical, radiographic and pathologic characteristics, diagnostic and treatment modalities, and outcome of AIP cases were reviewed.


RESULTS
Twenty-five (22 male, 3 female; mean age 54 years, 36-76 years) out of 510 CP patients were diagnosed as AIP, which accounted for 49% (21/43) of CP population undergoing surgical treatment in the same period. The main clinical manifestations included intermittent or progressive jaundice in 18 cases (72%), abdominal pain in 11 (44%), weight loss in 10 (40%), and 3 cases had no symptoms. The imaging features consisted of pancreatic enlargement, especially in the head of pancreas (18 cases), strictures of main pancreatic duct and intrapancreatic bile duct. Massive lymphocytes and plasma cells infiltration in pancreatic tissues were showed on pathology, as well as parenchymal fibrosis. Twenty-three patients were misdiagnosed as pancreaticobiliary malignancy, and 21 patients underwent exploratory laparotomy, the remaining 4 patients dramatically responded to steroid therapy. No pancreatic cancer occurred during a mean 46-mo follow-up period.


CONCLUSIONS
AIP patients always are subjected to mistaken diagnosis of pancreatic cancer and an unnecessary surgical exploration, due to its similarity in clinical features with pancreatic cancer. The differential diagnosis with high index of suspicion of AIP would improve the diagnostic accuracy for AIP.
Song
Yang
Y
Emergency Department, Chinese PLA General Hospital, Beijing 100853, China.
Liu
Quan-Da
QD
Zhou
Ning-Xin
NX
Zhang
Wen-Zhi
WZ
Wang
Dian-Jun
DJ
D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000188:drug therapy*; D002681:China; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D050500:Pancreatitis, Chronic / Q000175:diagnosis* / Q000188:drug therapy* / Q000276:immunology; D012189:Retrospective Studies; D013256:Steroids / Q000627:therapeutic use*; D016896:Treatment Outcome
D013256:Steroids