Mis-diagnosis and mis-treatment of autoimmune pancreatitis: a clinical study of 17 cases

Abstract

Objective To summarize the reasons of mis-diagnosis and mis-treatment of autoimmune pancreatitis (AIP). Methods Clinical data of 17 patients with AIP,who were admitted to the hospital from May 2005 to July 2010 and experienced mis-diagnosis and mis-treatment, were retrospectively analyzed. Results The main clinical manifestations included epigastric pain (13 cases),progressive obstructive jaundice (12 cases), fever (6 cases) and weight loss (9 cases). Fifteen patients had extrapancreatic organ involvemnet, including allergic rhinitis, swelling of lymphoglandulae submaxillares, swelling of submaxillary gland, allergic asthma, rheumatoid arthritis, Sjogren syndrome, diabetes mellitus, primary sclerosing cholangitis and autoimmune hepatitis. Of these 17 cases, 11 cases presented with high serum globulin, 14 cases with high serum IgG, 13 cases with high serum γ-globulin, 13 cases with positive anti-nuclear antibody and 2 cases with positive anti-insulin IgG antibody. The abdominal imaging demonstrated that 15 patients had diffuse enlargement of the pancreas with diffuse or segmental narrowing of main pancreatic duct, narrowing of the intrapancreatic common bile duct, dilation of the proximal biliary duct and gallbladder enlargement. Focal enlargement of the pancreas was found in 2 cases. Thirteen cases were misdiagnosed as pancreatic carcinoma. Among them, 4 cases underwent pancreaticoduodenectomy and 7 cases underwent choledochojejunostomy. Two cases were misdiagnosed as end stage of cancer that lost therapeutic chance. Another 4 cases were misdiagnosed as chronic pancreatitis. Steroid therapy was administered in all patients with satisfactory response. All patients were followed-up for 15 months (ranged from 6 months to 45 months), and recurrence was found in 4 cases. Satisfactory response was found in patients treated with steroid for the second time. No pancreatic cancer was found in these patients in the follow up period. Conclusion The main causes of mis-diagnosis and mis-treatment of AIP may be contributed by difficulty in differentiating AIP from pancreatic carcinoma based on clinical manifestations and inadequate knowledge of AIP as well as insufficient attention to AIP in China. Key words: Pancreatitis; Autoimmune diseases; Diagnostic errors; Therapeutic errors