Type 2 autoimmune pancreatitis: case report of a 9-year-old female and a review of the literature.

We report a case of autoimmune pancreatitis in a 9-year-old female who presented with persistent epigastric pain for 3 weeks. Magnetic resonance cholangiopancreatography (MRCP) showed both intrahepatic and extrahepatic biliary ductal dilatation. The common bile duct, along with the pancreatic duct, was noted to be dilated. Labs showed normal IgG and IgG4 levels and negative for autoimmune antibodies. Endoscopic ultrasound revealed the pancreatic head to be enlarged and surrounded by hypoechoic and lobulated lymph nodes. Biopsy of the pancreatic head showed chronic mildly active inflammation with fibrosis, acinar atrophy, and lymphocytic infiltrate. A diagnosis of autoimmune pancreatitis (AIP) was made, and she was treated with prednisone. The patient's symptoms improved quickly, and follow-up MRCP showed resolution of inflammatory changes and intrahepatic and pancreatic ductal dilatation.