A 65-year-old man was referred to our hospital in April 2003 with a pancreas tumor detected by a thorough medical checkup. Computed tomography (CT) showed swelling of the pancreatic body and tail, and magnetic resonance cholangiopancreatography (MRCP) showed only the main pancreatic duct in the head of the pancreas. Diagnosing autoimmune pancreatitis, we observed the patient without medication. However, one year later CT showed stenosis of the splenic artery and portal vein accompanied by development of collateral circulation around the pancreas. He had no symptoms, and CT showed no changes in the pancreatic swelling.;;He was admitted to our hospital on January 6, 2005, presenting with a history of jaundice which first appeared on January 1, 2005, and increased collateral circulation around the pancreas with pancreatic swelling were seen on CT. We started prednisolone therapy at 40 mg/day for exacerbation of autoimmune pancreatitis. Serum bilirubin levels improved from 11.9 mg/dl to 2.5 mg/dl, and pancreatic swelling also improved four weeks after starting therapy.;;We present a rare case of autoimmune pancreatitis that developed marked collateral circulations.
X-Ray Computed Tomography ; Pancreatitis ; Collateral Circulation ; Pancreatic polypeptide, avian ; Swelling