Abstract
A 59-year-old male patient had developed obstructive jaundice and was admitted to the Department of Surgery, Soka Municipal Hospital for further diagnosis and treatment. He had the history of being suspected to have diabetes mellitus because of hyperglycemia three years before, but had no history of autoimmune diseases. A physical examination on admission revealed jaundice, but no other abnormal findings. Abdominal CT scan and MRI showed slight swelling of the entire pancreas. Percutaneous transhepatic cholangiography (PTC) showed complete obstruction of the common bile duct in the intrapancreatic portion, with proximal dilatation. Endoscopic retrograde pancreatography (ERP) showed irregular stenosis of the main pancreatic duct in the head and tail of the pancreas. The result of the cytology of the bile juice was Class IIIb. Preoperative diagnosis was common bile duct cancer and pancreaticoduodenectomy was employed. Histological examination of surgical specimen showed severe chronic inflammatory cells infiltration and fibrosis in the pancreas but no cancer cells were observed. Serum IgG4 level four months after operation was as high as 4,400mg/L. The patient was conclusively diagnosed as having autoimmune pancreatitis. It is very important to be well aware of the possibility of the autoimmune panceatitis presenting obstructive jaundice in order to avoid unnecessary operation.
