ABSTRACT
Autoimmune pancreatitis (AIP) is a form of chronic pancreatitis characterized by an autoimmune inflammatory process. This is the first case report of AIP, not otherwise specified, accompanied by pericardial effusion. A 52-year-old female visited our hospital due to dyspnea. Echocardiography showed a large amount of pericardial thickening. Abdominal computed tomography revealed diffuse enlargement of the pancreas body and tail with a sausage-shaped appearance, surrounded by a thick hypodense rim. Endoscopic retrograde cholangiopancreatography could not identify the tail portion of the pancreas, despite forceful contrast injection. Serology was positive for antinuclear antibody and IgG4 was normal. Endoscopic ultrasound-guided core biopsy of the pancreas was performed. Histologic examination revealed a fibrous connective tissue with inflammatory infiltration. The patient was treated with steroids. In the follow-up images, abnormal findings of pericardial effusion were improved, although an irregular long stricture of the pancreas tail portion remained.