title: Autoimmune pancreatitis associated with a large pancreatic pseudocyst that disappeared after corticosteroid therapy: a case report and literature review.
abstract: A 51-year-old woman was admitted to our department because of upper abdominal pain. The serum IgG4 concentration was elevated, and abdominal computed tomography revealed diffuse enlargement of the pancreas associated with a large cyst, measuring 8 cm in diameter. Endoscopic retrograde cholangiopancreatography revealed narrowing of the main pancreatic duct (from the body to the tail), narrowing of the intrapancreatic bile duct, and dilatation of the bile ducts. The patient was given a diagnosis of autoimmune pancreatitis (AIP) associated with a pancreatic pseudocyst and intrapancreatic bile duct stenosis. Oral steroid therapy resulted in reduced pancreatic swelling, complete disappearance of the pancreatic cyst, and an improvement in biliary stenosis. AIP is rarely associated with pancreatic cyst, and only 13 cases, including ours, have been reported to date. In our patient, intense inflammation apparently led to cyst formation in association with AIP, which responded remarkably to corticosteroid therapy. Correct diagnosis of AIP associated with a pancreatic pseudocyst might save patients from undergoing unnecessary endoscopic and surgical procedures.
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan. naoyukin@jichi.ac.jp.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Nishimura
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Kiichi
authors.initials: K
authors.lastname: Tamada
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Wada
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ohashi
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hatanaka
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Nakazawa
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Norikatsu
authors.initials: N
authors.lastname: Numao
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Kitamura
authors.affiliation: Department of Endoscopy, Jichi Medical University, Shimotsuke, Japan.
authors.forename: Kiichi
authors.initials: K
authors.lastname: Satoh
authors.affiliation: Department of Fujinon International Optics, Jichi Medical University, Shimotsuke, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Department of Gastroenterology and Hepatology, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Sugano
keywords: Autoimmune pancreatitis; Corticosteroid; Pseudocyst