Characteristic findings in images of extra-pancreatic lesions associated with autoimmune pancreatitis.
OBJECTIVE
Autoimmune pancreatitis is a unique form of chronic pancreatitis characterized by a variety of extra-pancreatic involvements which are frequently misdiagnosed as lesions of corresponding organs. The purpose of this study was to clarify the diagnostic imaging features of extra-pancreatic lesions associated with autoimmune pancreatitis.


METHODS
We retrospectively analyzed diagnostic images of 90 patients with autoimmune pancreatitis who underwent computer-assisted tomography, magnetic resonance imaging, and/or gallium-67 scintigraphy before steroid therapy was initiated.


RESULTS
AIP was frequently (92.2%) accompanied by a variety of extra-pancreatic lesions, including swelling of lachrymal and salivary gland lesions (47.5%), lung hilar lymphadenopathy (78.3%), a variety of lung lesions (51.2%), wall thickening of bile ducts (77.8%), peri-pancreatic or para-aortic lymphadenopathy (56.0%), retroperitoneal fibrosis (19.8%), a variety of renal lesions (14.4%), and mass lesions of the ligamentum teres (2.2%). Characteristic findings in CT and MRI included lymphadenopathies of the hilar, peri-pancreatic, and para-aortic regions; wall thickening of the bile duct; and soft tissue masses in the kidney, ureters, aorta, paravertebral region, ligamentum teres, and orbit.


CONCLUSIONS
Recognition of the diagnostic features in the images of various involved organs will assist in the diagnosis of autoimmune pancreatitis and in differential diagnoses between autoimmune pancreatitis-associated extra-pancreatic lesions and lesions due to other pathologies.
Fujinaga
Yasunari
Y
Department of Radiology, Shinshu University School of Medicine, Asahi, Matsumoto, Japan. fujinaga@shinshu-u.ac.jp
Kadoya
Masumi
M
Kawa
Shigeyuki
S
Hamano
Hideaki
H
Ueda
Kazuhiko
K
Momose
Mitsuhiro
M
Kawakami
Satoshi
S
Yamazaki
Sachie
S
Hatta
Tomoko
T
Sugiyama
Yukiko
Y
D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases / Q000150:complications* / Q000175:diagnosis*; D002908:Chronic Disease; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000150:complications* / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000150:complications* / Q000175:diagnosis*