Learning objectives
• An exhibit of the multimodality US/CT/MRI/fluoroscopic imaging characteristics of autoimmune pancreatitis to aid in the differentiation of AIP from malignant pancreatic processes.
• To illustrate other extra-pancreatic imaging features.
• The role of imaging in follow up after treatment with steroids.
Background
Autoimmune pancreatitis (AIP) is the pancreatic manifestation of IgG4 related sclerosing disease which was recently recognized as distinct disease entity. Known as a benign disease process,
it can clinically mimic pancreatic cancer.
Early diagnosis and management is important as it can slowly progress to end stage pancreatic disease.
Numerous extrapancreatic organs may be involved either synchronously or metachronously.
Most cases of AIP are associated with elevated IgG4 levels; extensive IgG4 positive plasma cells; and infiltration of lymphocytes into various organs which lead to fibrosis.
It...
Imaging findings OR Procedure details
Multi-modality imaging and enhancement characteristics of pancreatic features.
Multimodality imaging of extrapancreatic pathological processes;
biliary tree dilatation
lacrimal adenitis
siladenitis
renal inflammatory pseudotumour
prostatitis
aortitis
retroperitoneal fibrosis
Follow up imaging after steroid therapy.
Pancreatic features
Autoimmune pancreatitis (AIP) is a rare form of chronic pancreatitis accounting for 1.5-11% of all cases
Pathogenesis is though to involve antibodies,
hypergammaglobulinemia and evidence of lymphoplasmocytic inflammation and fibrosis
Highly responsive to steroids
The role of imaging is to make a prompt diagnosis so that steroids can be implemented...
Conclusion
AIP is a clinical entity frequently recognized in the radiology community.
Patients often present with obstructive jaundice and can be misdiagnosed with pancreatic cancer.
It is important to recognize this disorder,
its extra-pancreatic processes and promptly commence steroid therapy to avoid end stage pancreatic disease and surgery.
A multi-modality imaging approach can support a clinical and biochemically suspected diagnosis.
References
Yoshida K,
Toki F,
Takeuchi T,
Watanabe S,
Shiratori K,
Hayashi N.
Chronic pancreatitis caused by autoimmune abnormality. Proposal of the concept of autoimmune pancreatitis.
Dig Dis Sci.
1995; 40: 1561-8.
Fujinaga Y,
Kadoya M,
Kawa S et.
al.
Characteristic findings in images of extra-pancreatic lesions association with autoimmune pancreatitis.
Eur J Radiol. 2010; 76: 228-238.
Bodily KD,
Takahashi N,
Fletcher JG et.
al.
Autoimmune pancreatitis: Pancreatic and extrapancreatic imaging findings.
AJR. 2009; 192:431-437.
Wook KS,
Suk K,
Woo JL et al. Evaluation of unusual...