Autoimmune pancreatitis is a distinct form of chronic pancreatitis, characterized clinically by frequent presentation with obstructive jaundice with or without a pancreatic mass, histologically by a lymphoplasmacytic infiltrate and fibrosis and therapeutically by a dramatic response to steroids [1]. Although the pathogenesis of AIP remains unclear, an immune-mediated mechanism has been postulated. This disease typically affects males without a history of alcohol abuse, biliary stone disease, or duodenal wall inflammation. This is supported by the remission of the signs and symptoms related to pancreatic inflammation...

This retrospective study was approved by the investigational review board, and the requirement for informed patient consent was waived. A search of our institution’s histopathology, radiology, and medical records for the period between February 2001 and October 2011 revealed 130 patients with AIP. Patient data were included according to the following criteria: (a) clinical diagnosis of AIP based on fulfillment of Italian diagnostic criteria for AIP, (b) histopathologically proved AIP, (c) radiological diagnosis of focal form of PAI and (d) availability of MR examination findings....

OBSERVATIONS AT DIAGNOSIS Qualitative image analysis Anatomical malformations of the pancreatic ductal system: the presence of pancreas divisum was observed in 2/37 (5,4%) patients. Site of pancreatic lesions and signal intensity of the parenchima: signal intensity abnormalities and focal enlargement of pancreatic parenchyma was localized in the head in 18/37 (48,6%) cases and in the body-tail in 19/37 (51,4%) patients (Table 2). Contrast enhancement of pancreatic parenchyma: the lesion appeared hypointense in T1-weighted images and lightly hyperintense in T2-weighted images in all cases; thus, after...

The focal form of autoimmune pancreatitis is an emerging disease, diagnosed more frequently in response to a request for an in-depth radiological analysis in patients with acute pancreatitis or abdominal pain not well characterized. All patients in our study showed significant response to steroid treatment, evaluated with the remission of symptoms and improvement or complete resolution of radiological patterns. MRI, thanks to its elevated high contrast resolution, shows pancreatic abnormalities suggestive of AIP and allows to evaluate the response to treatment and the presence of...

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