Long-term outcome of autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a unique form of pancreatitis and can be complicated with various extrapancreatic lesions. Little is known about the long-term clinical course of AIP. Here we aimed to document the clinical course of AIP.

For this study, we recruited 21 patients, averaging 66.5 years in age (range, 19-84 years) and observed them at a mean interval of 40.8 months (range, 18-130 months). Three of the patients were also diagnosed with retroperitoneal fibrosis, 3 had sialoadenitis, 2 had chronic thyroiditis, 1 had interstitial nephritis, and 1 had interstitial pneumonia. Three of the patients underwent surgical therapy, 12 patients received methylprednisolone (PSL) treatment, and the 6 remaining patients received no treatment.

Enlargement of the pancreas was attenuated in all the PSL-treated patients. Seven of the 21 patients showed pancreatic atrophy, of whom 2 were non-PSL-treated patients. Three patients developed chronic pancreatitis. One patient was diagnosed with pancreatic cancer after 50 months of PSL therapy.

As with chronic pancreatitis patients, AIP patients should be observed closely for abnormality in pancreatic function.