IgG4-negative autoimmune pancreatitis with sclerosing cholangitis and colitis: possible association with primary sclerosing cholangitis?

We report a case of autoimmune pancreatitis (AIP) with cholangiography and histopathology showing features characteristic of primary sclerosing cholangitis (PSC) and colitis. A 55-year-old previously-healthy man was diagnosed with anti-nuclear antibody (ANA)-positive AIP according to the finding of serum biochemistry, abdominal US (ultrasonography), CT (computed tomography) and ERCP (endoscopic retrograde cholangiopancreatography). However, bead-like strictures of intrahepatic bile ducts were also found and liver tissue showed onion skin-like periductal fibrosis but no anti-IgG4-positive cells. In addition, colon fiberscopy showed a pancolitis similar to ulcerative colitis indicating that, in this case, there may be an association with PSC. Here, we report a rare case of IgG4-negative AIP with sclerosing cholangitis and colitis with many clinical features that support an association with PSC.