IgG4-Related Sclerosing Cholangitis

Autoimmune pancreatitis (AIP) is frequently associated with IgG4-related sclerosing cholangitis (IgG4-SC). The diffuse cholangiographic abnormalities observed in IgG4-SC may resemble those observed in primary sclerosing cholangitis (PSC), and the presence of segmental stenosis suggests cholangiocarcinoma (CC) (Nakazawa et al., Pancreas 30:20–25, 2005). IgG4-SC responds well to steroid therapy, whereas PSC is effectively treated only with liver transplantation, and cholangiocarcinoma requires surgical intervention. Precise diagnosis is needed before choosing appropriate treatments. This chapter provides a review of the clinical and pathological characteristics of IgG4-SC, focusing on its differential diagnosis from other biliary diseases such as PSC and CC.