S1464: Utility of Endoscopic Retrograde Cholangiography to Diagnose IgG4-Associated Cholangitis: an International, Double Blind, Randomized, Multicenter Study

IgG4 associated cholangitis (IAC) is a recently described condition, which is often associated with autoimmune pancreatitis, and which may have similar radiographic appearances to primary sclerosing cholangitis (PSC) and cholangiocarcinoma (CCA). Making the diagnosis is important, as IAC usually responds favorably to steroids (in contrast to PSC), and erroneous treatment for presumed CCA may be avoided. We assessed whether specialists familiar with these diseases could reliably distinguish between them, based on endoscopic retrograde cholangiograms (ERC).