Endoscopic Retrograde Cholangiography Does Not Reliably Distinguish IgG4-Associated Cholangitis From Primary Sclerosing Cholangitis or Cholangiocarcinoma

Despite high specificity of ERC for diagnosing IAC, sensitivity is poor, suggesting that many patients with IAC may be misdiagnosed with PSC or cholangiocarcinoma. Additional diagnostic strategies are likely to be vital in distinguishing these diseases.