Abstract
IgG4-related sclerosing cholangitis (IgG4-SC) is a sclerosing cholangitis characterized by increased levels of serum IgG4, dense infiltration of IgG4-positive plasma cells in the bile duct wall, and a good response to steroid therapy. The concept of IgG4-SC recently has been recognized as that of IgG4-related diseases, and the Clinical Diagnostic Criteria of IgG4-SC 2012 was established in Japan. The diagnosis of IgG4-SC is based on the combination of the following 4 criteria : (1) characteristic biliary imaging findings, (2) elevation of serum IgG4 concentrations, (3) coexistence of IgG4-related diseases except for those of the biliary tract, and (4) characteristic histopathological features. Primary sclerosing cholangitis, cholangiocarcinoma and pancreatic cancer are very important diseases to consider in the differential diagnosis of IgG4-SC. Endoscopic retrograde cholangiopancreatography, biliary intraductal ultrasonography, endoscopic ultrasonography and colonoscopy are useful modalities for the acquisition of images. Endoscopic bile duct biopsy and endoscopic ultrasonography-guided fine-needle aspiration are useful modalities for endoscopic biopsy procedures. We review endoscopic procedures in the diagnosis of IgG4-SC on the basis of Clinical Diagnostic Criteria of IgG4-SC 2012.
