2023 Volume 37 Issue 4 Pages 831-838
IgG4-related sclerosing cholangitis (IgG4-SC) is a sclerosing cholangitis characterized by elevation of serum IgG4 levels, dense infiltration of IgG4-positive plasma cells and lymphocytes, with fibrosis and obliterative phlebitis in the bile duct wall, and it is currently recognized as a biliary manifestation of a IgG4-related disease. Cholangiocarcinoma, primary sclerosing cholangitis, and pancreatic cancer are important mimickers because cholangiograms of IgG4-SC are similar to those of these mimickers. The diagnosis of IgG4-SC is based on clinical diagnostic criteria of IgG4-SC 2020. Cholangiographic classification and the association with AIP are important for the precise diagnosis of IgG4-SC in clinical diagnostic criteria of IgG4-SC 2020. Serum IgG4 level, endoscopic retrograde cholangiopancreatography, biliary intraductal ultrasonography, endoscopic bile duct biopsy, and IgG4-RD as other organ involvement are useful modalities and findings in the differential diagnosis of IgG4-SC. Isolated type IgG4-SC without AIP is sometimes difficult to discriminate from other mimickers. The clinical and radiological features of IgG4-SC are resolved by steroid therapy and the long-term prognosis is good.
