hepatic and biliary disorders
IgG4 Related Sclerosing Cholangitis
Diagnosis of IgG4 SC
Cholangiogram IgG4 levels Histology tests IgG4-SC should be considered particularly in patients with pancreatitis plus cholangiopathy. Accurate differentiation of IgG4-SC from other forms of sclerosing cholangitis is critical because IgG4-SC requires different treatment and confers favorable outcomes. Diagnosis requires an atypical cholangiogram, elevated IgG4 levels (in most, but not all, patients) and representative histological features, including a diffuse lymphoplasmacytic infiltrate enriched in IgG4-positive plasma cells of both intra- and extra-hepatic bile duct walls, storiform (“cartwheel”) fibrosis, and preserved bile duct epithelial layer. Particularly in older patients, IgG4-SC can be misdiagnosed as hepatobiliary malignancy. 