Sclerosing cholangitis may mimic radiological pattern of cholangiocarcinoma: Differential diagnosis and review of literature.

IgG4 related sclerosing cholangitis (IgG4-SC) is a chronic cholestatic autoimmune liver disease, characterized by obstruction of the biliary tract due to IgG4-positive plasma cell infiltrations associated with fibrosis, phlebitis and presence of eosinophils. The diagnosis of the disease is supported by elevation in serum IgG4, radiological imaging and histology. In most of the cases IgG4-SC is associated with a wide spectrum of symptoms and manifestations summarized by the definition of IgG4-related disease (IgG4-RD). When the IgG4-SC causes an interruption of the biliary tract, differential diagnosis with cholangiocarcinoma may become challenging, due to the anatomical difficulty to get an appropriate histological pattern of the disease. Here we are describing a case of a male patient admitted to our hospital for jaundice. The stenosis of biliary ducts shown by radiologic imaging suggested Cholangiocarcinoma but, in the patient, IgG4-SC was definitely diagnosed.