(See also Overview of Biliary Function.)
Sclerosing cholangitis may be primary (with no known cause) or secondary due to immune deficiencies (congenital in children, acquired in adults, such as AIDS cholangiopathy), often associated with superimposed infections (eg, cytomegalovirus, Cryptosporidium), histiocytosis X, or the use of drugs (eg, intraarterial floxuridine). Both primary and secondary sclerosing cholangitis cause similar inflammatory and fibrosing lesions scarring the bile ducts. Other causes of bile duct strictures are choledocholithiasis, postoperative biliary stricture, ischemic bile duct injury (during liver transplantation), congenital biliary abnormalities, cholangiocarcinoma, and parasitic infestations.
Diagnosis of biliary strictures and dilations requires imaging techniques such as ultrasonography and cholangiography.
Treatment focuses on relieving biliary obstruction (eg, dilating and stenting strictures) and, when possible, eradicating responsible organisms or treating the cause (eg, HIV).