(See also Overview of Biliary Function Overview of Biliary Function The liver produces about 500 to 600 mL of bile each day. Bile is isosmotic with plasma and consists primarily of water and electrolytes but also organic compounds: bile salts, phospholipids... read more .)
Sclerosing cholangitis may be primary Primary Sclerosing Cholangitis (PSC) Primary sclerosing cholangitis (PSC) is patchy inflammation, fibrosis, and strictures of the bile ducts that has no known cause. However, 80% of patients also have inflammatory bowel disease... read more (with no known cause) or secondary due to immune deficiencies (congenital in children, acquired in adults, such as AIDS cholangiopathy AIDS Cholangiopathy AIDS cholangiopathy is biliary obstruction secondary to biliary tract strictures caused by various opportunistic infections. (See also Overview of Biliary Function.) Before the advent of antiretroviral... read more ), often associated with superimposed infections (eg, cytomegalovirus Cytomegalovirus (CMV) Infection Cytomegalovirus (CMV, human herpesvirus type 5) can cause infections that have a wide range of severity. A syndrome of infectious mononucleosis that lacks severe pharyngitis is common. Severe... read more , 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 Choledocholithiasis and Cholangitis Choledocholithiasis is the presence of stones in bile ducts; the stones can form in the gallbladder or in the ducts themselves. These stones cause biliary colic, biliary obstruction, gallstone... read more , postoperative biliary stricture, ischemic bile duct injury (during liver transplantation), congenital biliary abnormalities, cholangiocarcinoma Tumors of the Gallbladder and Bile Ducts Gallbladder and bile duct tumors can cause extrahepatic biliary obstruction. Symptoms may be absent but often are constitutional or reflect biliary obstruction. Diagnosis is based on ultrasonography... read more , and parasitic infestations.
Diagnosis of biliary strictures and dilations requires imaging techniques Imaging Tests of the Liver and Gallbladder Imaging is essential for accurately diagnosing biliary tract disorders and is important for detecting focal liver lesions (eg, abscess, tumor). It is limited in detecting and diagnosing diffuse... read more 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).