(See also Overview of Blood Vessel Disorders of the Liver.)
Bile ducts (such as the hepatic ducts and the common bile duct), unlike the liver, are supplied with blood from only one major blood vessel, the hepatic artery. Thus, disruption of blood flow through the hepatic artery can prevent the bile ducts from obtaining enough oxygen. Consequently, the cells lining the ducts are damaged or die—a disorder called ischemic cholangiopathy. Blood flow can be disrupted when
A liver transplant is rejected.
Blood vessels are injured during liver transplantation surgery or removal of the gallbladder by laparoscopy.
Blood vessels are injured by radiation therapy.
People have a disorder that makes blood more likely to clot (blood clotting disorder).
A procedure that is done to block blood flow to a tumor in the liver (called chemoembolization) also blocks blood flow to healthy tissue.
Ischemic cholangiopathy most commonly occurs in people who have had a liver transplant.
The damaged bile duct becomes inflamed, narrows (causing a stricture), or both. Then the flow of bile slows or is blocked. If bile cannot move through the liver and bile ducts quickly enough, the pigment in bile (bilirubin) builds up in the blood and is deposited in the skin. As a result, the skin and the whites of the eyes turn yellow (called jaundice). The narrowing or blockage can prevent bile (which contains pigments such as bilirubin) from entering the small intestine and being eliminated in stool. As a result, the stools become pale, and because more bile is eliminated in urine, the urine becomes dark.
Itching (pruritus) is common, often beginning in the hands and feet but usually affecting the whole body. Itching is especially worse at night. Bile duct infection (cholangitis) may also occur, producing abdominal pain, chills, and fever.
The diagnosis is based on the symptoms and abnormal blood test results, especially in people who have conditions that make ischemic cholangiopathy more likely (such as liver transplant recipients).
Ultrasonography helps doctors visualize the ducts, but the results may be inconclusive. Better definition often requires magnetic resonance imaging of the bile ducts (a procedure called magnetic resonance cholangiopancreatography, or MRCP) or endoscopic retrograde cholangiopancreatography (ERCP). ERCP involves inserting a flexible viewing tube (endoscope) through the mouth and into the small intestine and injecting a contrast agent into the bile duct system.
In addition to detecting narrowing of the bile ducts, ERCP can be used to treat strictures. A wire with a deflated balloon at its end is introduced through the endoscope. Doctors inflate the balloon to widen (dilate) narrowed areas. A mesh tube (stent) is then inserted to keep the duct open.
If people have had a liver transplant, the drugs they take to prevent rejection may need to be changed, or they may require another transplant.