Primary Biliary Cholangitis
Primary biliary cholangitis (PBC) is a chronic liver disease characterized by inflammation and progressive destruction of bile ducts. Bile is a substance produced in the liver that helps digest fat in the small intestine and remove toxins from the body. When the ducts are damaged, bile backs up into the liver, damaging liver tissue. Prolonged inflammation of the liver can result in irreversible scar tissue, which leads to cirrhosis.
Cause
The cause of PBC is unknown, but it is thought to be an autoimmune disease. An autoimmune disease occurs when the body’s immune system fails to recognize its own tissues and attacks them. In PBC, it is thought that the immune system attacks and destroys the small bile duct cells in the liver.
Symptoms
PBC affects mostly women (about 90-95%) and usually occurs between the ages of 30 and 60 years. Many patients may not have any symptoms or complaints for years. Signs and symptoms may include diffuse, and often intense, itchiness (pruritus) and fatigue.
Other symptoms may eventually develop, including:
- Jaundice (yellowing of the eyes and skin)
- Hypercholesterolemia (elevated cholesterol levels)
- Fatty deposits under the skin
- Fluid retention
- Dry eyes and mouth (sicca syndrome)
In the later stages of the disease, some people develop osteoporosis, arthritis, and thyroid problems.
Diagnosis
Patients are screened with blood tests, which can show abnormal liver tests with elevated alkaline phosphatase (ALP). Occasionally, other abnormal liver tests may show elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Bilirubin levels are usually normal until later stages of the disease. Additional laboratory tests include anti-mitochondrial antibody (AMA), which is used to confirm the diagnosis, as up to 95% of those with PBC test positive. Your doctor may also order other tests, such as an ultrasound and liver biopsy, to help determine the extent of disease progression. A liver biopsy uses a thin needle to remove a small sample of liver tissue. The sample is then examined with a microscope. However, a liver biopsy is not always necessary to make the diagnosis, especially if the AMA is positive.
Treatments
Initial treatment aims to relieve symptoms. In those who experience intense itchiness or pruritus, symptoms can be managed with an antihistamine such as diphenhydramine and bile acid binders such as cholestyramine and colestipol. PBC can be associated with deficiencies in fat–soluble vitamins, as well as bone thinning (osteoporosis). Vitamin levels should be monitored and replaced accordingly. Those with osteoporosis should be treated with calcium and vitamin D, along with exercise.
Some patients have also benefited from ursodeoxycholic acid (also known as ursodiol and marketed under the names Actigall and Urso Forte). Ursodiol enhances bile flow and is the only drug approved by the U.S. Food and Drug Administration for the treatment of PBC. Ursodiol does not cure the disease, but it can help delay its progression. If the liver becomes severely damaged, a transplant may be necessary.
Resources
For more information about this disease, check out the following sites: