Primary biliary cirrhosis (PBC) is a type of chronic (long-term) liver disease that is poorly understood. It can cause:
PBC gradually damages the bile ducts, and the flow of bile eventually becomes restricted. This leads to a build-up of bile in the liver, which damages the liver.
Bile and bile ducts
Bile is a yellowish-green liquid produced inside the liver that is used by the digestive system to help digest fats. It is transported out of the liver into the small bowel through a series of small tubes called bile ducts.
In PBC, for reasons that are not fully understood, the immune system (the body’s natural defence against infection and illness) gradually damages the bile ducts. Eventually, the damage leads to a blockage that obstructs the flow of bile. The amount of bile in the liver builds up to a dangerous level, causing scarring of the liver.
How common is PBC?
PBC is a rare liver condition. In England, there are an estimated 24 cases of PBC per 100,000 people. However, the rates of PBC in England are higher than in some other parts of the world. The reason for this is unknown.
PBC mainly affects women (about 90% of all cases). The condition usually occurs in people aged 30-65, and it is normally diagnosed after a person has reached 40.
The exact causes of PBC, and why it mainly affects women, are unknown. See PBC - Causes for more information.
Outlook
PBC is a progressive condition, which means that the associated damage to the liver can steadily get worse over time. The rate at which PBC progresses varies between individuals. It can take decades in many cases. If it is not treated, the liver can become damaged to such an extent that it no longer works. This is known as liver failure and can be fatal.
There is no cure for PBC but there are medicines that can help to relieve the symptoms and slow the progression of the condition. In cases where there is extensive liver damage, a liver transplant may be required.
However, over the last 20 years, the need for liver transplants as a result of PBC has been decreasing. This may be due to the use of a medicine called ursodeoxycholic acid (UDCA). See PBC - Treatment for more information.
