Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is a disease caused by damage to bile ducts in the liver. These small channels carry the digestive fluid, or bile, from the liver to the small intestine. In the intestine, bile helps break down fat and aids in the absorption of fat-soluble vitamins, such as A, D, E, and K.

Damage to the bile ducts allows bile to build up in the liver. Over time, the accumulated bile damages the liver. It can lead to permanent scarring and cirrhosis.

People with PBC may not develop any symptoms for up to 10 years. Once symptoms start, the average life expectancy is about 10 years. However, everyone is different. Some people live longer than others with the disease. New treatments are improving the outlook for people with PBC.

PBC has four stages. They’re based on how much damage has been done to the liver.

  • Stage 1. There’s inflammation and damage to the walls of medium-sized bile ducts.
  • Stage 2. There’s blockage of the small bile ducts.
  • Stage 3. This stage marks the beginning of scarring.
  • Stage 4. Cirrhosis has developed. This is permanent, severe scarring and damage to the liver.

PBC develops slowly. You may not have any symptoms for years — even after you’ve received a diagnosis.

The first symptoms are often fatigue, dry mouth, and dry eyes along with itchy skin.

Later symptoms can include:

  • belly pain
  • darkening of the skin
  • nausea
  • appetite loss
  • weight loss
  • dry eyes and mouth
  • small yellow or white bumps under the skin (xanthomas) or eyes (xanthelasmas)
  • joint, muscle, or bone pain
  • yellowing of the skin and eyes (jaundice)
  • swollen belly from fluid buildup
  • swelling in the legs and ankles (edema)
  • diarrhea
  • fractures caused by weakened bones

PBC can cause progressive liver damage. Bile and the substances it helps to remove from your body can become trapped in your liver. The backup of bile can also affect nearby organs like your spleen and gallbladder.

When bile gets stuck in your liver, less of it is available for digestion. A lack of bile can prevent your body from absorbing enough nutrients from foods.

Possible complications of PBC include:

PBC is an autoimmune disease. This means your immune system mistakes tissue in your liver for a foreign invader and attacks it.

Your immune system has an army of “killer” T cells that identify and fight off harmful invaders like bacteria and viruses. In people with PBC, these T cells mistakenly attack the liver and damage cells in the bile ducts.

Doctors don’t know exactly what causes this immune system attack. It’s likely triggered by both genetic and environmental causes.

You’re more likely to develop PBC if you’re female. About 90 percent of people diagnosed with PBC are female, according to the American Liver Foundation.

Additional risk factors include:

  • being between the ages of 30 and 60
  • having a parent or sibling with this condition
  • smoking cigarettes
  • being exposed to certain chemicals

Although there’s no cure for PBC, treatments can improve your symptoms and protect your liver from further damage.

The first treatment doctors usually try is ursodeoxycholic acid (UDCA) or ursodiol (Actigall, Urso). Ursodiol is a bile acid that helps move bile from the liver into the small intestine. It can help slow liver damage, especially if you start taking it when the disease is still in the early stages. You’ll need to keep taking this drug for life. Side effects of ursodiol include weight gain, diarrhea, and hair loss.

Obeticholic acid (Ocaliva) is a newer drug that’s been approved for use in people who either can’t tolerate UDCA or who don’t respond to it. This drug lowers the amount of bile in the liver by reducing bile production and helping push bile out of the liver.

Your doctor can also prescribe medications to treat symptoms, such as:

  • For itching: antihistamines like diphenhydramine (Benadryl), hydroxyzine (Vistaril), or cholestyramine (Questran)
  • For dry eyes: artificial tears
  • For dry mouth: saliva substitutes

You’ll also need to avoid alcohol since it can further damage your liver.

If you become deficient in fat-soluble vitamins, you can take supplements to replace them. Taking calcium and vitamin D can help keep your bones strong.

Some doctors prescribe immune-suppressing drugs to prevent the immune system from attacking the liver. These drugs include methotrexate (Rheumatrex, Trexall) and colchicine (Colcrys). However, they haven’t been proven effective for PBC specifically.

The American Liver Foundation states that ursodiol works in about 50 percent of the people who take it. For the rest, liver damage may continue.

If your liver becomes too damaged to work properly, you’ll need a liver transplant. This surgery replaces your liver with a healthy one from a donor.

Because PBC causes no symptoms in its early stages, it may be diagnosed during a routine blood test your doctor orders for another reason.

Your primary care doctor or a liver specialist called a hepatologist can diagnose PBC. The doctor will first ask about your symptoms, health history, and family medical history. You’ll also have a physical exam.

Tests used to diagnose this condition include:

Your doctor may also perform imaging tests to make a diagnosis. These include:

PBC is chronic and progressive. It’s not curable, and over time it can lead to permanent liver damage.

However, PBC usually develops slowly. That means you may be able to live normally for many years without any symptoms. And once you do develop symptoms, medication can help manage them. Better treatments have improved the outlook for people with PBC in recent years.

To have the best possible outlook, follow the treatment your doctor prescribes. Stay healthy with diet, exercise, and by not smoking or drinking alcohol.