• Primary biliary cholangitis (PBC) is considered an autoimmune disorder.
• PBC is believed to be caused by a combination of genetic and environmental factors.
• Having risk factors for PBC increases a person’s chances of developing the disease.

Experts believe that primary biliary cholangitis (formerly known as primary biliary cirrhosis) occurs because of two main factors. First, you may be more likely to have this condition as a result of your genes. Second, PBC may develop when certain elements in your environment trigger the condition.

Together, these genetic and environmental factors lead to immune system changes that affect your bile ducts. Your liver makes bile, which is a fluid that helps with digestion. Small bile ducts (tubes) inside your liver carry this fluid out to larger bile ducts that then transport it to your gallbladder and small intestine.

PBC damages your bile ducts. When bile can’t move around as easily, it accumulates in your liver. Over time, the buildup may make it harder for your liver to do its job.

Primary Biliary Cholangitis Causes

Experts don’t fully understand what exactly causes PBC, but they’re constantly learning more through research.

Most doctors and researchers believe that PBC is an autoimmune disease, meaning the immune system attacks healthy tissues. If you have PBC, you probably have large numbers of white blood cells called T cells in your liver. T cells usually help fight infections, but in PBC, they mistakenly damage the cells that make up your bile ducts. This eventually leads to ongoing inflammation, cirrhosis (scarring of liver tissue), and possibly liver failure.

About 19 out of 20 people with PBC also have antimitochondrial antibodies (AMA), which are biomarkers (medical signs that can be measured) for autoimmune disease. Experts don’t yet understand the exact role of AMA in liver function and symptoms of PBC, like fatigue, pruritus (itching), dry eyes, and jaundice (yellowing of the skin).

Risk Factors for Primary Biliary Cholangitis

Certain factors may increase your chances of developing PBC, but they don’t guarantee you’ll get it. Some people may have risk factors without ever developing the condition, while others with no risk factors may be diagnosed with this liver disease.

In general, experts believe that PBC develops as a result of both types of factors — genetic (inherited) and environmental (lifestyle). Talk with your doctor if you’d like to learn more about your individual chances of developing this condition.

Age

Middle-aged individuals have the highest risk of being diagnosed with PBC. Some experts say the condition most often occurs between ages 30 and 60, while others say the risk is highest in people aged 45 to 65.

Inherited Risk Factors

Some PBC risk factors are present when you’re born. These inherited factors generally can’t be changed.

Sex

Women and people assigned female at birth are about 10 times more likely to develop PBC compared with men and people assigned male at birth, according to Cleveland Clinic.

Family History

Do you have a parent or sibling who’s been diagnosed with PBC? If so, you’re 100 times more likely to also develop the condition.

PBC isn’t a traditional type of genetic disease caused by a single mutation (gene change), but genetic mutations passed down within families may contribute to the condition. Experts are still learning about what these gene changes are and why they lead to PBC.

Ancestry

According to the National Institute of Diabetes and Digestive and Kidney Diseases, PBC occurs more often in white people than those of other ethnic or racial groups. In particular, you may have an increased risk if you’re from England, Scotland, Denmark, Norway, or Sweden.

Environmental Risk Factors

Certain PBC risk factors are linked to your lifestyle or surroundings. You may have more control over your exposure to these environmental factors.

Infections

Living with an infection may increase your risk of developing PBC later on. For example, there’s a strong link between PBC and urinary tract infections.

Although it’s not entirely clear why, researchers have found that some people with PBC have antibodies in their blood that target proteins found on bacteria or viruses. These antibodies, which may be left over from an infection, could mistakenly attack normal proteins that look similar to bacterial or viral proteins. This may lead to the liver inflammation seen in PBC.

To reduce your risk of PBC, it may help to protect against infections. Look out for potential symptoms of infections, such as:

• Fever or chills
• Painful or frequent urination
• Changes in vaginal discharge
• Sore throat
• Mouth sores
• A stuffy or runny nose
• Neck stiffness
• Coughing
• Difficulty taking a deep breath
• Abdominal pain
• Vomiting or diarrhea
• Swelling, heat, or redness

Some of these symptoms may occur with a mild infection, but make sure to talk to your doctor and get treatment right away for symptoms that concern you or persist.

Smoking Cigarettes

People who are exposed to cigarette smoke are more likely to develop PBC. Smoking may also speed up the progression of PBC, possibly because of toxic chemicals in cigarettes.

Exposure to Chemicals

You may be more likely to be diagnosed with PBC if you regularly come into contact with toxic chemicals. For example, your risk may increase if you work with chemicals or live near a site where toxic waste is dumped. Additionally, some studies have found links between the risk of PBC and frequent use of nail polish.

These chemicals may trigger inflammation in your body, which in turn leads to the immune system problems seen during PBC.

Determining Your Primary Biliary Cholangitis Risk

If you’re worried about developing PBC, it may help to ask your health care team about your personal risk levels. If you have PBC risk factors, such as a family history of the condition, your doctor may recommend regular visits to make sure your liver is in good health. They may also recommend that you see a gastroenterology or hepatology specialist.

Standard blood tests can indicate whether you may have a liver condition like PBC. For example, high levels of the alkaline phosphatase enzyme are often a sign of liver damage. Read more about the diagnosis of PBC here.

Talk With Others Who Understand

On myPBCteam, the social network for people and their loved ones living with primary biliary cholangitis, members come together to ask questions, give advice, and share their stories with others who understand.

Are you living with PBC? Do you have more questions about risk factors for PBC? Share your experience in the comments below, or start a conversation by posting on your Activities page.