Primary biliary cholangitis (formerly primary biliary cirrhosis)

What is primary biliary cholangitis?

Primary biliary cholangitis (PBC) is a long-term condition in which your immune system mistakenly damages the small bile ducts inside your liver. You may know it by its older name, primary biliary cirrhosis: the name was changed in 2015, since most people with the condition never actually develop cirrhosis.

What are the symptoms of primary biliary cholangitis?

Many people have no symptoms at all when PBC is first picked up, often through a blood test done for something else entirely. When symptoms do appear, the two most common by far are:

• extreme tiredness (fatigue)
• itchy skin

Neither of these tends to reflect how far the condition has progressed, so mild itching doesn't necessarily mean mild disease. Other early symptoms can include:

• discomfort or pain below your ribs on the right-hand side
• joint or bone aches
• dry eyes and a dry mouth
• indigestion

If the condition progresses without treatment, further signs can develop, including darkened patches of skin, small yellow fatty deposits under the skin (xanthomas), unexplained weight loss, easy bruising, swollen feet or a bloated tummy from fluid build-up, and jaundice, where the skin and the whites of the eyes turn yellow.

What causes primary biliary cholangitis, and who is at risk?

PBC is an autoimmune condition: for reasons that aren't fully understood, your immune system starts attacking the lining of the small bile ducts in your liver instead of protecting you. This damages the ducts, and bile that would normally drain away starts to build up and injure the surrounding liver tissue.

Experts think a combination of genes and an environmental trigger is involved, rather than a single cause. Possible environmental triggers that have been suggested include infections, smoking and exposure to certain chemicals, though none has been proven. Your diet and how much you drink do not appear to play a meaningful part in triggering it.

PBC can affect anyone, but some groups are more commonly affected:

• women, who make up around 9 to 10 of every 10 people diagnosed
• people typically in their late thirties to fifties or sixties when diagnosed, though it can occur outside this range
• people living in parts of northern Europe, including Scotland, Scandinavia and the north-east of England, for reasons that remain unclear
• people with a close relative who has PBC, or a personal history of another autoimmune condition such as rheumatoid arthritis, scleroderma or Sjögren's syndrome

In the UK, an estimated 22,000 people are living with PBC and it's being diagnosed more often than in the past.

Are there different types of primary biliary cholangitis?

PBC doesn't have separate named subtypes, but it's easily confused with a similarly named condition, primary sclerosing cholangitis (PSC). PBC affects only the bile ducts inside your liver, tends to affect a different group of people, and can be treated with medicine, whereas PSC affects bile ducts both inside and outside the liver and currently has no effective drug treatment.

You might also come across the terms 'asymptomatic' and 'symptomatic' PBC. Around 6 in 10 people are diagnosed before any symptoms begin, usually after a routine blood test picks up early signs, while others aren't diagnosed until symptoms such as fatigue or itching have already appeared.

How is primary biliary cholangitis diagnosed?

Your doctor will ask about your symptoms, your family's medical history and whether you have any other autoimmune conditions and will examine your tummy and check for yellowing of your skin or eyes. Most people, however, are picked up through a routine blood test done for an unrelated reason.

A blood test looking for antimitochondrial antibodies (AMA) is central to diagnosis: around 95% of people with PBC test positive for these. Your blood will likely also be checked for raised alkaline phosphatase (a liver enzyme) and cholesterol, both of which tend to be higher than normal in PBC. If your AMA and alkaline phosphatase results both point to PBC, your doctor can often confirm the diagnosis without further tests.

You'll usually also have an ultrasound scan, and sometimes an MRI or X-ray, to check your liver and bile ducts and rule out other causes such as gallstones or a blockage. A liver biopsy, where a doctor takes a tiny piece of your liver to examine under a microscope, isn't always needed, but may be used if your antibody test is negative despite other signs of PBC, or to see how advanced the liver damage is.

How is primary biliary cholangitis treated?

PBC cannot currently be cured, but treatment can slow its progress and ease symptoms. Most people are managed with medicine and lifestyle changes rather than surgery.

Non-surgical treatment

Ursodeoxycholic acid (also called UDCA, ursodiol or Urso) is the first medicine offered. This bile salt helps drain bile from the liver and slows liver damage; people who respond well early on tend to avoid needing a transplant later. Sources vary on how many people respond well: the PBC Foundation puts non-response at around 20 to 30%, while other sources suggests the medicine works well for roughly half of people.

If UDCA alone isn't enough, your doctor may add obeticholic acid. This can improve blood test results, but it may also make itching worse, has not been shown to change the overall course of the disease, and isn't suitable if you already have cirrhosis. Other medicines, such as fibrates, or newer options your doctor may discuss with you, are sometimes used alongside UDCA as well.

Alongside medicine for the liver itself, your doctor may recommend treatment for individual symptoms and complications:

• for itching: medicines such as cholestyramine or rifampicin, antihistamines, or light therapy
• for fatigue: in some cases, a stimulant medicine
• for low fat-soluble vitamin levels: supplements of vitamins A, D, E and K
• for raised cholesterol: a statin
• for a higher risk of thinning bones: bone-protecting medicine plus calcium and vitamin D
• for dry eyes and mouth: regular eye and dental check-ups
• for fluid retention: a low-salt diet and, if needed, a diuretic medicine to help remove excess fluid

For itchy skin day to day, practical steps can also help. Keep nails short, choose natural fabrics such as cotton, get moderate sun exposure where possible, and avoid overheating, hot baths and strongly perfumed soaps or bath products.

A generally healthy lifestyle supports the liver too. Eating a nutritious, whole-food diet, staying at a healthy weight, taking regular weight-bearing exercise for bone health, avoiding smoking, and cutting down on (or, if you have cirrhosis, stopping) alcohol. Always check with your doctor before starting new medicines or supplements, including complementary or alternative remedies.

Surgical treatment

If the liver becomes severely scarred and medicine no longer controls the condition well enough, your doctor may consider a liver transplant, usually once other options have been ruled out. Transplant surgery generally has good outcomes for people with PBC, and life expectancy afterwards is normal, though the condition can occasionally return in the new liver, typically progressing more slowly the second time.

When should I see a doctor?

Mention the following to your doctor, particularly if you haven't been investigated for PBC before:

• ongoing tiredness or itchy skin that hasn't been explained
• yellowing of your skin or the whites of your eyes
• a close family member diagnosed with PBC, or your own history of another autoimmune condition

If you already have a PBC diagnosis, get medical advice promptly if you notice new swelling in your tummy or legs, vomit blood or pass black stools, or become unusually confused, as these can signal a complication that needs urgent attention. Otherwise, keep up with the regular checkups your doctor recommends, so your treatment can be reviewed as needed.