The liver is the body’s factory. Aside from filtering waste out of the bloodstream, the liver aids digestion by producing a fluid called bile. This fluid flows out of the liver through the bile ducts and into the gallbladder, where it’s stored until the small intestine needs it for digestion. PBC is a chronic (long-term) inflammation of the liver’s bile ducts that ultimately destroys the ducts. Without the ducts, bile remains in the liver, damaging cells and leading to irreversible tissue scarring, known as cirrhosis. Over time, as the scar tissue builds, the liver may begin to lose function and fail.
How Common Is Primary Biliary Cholangitis?
Primary biliary cholangitis is considered a rare disease, although it’s unclear how rare it actually is. The prevalence of PBC appears to vary considerably by geographic region, ranging from 21.7 to 39.2 per 100,000 people from 2006 to 20014. (1) Among regions of the world that researchers have studied, Australia appears to have the lowest rate of PBC, while the United Kingdom, Scandinavia, Canada, and the United States have the highest rates. The disease predominantly affects women, with some estimates suggesting that about 90 percent of PBC cases occur in women. It is usually diagnosed in women between ages 30 and 60. (2)
Causes and Risk Factors of PBC
It’s unknown exactly what causes primary biliary cholangitis, but research suggests that it’s an autoimmune disease in which the immune system erroneously attacks healthy tissue (the liver’s small bile ducts, in this case). Possible risk factors for PBC include the following:
Family history of the diseaseHistory of urinary tract infections (3)Living in high latitudes (4)One or more other autoimmune diseasesHistory of smokingExposure to toxic chemicals
It’s important to note that, with the exception of a family history of PBC, many of these are relatively common risks, and not necessarily direct indicators of PBC on their own.
PBC Symptoms and Complications
The effects of primary biliary cholangitis vary greatly from person to person. Some people experience no symptoms until the later stages of the disease, while others experience early symptoms that progress quickly. The most common symptom of PBC is fatigue, affecting 80 percent of people with the disease. (5) Other signs include these symptoms:
Severe itching (pruritus)Dry skinPatches of darkened skin (hyperpigmentation)Jaundice (yellowing of the skin and eyes)Dry eyes and mouthHigh cholesterolFatty deposits under the skin caused by high cholesterolAbdominal pain
Over time, PBC may result in numerous serious complications. One such complication is increased blood pressure in the portal vein, the vein that carries blood to the liver from the stomach, intestines, spleen, gallbladder, and pancreas. This can lead to an enlarged spleen and blood vessels, fluid buildup in the extremities or abdomen, infection, iron deficiency, complications with kidney function, and cognitive issues like confusion. (6) There are other complications as well:
Poor sleep quality (7)Osteoporosis and other metabolic bone diseasesDeficiency of fat-soluble vitamins A, D, E, and KIron-deficiency anemiaLiver cancerSteatorrhea (the inability of the body to absorb fat, leading to loose, greasy, foul-smelling stool)Kidney failureBrain damage
How Is Primary Biliary Cholangitis Diagnosed?
Your doctor may suspect that you have PBC based on various factors:
Your medical and family historyA physical examinationBlood test of alkaline phosphatase during a routine check-upImaging tests of your bile ducts, including ultrasounds, magnetic resonance imaging (MRI) scans, and X-rays
A diagnosis of PBC generally requires blood tests and may include a liver biopsy, in which tissue from the liver is examined under a microscope. You may be diagnosed with the disease if you have at least two of the following:
Elevated levels of the enzyme alkaline phosphatase in your bloodA high level of antimitochondrial antibodies (AMAs) (produced by the immune system to attack mitochondria, the powerhouses of cells) in the bloodA liver biopsy showing signs of PBC
About 90 percent of people with PBC test positive for AMAs, according to a study. (8)
How Is Primary Biliary Cholangitis Treated?
There is no cure for PBC, and treatment involves managing symptoms and slowing the disease’s progression. Patients should minimize or stop alcohol consumption and also make sure they are vaccinated against hepatitis A to slow the progression of PBC. Furthermore, the drug ursodiol (Actigall) can slow the progression of liver damage in some people, possibly by reducing the amount of bile acids the liver produces. Another option for people with PBC is the drug obeticholic acid (Ocaliva), which may be used alone or in addition to ursodiol. Obeticholic acid lowers the level of alkaline phosphatase in the blood but hasn’t yet been shown to improve symptoms or slow disease progression. For symptom management, taking cholestyramine (Questran, Prevalite) can help reduce pruritus. People who experience liver failure will need a liver transplant. However, primary biliary cholangitis can recur after a liver transplant. Additional reporting by Ingrid Strauch.
