Primary Sclerosing Cholangitis
PSC, Sclerosing cholangitis
Primary sclerosing cholangitis is a rare liver disease where inflammation causes scarring and narrowing of the bile ducts, eventually leading to serious liver damage. While many people show no symptoms at first, the disease progresses slowly over 10 to 15 years and can result in liver failure and increased cancer risk.
Table of contents
- What is Primary Sclerosing Cholangitis?
- How Common is PSC?
- What Causes PSC?
- Signs and Symptoms
- Stages of PSC
- How PSC is Diagnosed
- Treatment and Management
- Complications and Related Conditions
- Outlook and Life Expectancy
What is Primary Sclerosing Cholangitis?
Primary sclerosing cholangitis is a chronic disease that affects the bile ducts, which are tubes that carry bile from your liver to your gallbladder and small intestine. Bile is an important digestive juice made in your liver that helps break down fats and absorb certain vitamins.[1]
In PSC, the bile ducts both inside and outside the liver become inflamed and scarred. This scarring causes the ducts to narrow over time. When bile ducts narrow, bile cannot flow properly and backs up into the liver, causing damage to liver cells.[2]
Over time, this damage leads to cirrhosis, which is severe scarring of the liver, and eventually liver failure. PSC is a progressive disease, meaning it gets worse over time. Currently, a liver transplant is the only cure for advanced PSC.[1]
- Liver
- Bile ducts
- Gallbladder
- Small intestine
How Common is PSC?
PSC is a rare disease. Researchers estimate that about 5 to 16 people out of every 100,000 have this condition. Some studies suggest it affects up to 1 in 10,000 people.[3][1]
The disease is more commonly diagnosed in certain groups of people. PSC affects men twice as often as women. Most people are diagnosed between the ages of 30 and 40, although the disease can occur at any age.[3][4]
People of Northern European ancestry are affected more often than those of Southern European or Asian descent. The disease is virtually always seen in nonsmokers. While PSC remains uncommon, there has been an increase in diagnosed cases over time, though this may be partly because better medical imaging has made it easier to detect.[4]
What Causes PSC?
The exact cause of primary sclerosing cholangitis is not known. Medical experts believe PSC is an autoimmune disease, which means the immune system mistakenly attacks normal, healthy bile duct cells instead of protecting the body from germs and disease.[3]
Several factors appear to play a role in causing PSC. These include genetic susceptibility, meaning having certain genes can increase your risk. Having a family member with PSC increases your chances of developing the disease. Changes to the bacteria in your gut microbiome, which is the collection of bacteria living in your digestive system, may also contribute.[2]
Environmental factors, such as exposure to certain bacteria, viruses, or toxins, might trigger an immune response in some people who are genetically predisposed to the disease. However, researchers still do not fully understand what causes the immune system to malfunction in this way.[9]
It is important to note that PSC is not caused by drinking alcohol or by anything a person did or did not do. The disease develops due to a combination of factors beyond anyone’s control.[2]
Risk Factors
Certain factors increase the likelihood of developing PSC. Being male is a risk factor, as men are twice as likely as women to have PSC. Age also matters, with most diagnoses occurring in people between 30 and 60 years old.[2]
The strongest risk factor is having inflammatory bowel disease, especially ulcerative colitis. About 70 to 80 percent of people with PSC also have inflammatory bowel disease. However, only about 3 to 7.5 percent of people with ulcerative colitis develop PSC.[3][4]
Signs and Symptoms
Many people with PSC have no symptoms when they are first diagnosed. Up to 50 percent of patients may feel perfectly fine, and the disease is often discovered accidentally during routine blood tests that show abnormal liver function.[2][4]
When symptoms do appear, they often develop slowly and may come and go. The first symptoms are usually vague and can include extreme tiredness that does not go away with rest, discomfort or pain in the upper right side of the abdomen where the liver is located, and severe itching of the skin without any visible rash.[1][2]
As PSC progresses and bile builds up in the liver, additional symptoms can develop. These include jaundice, which is yellowing of the skin and the whites of the eyes. Some people experience fever and chills, especially if an infection develops in the bile ducts. Unintended weight loss, dark-colored urine, and pale-colored stools may also occur.[2]
In more advanced stages of the disease, symptoms can become more serious. A swollen abdomen, an enlarged liver or spleen, vomiting blood, or having black-colored stools are signs that the disease has progressed significantly and requires immediate medical attention.[2]
Stages of PSC
Doctors categorize PSC into four stages based on how much scar tissue, or fibrosis, has formed in the liver. Understanding these stages helps doctors track how the disease is progressing.[2]
Stage 1 involves very little scarring in the corners of the liver, called the portal areas. In Stage 2, the scarring extends from these portal areas but does not yet connect to each other. Stage 3 is when areas of scarring begin to connect to each other. Finally, Stage 4 is characterized by connected and widespread scarring throughout the liver, leading to cirrhosis, which is permanent and severe scarring.[2]
How PSC is Diagnosed
Diagnosing PSC typically begins with blood tests. Liver function blood tests check the levels of certain proteins and enzymes, particularly alkaline phosphatase, which are often elevated when there is liver or bile duct damage. These elevated levels can be the first sign that something is wrong.[10]
The main test used to confirm PSC is magnetic resonance cholangiopancreatography, or MRCP. This is a special type of MRI scan that creates detailed images of the liver, bile ducts, gallbladder, and pancreas. The test can show the characteristic narrowing and scarring of the bile ducts that occurs in PSC.[10]
Another imaging option is endoscopic retrograde cholangiopancreatography, or ERCP. During this procedure, a doctor inserts a long, thin tube with a tiny camera through the mouth and down into the small intestine. A contrast dye is then injected into the bile ducts, and X-ray pictures are taken. This test can both diagnose PSC and, if needed, open up blocked bile ducts during the same procedure.[10]
In some cases, a liver biopsy may be performed. This involves removing a small sample of liver tissue using a thin needle inserted through the skin. The tissue is then examined under a microscope to look for signs of damage and scarring.[8]
Treatment and Management
Currently, there is no cure for primary sclerosing cholangitis, and no medical treatments have been proven to slow or stop the progression of the disease. However, doctors can treat symptoms and complications to help patients feel better and maintain quality of life.[11]
Managing Symptoms
Itchy skin is one of the most bothersome symptoms of PSC. Doctors may recommend or prescribe medicines to help relieve itching, such as bile acid sequestrants that bind to bile acids in the body, rifampin (an antibiotic that can help with itching), antihistamines for severe itching that interferes with sleep, or medications that work at the brain level to reduce liver-related itching.[11]
Because PSC can make it difficult for the body to absorb certain vitamins, especially fat-soluble vitamins like A, D, E, and K, doctors often recommend vitamin supplements and a nutrient-rich diet. Vitamin D is particularly important because it helps with calcium absorption and bone health. Without enough vitamin D, people with PSC can develop thinning bones or osteoporosis.[9][11]
Opening Blocked Bile Ducts
If bile ducts become severely narrowed or blocked, doctors may use procedures to open them. During an ERCP procedure, doctors can place small tubes called stents in narrowed ducts to hold them open for a short time. This helps bile flow more easily and can relieve symptoms.[11]
Another option is percutaneous transhepatic cholangiography, where doctors use a long needle inserted through the skin to inject dye and take X-ray pictures, and if needed, open narrowed bile ducts.[11]
Liver Transplant
For people with advanced PSC who develop liver failure, a liver transplant is the only definitive treatment and the only potential cure. During a transplant, the damaged liver is removed and replaced with a healthy liver from a donor. However, it is important to know that PSC can come back in the new liver in 25 to 30 percent of cases.[4][1]
Complications and Related Conditions
PSC can lead to serious complications over time. One major concern is liver damage that progresses to cirrhosis and eventually liver failure. When the liver fails, a transplant becomes necessary because people cannot live without a functioning liver.[2]
PSC also causes portal hypertension, which is high blood pressure in the blood vessels that drain into the liver. This can lead to additional problems such as swelling in the legs, ankles, or feet; buildup of fluid in the abdomen called ascites; and enlarged veins in the esophagus, stomach, or intestines that can burst and cause dangerous bleeding.[3]
People with PSC have an increased risk of infections in the bile ducts, called bacterial cholangitis. These infections can cause fever, chills, and abdominal pain, and they require prompt treatment with antibiotics. To help prevent infections, doctors may prescribe antibiotics before and after procedures like ERCP.[11]
Cancer Risk
One of the most serious concerns with PSC is the significantly increased risk of several types of cancer. People with PSC have a much higher risk of developing cholangiocarcinoma, which is cancer of the bile ducts. They also face increased risk of liver cancer, gallbladder cancer, and colon cancer.[1][4]
For this reason, regular cancer screening is very important for people with PSC. Doctors may suggest blood tests and imaging tests to check for bile duct and gallbladder cancer. For people with cirrhosis, blood tests and ultrasound or other imaging may be used to check for liver cancer. For those who also have inflammatory bowel disease, regular colonoscopy exams are recommended to screen for colorectal cancer.[11]
Related Conditions
Many people with PSC have other health conditions. About 70 to 80 percent of people with PSC also have inflammatory bowel disease, most commonly ulcerative colitis. Having PSC with inflammatory bowel disease may be different from having ulcerative colitis alone, and some people experience milder intestinal symptoms.[3]
People with PSC are also prone to developing other autoimmune diseases. These include type 1 diabetes, celiac disease, thyroid disease, autoimmune hepatitis, and autoimmune pancreatitis. It is unclear why PSC is linked to these other autoimmune conditions, but it supports the theory that PSC itself is an immune-mediated disease.[2][9]
Outlook and Life Expectancy
PSC is a progressive disease, which means it gets worse over time. The rate of progression varies from person to person. Some people may have the disease for many years with minimal symptoms, while others may progress more quickly.[4]
Within 10 to 15 years after diagnosis, PSC can lead to liver failure. After a person is diagnosed, life expectancy typically averages between 10 and 20 years, though this can be longer for individuals who receive a liver transplant.[2][19]
Lifestyle choices can have a positive impact on managing PSC and maintaining quality of life. Medical professionals recommend that people with PSC avoid alcohol completely, get plenty of sleep, manage stress levels, and maintain good exercise habits. Eating a healthy, nutrient-rich diet is also important.[19]
Regular monitoring by healthcare providers is essential. This includes routine blood tests to check liver function, periodic imaging studies to monitor the bile ducts and liver, and screening for cancer. Working closely with a medical team that understands PSC helps ensure that complications are caught early and managed appropriately.[11]
While PSC is a serious and chronic condition with no current cure beyond liver transplant, ongoing research continues to search for new treatments. People with PSC and their families can find support through patient advocacy groups and online communities that provide information, resources, and connections with others facing the same challenges.[6]
