What is Primary Sclerosing Cholangitis (PSC)?
In primary sclerosing cholangitis (PSC), the bile ducts (a type of passage) inside and outside the liver narrow. This is due to inflammation and scarring. As the scarring increases, the ducts become narrowed or blocked. The ducts are vital because they carry bile out of the liver.
Bile is a liquid that removes toxins from the body and helps break down fat in food. If the ducts are narrowed or blocked, toxins in bile stay in the liver and damage liver cells. Also, fat and vitamins A, D, E and K may not be well absorbed. Over time, PSC can cause liver failure.
Around one out of every 100,000 people in the world are diagnosed with PSC.
Current research suggests the cause of PSC is immune mediated. When the immune system is working as it should, it protects the body from infections caused by bacteria and viruses.
In the case of immune mediated disease, the body’s immune system causes an inflammatory response against itself. In the case of PSC, the inflammation restricts or blocks bile ducts.
In many cases, PSC occurs along with a type of inflammatory bowel disease, ulcerative colitis (UC). UC causes the colon to become inflamed and develop ulcers. PCS can also occur with autoimmune hepatitis or Chrohn’s disease.
Signs and Symptoms
Since PSC progresses slowly. A person can have the disease for years before they have symptoms. Symptoms are caused by two things:
- The bile is not draining like it should through the bile ducts.
- The liver is damaged and not able to carry out its normal functions.
The symptoms of liver disease and bile duct damage are:
- Itching (may occur when toxins in bile get into the bloodstream)
- Fatigue (feeling tired all the time)
- Jaundice (yellow color in the eyes or skin − the color change is due to bile that gets in the blood and then in the skin and eyes)
- Fever, chills and soreness in the upper part of the stomach (caused by infected bile ducts)
As the disease progresses, chronic fatigue, loss of appetite, weight loss and continued jaundice may occur. In the advanced stages, swelling can occur in the stomach and feet. Liver failure may take many years to develop.
Since people with PSC may not notice symptoms for many years, the disease often is suspected due to abnormal blood tests (taken for other reasons). These blood tests show a high level of liver enzymes (which indicate abnormal liver function). The disease also might be suspected due to a history of inflammatory bowel disease.
X-ray tests can show if bile ducts are blocked, but they may not be able to determine the cause or site of the possible obstruction.
Sclerosing cholangitis is diagnosed by blood tests, along with radiologic imaging. Cholangiography is “taking a picture of the bile ducts.” The first choice for imaging includes injecting dye into the bile ducts and taking a magnetic resonance cholangiography (MRCP). The test can find the cause and site of the blockage. Many times a liver biopsy is also needed to confirm diagnosis and figure out how the disease has progressed.
Other tests that can be used to help with the diagnosis are:
- Endoscopic retrograde cholangiography (ERCP). Dye is injected into a lighted and flexible endoscope (tool used to look at the inside of some body parts). It is inserted through the mouth, stomach and then into the small intestine. A thin tube is placed through the scope and into the pancreatic and bile ducts. The dye is used to show the bile ducts on the X-ray.
- Percutaneous transhepatic cholangiography. A dilated (enlarged) bile duct is found with an ultrasound. A needle punctures the skin and places dye directly into the bile duct. X-rays are taken to find blockage.
All of these tests are done with the child sedated (given a medicine that has a soothing and calming effect) or with anesthesia (medicine given to put the child in a deep sleep with support to breathing available).
There is no cure for primary sclerosing cholangitis. Treatment is done to manage symptoms and open narrowed bile ducts. Symptoms of this disease can sometimes be managed by:
- Antibiotics to treat bile ducts that have become infected
- Diets low in salt and medicine to treat swelling of the stomach and feet caused by fluid retention
- Vitamin supplements since people with PSC often do not have enough vitamins A, D and K
- Medicine (such as Cholestyramine and Ursodiol) to control itching caused by too much bile in the bloodstream, and to improve bile flow
Endoscopic or surgical procedures may be used to open major blockages in bile ducts. A catheter is a thin, flexible tube used to drain bile from the ducts and relieve the obstruction. (See ERCP above in “Diagnosis.”)
A prosthesis (artificial device in the form of a hollow tube) may be placed in the bile ducts after they have been opened. This is to keep the ducts open. Some patients may have surgery in order to explore the bile ducts and open major blockages.
A liver transplant may be discussed as a treatment option if the liver begins to fail. The child would be checked to see if they are a candidate for a liver transplant.
If a transplant is the best treatment option, the care team will focus on preventing complications and treating symptoms while waiting for an organ.
Sclerosing cholangitis is a disease that continues to advance. It tends to become more severe over time.
Medicine does not have a major impact on slowing the progression of PSC, but it has a vital role in treating complications. For instance, Ursodiol can help stop itching, but it does not help a patient survive longer. It also does not delay the time to referral for liver transplant.
Children with PSC make up about two percent of all liver transplants done in children. Liver transplants are a success in 90 percent of these patients, who go on to have a good quality of life after they recover.