Symptoms:
Common symptoms of PSC may include:
- Persistent and extreme fatigue
- Itching of the skin without a clear cause
- Pain or discomfort in the upper right side of the abdomen
- Diarrhea
- Fever, often linked to repeated infections of the bile ducts
- Yellowing of the skin or the whites of the eyes (jaundice), depending on skin tone
When to seek medical advice
Medical attention is recommended if there is unexplained, long-lasting itching over a large area of the body. It is also important to consult a healthcare professional if there is ongoing, severe tiredness that does not improve with rest.
People with inflammatory bowel diseases such as ulcerative colitis or Crohn’s disease should be especially alert to persistent fatigue and discuss it with their doctor, as PSC is more common in these conditions.
Causes:
PSC is considered an immune-mediated disease, meaning the immune system mistakenly attacks healthy tissues in the body, particularly the bile ducts.
Inflammation is normally a protective response to injury or infection, increasing blood flow and activating immune defenses. While this process helps healing in the short term, long-term or misdirected inflammation can cause ongoing tissue damage.
In PSC, the exact trigger of bile duct inflammation is not fully understood. Research suggests the condition does not follow simple inheritance patterns from parents to children. Instead, it likely develops from a combination of genetic susceptibility and environmental influences.
Factors that may contribute include immune system dysfunction, changes in the gut environment such as alterations in the microbiome, and exposure to certain environmental triggers. A strong link exists between PSC and inflammatory bowel disease (IBD), particularly ulcerative colitis. Around 70% to 80% of people with PSC also have IBD, while a smaller proportion have Crohn’s disease.
Risk factors
Several factors may increase the likelihood of developing PSC:
- Age: Can occur at any age but is most commonly diagnosed in middle adulthood
- Sex: More frequently seen in males than females
- Inflammatory bowel disease (IBD): About 5% to 7% of people with ulcerative colitis or Crohn’s disease also develop PSC
- Geography: Higher rates have been reported in Northern Europe and North America
- Genetics: Certain genetic variations may contribute to increased susceptibility
Complications
PSC can lead to several serious health complications, especially as the disease advances:
- Liver disease and liver failure: Ongoing inflammation can cause scarring of the liver (cirrhosis), leading to a gradual loss of liver function
- Cancer risk: Increased risk of bile duct and gallbladder cancers, along with a lower but still present risk of liver and pancreatic cancers. Those with both PSC and IBD also have a higher risk of colon and rectal cancer
- Portal hypertension: Increased pressure in the portal vein can lead to blood vessel strain in the digestive system, internal bleeding, and fluid buildup in the abdomen
- Bacterial infections: Blocked or narrowed bile ducts can become infected, especially after medical procedures
- Bone weakness: Reduced bone density or osteoporosis may occur over time
- Vitamin deficiencies: Impaired bile flow can affect absorption of vitamins A, D, E, and K, leading to deficiencies
Diagnosis:
Primary sclerosing cholangitis (PSC) is diagnosed using a combination of blood tests, imaging studies, and sometimes tissue sampling. These tests help evaluate liver function, detect bile duct damage, and rule out other conditions.
Liver function blood tests
Blood tests are used to assess how well the liver is working. They measure enzymes and proteins such as alkaline phosphatase, which is often elevated when bile ducts are inflamed or blocked.
MRI of the bile ducts
Magnetic resonance imaging (MRI), particularly magnetic resonance cholangiopancreatography (MRCP), is the main imaging test used to diagnose PSC. It provides detailed images of the liver, bile ducts, gallbladder, and pancreas, helping to identify narrowing, scarring, or blockages in the bile ducts.
X-ray imaging of the bile ducts
In some cases, a specialized X-ray test called a cholangiogram may be used if MRI is not suitable. This test uses a contrast dye to make the bile ducts visible on imaging. The dye can be introduced using an endoscopic procedure (ERCP), where a tube is passed through the digestive tract into the bile duct, or by injecting it through the skin into the liver.
Liver biopsy
A liver biopsy involves removing a small sample of liver tissue using a needle. The sample is examined under a microscope to assess inflammation, scarring, and changes in the bile ducts. This test is particularly useful when imaging results are unclear or when there is suspicion of overlapping conditions such as autoimmune hepatitis.
Colon examination
A colonoscopy is often performed to evaluate the large intestine (colon). During this procedure, a flexible tube with a camera is inserted through the rectum to examine the colon lining and collect tissue samples if needed.
If a person has not already been diagnosed with inflammatory bowel disease, a colonoscopy may be done to check for conditions such as ulcerative colitis or Crohn’s disease. It can also detect abnormal growths or early signs of colon cancer. Regular colonoscopic monitoring is commonly recommended after a diagnosis of PSC due to the increased risk of colon cancer.
Treatment:
There is currently no approved treatment that can stop or reverse the progression of PSC. Management focuses on relieving symptoms, treating complications, and monitoring liver health over time.
Ursodeoxycholic acid (Ursodiol)
Ursodiol is a naturally occurring bile acid that may improve liver test results in some patients when used in low doses. It may also help reduce itching in certain cases. However, it does not prevent disease progression or long-term complications.
Managing itching
Itching (pruritus) can be treated with several types of medications:
- Antihistamines: May help mild itching and are sometimes used at night due to their sedative effect
- Bile acid sequestrants: Medicines such as cholestyramine and colestipol bind bile acids that may contribute to itching, but they can cause constipation and interfere with vitamin absorption
- Rifampin: An antibiotic that may help reduce moderate to severe itching, though it requires monitoring due to potential liver effects
- Opioid antagonists: Medications like naltrexone may help in severe cases but are not suitable for advanced liver disease
Nutritional support
PSC can interfere with the absorption of fat-soluble vitamins, even with a balanced diet. Vitamin supplements may be recommended, either as tablets or intravenous infusions. Calcium and vitamin D may also be prescribed to support bone health if bone thinning occurs.
Treating bile duct blockages
Blockages in the bile ducts may occur due to disease progression or, in some cases, cancer. Endoscopic procedures (ERCP) can help relieve these blockages:
- Balloon dilation: A small balloon is inserted and inflated inside the narrowed bile duct to widen it
- Stent placement: A small tube is inserted to keep the bile duct open; stents may need to be replaced periodically
Treating infections
Bacterial infections of the bile ducts are common when bile flow is blocked or slowed. Treatment may include antibiotics and, in some cases, ERCP procedures to clear blockages and restore bile flow.
Liver transplant
Liver transplantation is currently the only known cure for PSC. During this procedure, the damaged liver is replaced with a healthy donor liver.
Not all individuals with PSC require a transplant. Many manage the condition for years with regular monitoring and symptom control. A transplant is usually considered when severe complications develop, such as liver failure, recurrent infections, uncontrollable symptoms, or bile duct or liver cancer that cannot be treated otherwise.
Outcomes after liver transplantation are generally very good, with high survival rates. However, PSC can sometimes return even after a successful transplant.
Prognosis
The progression of PSC varies widely between individuals. On average, life expectancy without a liver transplant ranges from about 10 to 20 years after diagnosis, although some people experience faster or slower progression.
The disease course is often unpredictable. Some individuals remain stable for long periods, while others develop complications more rapidly. Liver transplantation significantly improves long-term outcomes for those with advanced disease.