IBD and Primary Sclerosing Cholangitis (PSC)

Primary sclerosing cholangitis (PSC) is a disease of the liver that causes inflammation and narrowing of the bile ducts inside and outside of the liver. It's not certain what causes PSC, although it is thought to be an autoimmune condition. PSC is not thought to be directly inherited, but it is thought to have a genetic component.

Bile is necessary for the digestion of fat and to carry waste out of the liver. PSC causes the bile ducts to narrow from scarring and inflammation, and bile begins to accumulate in the liver, which damages it. This damage eventually leads to scar formation and cirrhosis, which prevents the liver from performing its important functions. Several years of PSC can lead to a cancerous tumor of the bile ducts called cholangiocarcinoma, which occurs in 10 to 15% of patients.

PSC does progress slowly in most cases, but it can also be unpredictable and life-threatening. People with PSC can receive treatment to relieve symptoms and help them lead an active life. 

At-Risk Demographic

Most often, the people who are affected by PSC are between the ages of 30 and 60, with the average age of diagnosis being 40. PSC tends to be more common in men; 60 to 75% of people diagnosed are men. On the whole, PSC is an uncommon disease.

Symptoms

Some people have no symptoms at diagnosis or even for several years after.

Symptoms include:

• Diarrhea (caused by malabsorption of fat)
• Fatigue
• Fever/chills (from an infection in the bile ducts)
• Itching which often affects the entire body
• Jaundice (yellowing of the skin and eyes)

Associated Diseases

People with PSC are more likely to have inflammatory bowel disease (IBD) or osteoporosis. PSC is strongly associated with ulcerative colitis in up to 70 percent of patients, but it can also be associated with Crohn's disease of the large intestine, sometimes called Crohn's colitis. The reason for the association with IBD is unknown, but it is thought to be the result of an immune response.

Diagnosis

PSC was traditionally diagnsoed with a procedure called endoscopic retrograde cholangiopancreatography (ERCP). During an ERCP, the physician inserts an endoscope into the mouth and navigates it down through the esophagus and stomach to the ducts of the biliary tree. Dye is inserted into the ducts so that they will show up when x-rays are taken. The x-rays are then analyzed to determine if there are any problems with the bile ducts.

However, ERCP is invasive and especially in the setting of PSC can lead to very serious complications such as pancreatitis and bacterial cholangitis, which in turn can lead to sepsis and death.

Instead, the first step per guidelines is obtaining alkaline phosphatase levels (ALP) in patients who appear to have the signs and symptoms of PSC; however, a negative ALP does not exclude PSC. The second step involves obtaining an imaging study called MRCP, magnetic resonance cholangiopancreatography (MRCP). Sensitivity and specificity of MRCP is 80% and 87%, respectively, for the diagnosis of PSC. However, it should be noted that that patients with early changes of PSC may be missed by MRCP, and ERCP still has a useful role in excluding large duct PSC where MRCP views may not be optimal.

A liver biopsy can be useful when the imaging modalities are not diagnostic or when overlap syndrome is suspected. This procedure is done in a hospital setting on an outpatient basis with a local anesthetic. The physician performing the test will use a needle to take a small sample of liver tissue for testing by a pathologist.

Treatments

There is no treatment that has been proven to be effective for treating PSC. Research to find an effective medical treatment is currently underway. Treatment plans focus on alleviating symptoms, interrupting the progression of the disease, and monitoring for potential complications.

The symptoms of PSC can be treated to make patients more comfortable. Itching may be treated with Questran (cholestyramine) or Benadryl (diphenhydramine). For recurrent infections that may occur with PSC, antibiotics could be necessary. Because PSC interferes with the absorption of fat, supplements may be necessary to treat deficiencies of the fat-soluble vitamins A, D, E, and K. If blockages occur in the bile ducts, a surgical procedure may be necessary to stretch or open them. Stents, which keep the ducts open, may be placed in the ducts during this procedure.

If the progression of the PSC leads to liver failure or persistent biliary infections, a liver transplant may be necessary. Liver transplants offer a good quality of life for recipients, as well as a survival rate of about 75 percent.

When to Call a Doctor

If any of the following symptoms occur with PSC, call your doctor:

• Abdominal pain
• Black or very dark stools
• Jaundice
• Temperature over 100.4
• Vomiting with blood