What is Primary Sclerosing Cholangitis (PSC)?
PSC is an uncommon chronic liver disease in which the bile ducts inside and outside the liver progressively decrease in size due to inflammation and scarring (fibrosis). The disease may occur alone, but frequently is associated with inflammatory diseases of the colon, especially chronic ulcerative colitis.
Bile ducts are tubes which carry bile (a greenish yellow liquid made by the liver) into the upper part of the bowel. Bile acts as a detergent breaking up fat from the food we eat into small droplets that can then be absorbed into the body. It also enables the body to absorb vitamins A, D, E and K from our diet.
As a consequence, bile that is normally carried by these ducts accumulates within the liver. This blockage to bile flow also causes damage to liver cells causing inflammation and scarring. Over many years the scarring can affect the whole liver and the system of bile ducts. A damaged liver can re-grow without scarring but in PSC, the re-growth goes wrong and the healing process is incomplete. The combination of scar tissue and irregular growth is known as cirrhosis.
Many people have no symptoms at first and the disease is only discovered because of abnormal results of routine blood tests in patients with ulcerative colitis or Crohn’s disease. In some people PSC does not produce any symptoms. Most people have few or no symptoms for many years.
Common early symptoms are:
- some abdominal discomfort in the right upper abdomen.
Late symptoms are:
- jaundice – yellowing of the skin and whites of the eyes
- episodes of fever, shaking and chills can be distressing but are uncommon.
Liver failure may ultimately develop.
PSC may be occasionally complicated by the development of bile duct cancer. PSC is closely associated with inflammatory bowel disease, usually ulcerative colitis, but also Crohn’s disease.
The course of the ulcerative colitis is often very mild, with few flare-ups. However bowel cancer does appear to develop more frequently in patients with colitis who also have PSC and regular yearly examination of the colon by colonoscopy (a tiny video camera) is recommended.
PSC is diagnosed on the combination of symptoms, blood tests and a picture of the bile ducts, called a cholangiogram. A liver biopsy may be needed not only to confirm the diagnosis, but also to assess either how early or advanced the disease is.
If your GP suspects you may have the condition you will be referred to a hospital specialist for tests, expert advice and treatment.
It is not possible to prevent PSC because the cause remains unknown. Liver damage and cirrhosis is often presumed to be caused by drinking too much alcohol, however PSC is not related to alcohol in any way.
Current evidence suggests that the disease may be triggered by an unknown bacteria or virus in people who are genetically programmed to get the disease. The common viruses known to cause hepatitis have not been associated with it.
The frequent occurrence of PSC in association with inflammatory bowel disease suggests that a common cause for both diseases may exist or that the inflamed colon allows toxins or infections to be absorbed into the body and this can cause the bile duct inflammation. The disease affects both genders, although two male patients are affected for every female patient. It can affect all ages, but it is most commonly found in young adults.
At present there is no known cure or specific treatment for PSC although preliminary trials have suggested that the natural bile acid, ursodeoxycholic acid, may slow the progression of the disease possibly by increasing bile flow and reducing liver inflammation. Symptoms such as itching can be treated with agents such as cholestyramine, rifampicin or naltrexone.
Cholestyramine (trade name Questran® or Questran Light®) may be prescribed to help relieve itching. It works better when taken before and after meals, especially breakfast, but it may take some days before the treatment is effective. Some people taking Questran® experience side effects such as altered bowel habits or bloating. If this is a problem, tell your doctor as there are other treatments such as albumin dialysis that may suit you better.
Many people suffer with a dry mouth and dry eyes, but this can be helped by taking lozenges and artificial tears prescribed by your doctor.
For a few people who eventually go on to get advanced cirrhosis, a liver transplant may be recommended when their quality of life has deteriorated and medical treatment can no longer control their symptoms. Because PSC usually develops slowly, transplantation can generally be carefully planned well ahead.
People with advanced PSC are often deficient in vitamins A, D and K and replacement fat-soluble vitamins are given. Endoscopic treatment of the bile ducts is aimed at reducing or halting the progression of the disease, usually by stretching or dilating the narrowed bile ducts. In later stages of the disease liver transplantation is often an option. Survival after this operation is good, although in some patients PSC can recur in the new liver.
Looking after yourself
When someone has a long-term liver problem such as PSC, the liver’s ability to carry out its many functions may not be as good as in a healthy person. In particular, the liver’s ability to break down alcohol and medicines may be impaired, however this is often not a problem. If in doubt, check with your doctor.
Many people with PSC can eat a normal diet, while others may need more detailed advice. If you are well with few symptoms you may not need to make any changes, although it is important to eat as healthily as possible. vA few people have problems digesting fat and can develop a type of diarrhoea called steatorrhoea, in which stools are bulky, pale and difficult to flush away. There may also be nausea. If this occurs, it may help to reduce the amount of fat in the diet but only under the supervision of a dietician. Some people may need energy supplements and injections of fat-soluble vitamins. Others are prescribed medium chain triglycerides (MCT) which are fats that are easier to digest.
It is important to talk to your doctor or dietician before making any changes in your diet.
Tiredness is the commonest symptom of PSC. Some people may need to consider making changes to their lifestyle and pacing their daily activities helps to preserve stamina and energy. Gentle exercise such as walking and swimming can be beneficial.
Do tell your dentist that you have PSC as there may be an increased risk of bleeding.
It is Important that you talk to your doctor before taking any medicine (not prescribed by him or her), including paracetamol, herbal remedies and Chinese medicine.
If you are female and middle aged, it is important to discuss with your doctor the best way of reducing your risk of developing osteoporosis.Your doctor may advise various measures which might include increasing the intake of calcium in your diet, taking calcium supplements and HRT (hormone replacement therapy) if appropriate.
UK-PSC is a collaborative venture between NHS Trusts across the UK, researchers and patient groups aimed at improving our understanding of PSC and the way it impacts on the lives of patients. People of all ages (including children) with PSC are encouraged to join. Visit www.uk-psc.com
Please visit the support section of our website for information on Support groups in your area or visit our Useful Links section for other organisations who may be able to offer information and support.
Reviewed by: Dr Roger Chapman BSc (Lon) MD (Lon) MBBS FRCP, John Radcliffe Hospital, Oxford.
The Trust has been donated the use of this video discussing the physiology of Primary Sclerosing Cholangitis – it is aimed at medical students but after asking for feedback, some patients have also said they find it useful. It can be quite technical, so please discuss any content that you are unsure about with your medical team.