Gilbert’s syndrome is a condition where the liver does not process bilirubin very well. It is sometimes called Gilbert’s disease although it does not cause ‘disease’ as such. The liver itself is normal and the condition is usually harmless. The condition is named after the doctor who first described it in 1901.
When functioning properly, the liver filters impurities and toxins from the body, processes proteins and carbohydrates, and breaks down fats using bile stored in the gall bladder.
In a person with Gilbert’s syndrome, the liver is unable to consistently process the yellowish–brown pigment in bile, called bilirubin.
This leads to high levels of bilirubin in the bloodstream, which can cause the skin and eyes to turn yellow (jaundice). Despite the person’s jaundiced appearance, the functioning of their liver is normal.
Gilbert’s syndrome is a common, mild disorder thought to be inherited in around half of all cases. Men are at higher risk than women, and tend to develop Gilbert’s syndrome between their late teens and early 30s. Usually, the disorder is diagnosed by chance during the investigation of unrelated illnesses.
Gilbert’s syndrome is considered a harmless condition and typically does not need treatment.
Symptoms of Gilbert’s syndrome
Gilbert’s syndrome typically has no obvious symptoms, other than yellowing of the skin or eyes (jaundice). Other symptoms are sometimes reported, including gastrointestinal complaints, fatigue, weakness or abdominal pain.
However, it is not clear that these symptoms are directly related to higher levels of bilirubin.
Gilbert’s syndrome is not related to viral hepatitis, which also causes jaundice. A person with Gilbert’s syndrome has normal (straw-coloured) urine. A person with hepatitis will usually have dark urine and may also have a fever.
The processing of bilirubin
Bilirubin is the yellowish-brown pigment that gives bile its colour. It is created by the breakdown of old red blood cells by the spleen. The broken down cells are transported to the liver, where they undergo chemical changes and become the bilirubin in bile.
Bile is needed for the breakdown of fats in the intestine. The bacteria in the intestinal tract process the bilirubin further. Finally, bilirubin is excreted from the body and is responsible for the brown colour of faeces.
If a person has abnormally high amounts of bilirubin or some problem with the chemical conversion in their liver, there will be greater than normal levels of bilirubin circulating in their bloodstream.
This can cause yellowing of the skin and eyes. In a person with Gilbert’s syndrome, the bilirubin levels typically fluctuate and only sometimes hover within the normal range.
The cause is unknown
Gilbert’s syndrome is believed to be due to the reduced activity of a particular enzyme. This makes the liver less capable of processing bilirubin.
The cause of the poor enzyme function is unknown, but there is a family history in most cases. Therefore, Gilbert’s syndrome is considered an inherited disorder.
Do I need any tests?
Yellowing of the skin and the whites of your eyes (jaundice – a high level of bilirubin) can be caused by many different diseases of the liver and blood. Therefore, if you develop jaundice you are likely to need tests to clarify the cause and to rule out serious disease.
A blood test can usually confirm the diagnosis of Gilbert’s syndrome. It shows a mildly raised level of bilirubin, but with all the other liver tests being normal.
Rarely, other tests such as a liver biopsy may be done to rule out liver diseases if the diagnosis is in doubt. You may also be offered genetic testing.
Gilbert’s syndrome is also commonly diagnosed by chance when routine blood tests that are done for other problems show a raised level of bilirubin.
Diagnosis of Gilbert’s syndrome
In many cases, Gilbert’s syndrome is so mild that there are no obvious symptoms. It is often diagnosed by accident when blood tests are ordered to investigate an unrelated condition.
In other cases, Gilbert’s syndrome may be accompanied by symptoms similar to more serious liver diseases, so thorough medical investigation is needed.
Diagnostic tests include:
- Medical history
- Physical examination
- Blood tests
- Urine tests
A genetic test exists that can detect the gene that causes Gilbert’s syndrome, but this is not usually necessary for a diagnosis and is not widely available.
What is the treatment for Gilbert’s syndrome?
No treatment is needed. People with Gilbert’s syndrome normally lead healthy lives. Life expectancy is not affected and life insurance is not affected.
Mild yellowing of the skin and the whites of the eyes (jaundice) may recur from time to time for short periods, but usually causes no health problems.
The take home message is – Gilbert’s syndrome is really a mild abnormality of how the liver processes a chemical called bilirubin. It is not really a ‘disease’ and does not normally cause problems.