‘Traffic light test’ promises to detect liver disease earlier
A new simple blood test can spot people with liver disease early enough for them to get potentially life-saving treatment, a new study shows.
BMJ Group News
What do we know already?
Currently diseases that damage the liver are difficult for GPs to spot. People often have liver diseases without it causing them noticeable health problems, until the damage has become severe. By this time, over a period of months or years, the damage can become serious enough to cause liver failure. This is when large parts of the liver become damaged beyond repair and the liver is no longer able to function.
Liver failure is a serious illness. Around 33 in 100 people who go to hospital with severe (or what doctors call end-stage) liver disease die within the first few months.
So it would be extremely valuable to have an accurate and reliable test for liver disease. Ideally, the test would help GPs weigh up who might be at risk of liver disease, and to spot liver disease early enough to avoid more serious damage or liver failure.
Researchers at the University of Southampton have been working on a test that GPs can use to detect liver disease earlier. The test looks for substances in the blood, called procollagen-3 N-terminal peptide (P3NP) and hyaluronic acid (HA), which are usually signs of liver damage. It also tests your platelet count. Platelets make up part of your blood, and a low platelet count can be a sign of liver damage.
After taking the test, people are ‘scored’ according to the results of their blood test. People who score zero are given a green light and are not thought to have any liver damage and are unlikely to die from liver disease over the next five years. People who score one are given an amber light, meaning there is at least a 50 in 100 chance of liver scarring (doctors call this fibrosis) with a higher chance of dying within five years. People who score 2 or more are given a red light, meaning they have fibrosis and may already have liver damage.
The researchers used the test in 1,038 people, and then followed them for an average of around four years, to see how accurate it was.
What does the new study say?
The test was most accurate for people with severe liver disease. The researchers looked at how many people died during the study, and compared this to how many people were predicted to die according to the results of the test. They found that:
- None of the 202 people who were rated green died, and none developed any signs of liver damage
- Of the people who were rated amber, 9 out of 267 (or around 3 in every 100) died, and around 1 in 100 developed some signs of liver damage
- Of the people who were rated red, 24 out of 172 (or 14 in every 100) died, and between 12 and 14 in 100 developed some signs of liver damage.