Southampton researchers helped develop a new tool to diagnose a progressive form of the often ‘silent’ disease non-alcoholic fatty liver disease.
Prof Christopher Byrne at the NIHR Southampton Biomedical Research Centre worked with colleagues in Italy and China to develop the ultrasound technique. It could be used for early diagnosis to prevent irreversible liver damage.
‘Silent’ liver disease
Non-alcoholic fatty liver disease (NAFLD) is the term for a range of conditions caused by a build-up of fat in the liver. It's usually seen in people who are overweight or obese, and is estimated to affect around 25% of the world’s population.
It has four stages, where the liver becomes progressively more damaged. The first stage, steatosis, involves a largely harmless build-up of fat in the liver. Most people do not know they have it.
However, if untreated it can progress to the next stage, non-alcoholic steatohepatitis (NASH), which is a more serious form of the disease where the liver becomes inflamed.
NASH can then progress to the third stage, fibrosis, where persistent inflammation causes scar tissue around the liver and nearby blood vessels. The liver is still able to function normally.
The final stage is cirrhosis. This is the most severe stage, occurring after years of inflammation. The liver shrinks and becomes scarred and lumpy. This damage is permanent and can lead to liver failure, where the liver stops working properly.
Finding a better diagnostic tool
Currently, NASH is usually diagnosed by a biopsy to remove a small piece of liver which is analysed in a laboratory.
In this study, published in Liver International, the researchers looked to find a better diagnostic tool to diagnose NASH. Such a tool would enable people at risk to be diagnosed much more easily, allowing them to make changes to their lifestyle.
Changes such as doing more exercise and eating a healthier diet could prevent their NAFLD from progressing to the later stages, when liver damage becomes permanent and irreversible.
Such lifestyle changes may even be able to reverse some of the damage. People with NASH who lose more than 10 percent of their weight can remove some fat from the liver and improve their condition.
Testing quantitative ultrasound
The researchers investigated whether quantitative ultrasound, currently used to diagnose bone conditions such as osteoporosis, could be used for people with NASH.
This technique measures the density of a body tissue - in this case liver tissue - by determining how rapidly high-frequency sound waves travel through it and are absorbed.
They tested it on 259 Chinese people diagnosed with NAFLD using a biopsy. Using the two most useful predictive features from the quantitative ultrasound, they developed a scoring system.
Then they trialled this scoring system to see if it was able to identify those with NASH, and found it was able to effectively select those with the condition.
Prof Byrne, Professor of Endocrinology and Metabolism and Honorary Consultant Diabetologist & Metabolic Physician, said:
“This research, while still in the early stages, shows it is possible to use quantitative ultrasound to diagnose NASH without the need for a biopsy or other invasive procedures.
“Rates of NAFLD are extremely high worldwide. If used as a diagnostic tool, this could allow many more people to be diagnosed at an early stage, when lifestyle changes can still prevent and even reverse the damage to the liver.”