A blood test could detect NAFLD before liver damage

Chemical compounds produced by the bacteria in our gut could be used to spot the early stages of liver disease, according to new research by Imperial College London.

The study, which has been published in the journal Nature Medicine, investigates the link between early stages of Non-Alcoholic Fatty Liver Disease (NAFLD) and the microbiome – made up of trillions of bacteria, viruses and other microbes living in our digestive tract.

NAFLD starts with the build-up of fat in liver and can lead to scarring and cirrhosis, where the scarred organ eventually shrinks and the risks of liver failure and cancer increase. Fatty liver also increases the risk of developing type 2 diabetes and cardiovascular diseases.

The researchers identified a compound called phenylacetic acid (PAA), produced by bacteria in the gut and whose presence in the blood was connected with the early onset of NAFLD.

The findings suggest that PAA could be used as a biological marker, where a patient’s blood sample could be screened for PAA as an early warning sign to identify if they are at increased risk of the disease.

Dr Lesley Hoyles, the study’s lead analyst, said: ‘Through this work we may have uncovered a biomarker for the disease itself. Overall, it demonstrates the microbiome is definitely having an effect on our health.’

Dr Marc-Emmanuel Dumas, the study’s senior author, said: ‘The concept that we could use chemical signals produced by our gut bacteria to spot disease is an exciting one. It opens the possibility that simple screening test at a GP clinic could one day be used to spot the early signs of disease. But these kinds of tests may still be a number of years away from the clinic.’