Liver disease can develop quietly for years, often without causing obvious symptoms.
Researchers at The University of Toledo have developed a simple blood test that may help identify an early warning sign before serious liver damage becomes apparent.
The liver is one of the body’s most important organs. It processes nutrients, helps remove harmful substances, makes important proteins and produces bile, which helps the body digest fats.
Many liver conditions cause few symptoms in their early stages. By the time a person develops tiredness, abdominal discomfort, yellowing of the skin or other noticeable problems, the disease may already have progressed.
This makes early detection especially important. Finding liver trouble sooner may give patients more time to make lifestyle changes, receive treatment or undergo further testing before permanent damage develops.
Researchers Dr. Matam Vijay-Kumar and Sadhana Kumari focused on substances called bile acids. These are made by the liver and normally travel into the digestive system, where they help the body absorb fats and certain vitamins.
Only small amounts of bile acids should normally be found in the bloodstream. When the liver is not working properly or the normal flow of bile becomes blocked, bile acids can build up in the blood.
This condition is known as cholemia. Importantly, rising bile acid levels can occur before a person feels ill and before some commonly used liver tests become clearly abnormal.
Routine blood panels may measure substances such as bilirubin, cholesterol and triglycerides. Doctors can also order liver enzyme tests, but bile acids are not commonly included in standard annual bloodwork.
Vijay-Kumar argues that this may represent a missed opportunity. He believes measuring or screening for elevated bile acids could help doctors identify some liver problems earlier.
The researchers did not initially set out to develop a screening test. They were studying how high levels of bile acids affect red blood cells, which carry oxygen around the body.
Because bile acids can interact with the fatty outer layer of cells, the scientists expected exposed red blood cells to become easier to break apart. Instead, they discovered the opposite.
Red blood cells from mice with high bile acid levels were unusually resistant to bursting when placed under certain conditions. The researchers observed this pattern across several mouse models with elevated bile acids.
They then examined whether the same effect occurred in people. The team studied blood from 23 patients with cholestatic liver disease treated at the University of Toledo Medical Center.
The samples were compared with blood from 23 people of similar age and sex who showed no signs of liver disease. The same unusual resistance in red blood cells appeared in patients with elevated bile acids.
The researchers found a possible explanation. Exposure to high bile acid levels changed the outer membrane of red blood cells, increasing its cholesterol content while reducing another major type of fat in the membrane.
This change made the cell membrane more rigid. Because of that increased stiffness, the cells reacted differently when exposed to a solution designed to place them under stress.
The team realized that this response could potentially become a quick screening method. According to Vijay-Kumar, only a tiny additional amount of blood would be needed, and the test could provide a result within about 10 to 20 minutes.
The researchers say the method was able to distinguish people with elevated bile acids from those without signs of liver disease with high accuracy in their study. However, the test is still experimental and is not yet a routine diagnostic test.
A positive result would also not prove that a person has a particular liver disease. Instead, it could alert doctors that bile acids may be elevated and that additional liver testing is needed.
One group that could potentially benefit is pregnant women at risk of intrahepatic cholestasis of pregnancy. This condition causes bile acids to rise during pregnancy and can create serious risks for the unborn baby when levels become very high.
Elevated bile acids can also occur in drug-related liver injury and many other medical conditions. The researchers say bile acid changes have been reported in numerous clinical situations but are often not used as an early diagnostic clue.
The research was published in the American Journal of Physiology—Gastrointestinal and Liver Physiology. The University of Toledo Technology Transfer Office has also filed a patent application covering the rapid blood-screening concept.
The study is interesting because it turns an unexpected change in ordinary red blood cells into a possible signal of hidden liver stress. The test also appears relatively simple and could potentially be added to blood collection already being performed for other reasons.
However, the human part of the study was small, involving only 46 people in total. Much larger and more diverse studies will be needed to establish how accurately the test works across different liver diseases, ages and health conditions.
Researchers must also determine how often the test produces false alarms and whether it detects disease early enough to improve treatment outcomes. A useful screening test needs to do more than identify an unusual blood result—it needs to help doctors make better decisions.
For now, the work provides a promising new approach rather than a replacement for existing liver tests. If future studies confirm the findings, a small extra blood sample could one day help doctors notice liver trouble at a stage when patients still feel completely well.
Source: The University of Toledo
