New test can reliably diagnose peanut allergy

New test for peanut allergy detection is very effective

A peanut allergy is a dangerous disease that can even lead to the death of those affected. For this reason, it is particularly important that people with such a peanut allergy know about their illness at an early stage. Researchers have now found that a newly developed blood test can find cheap and easy peanut allergies in children.

The scientists at the internationally renowned King's College London have developed a new blood test that can quickly, cheaply and reliably diagnose peanut allergies in children. The physicians published the results of their recent study in the English-language journal "Journal of Allergy and Clinical Immunology".

Many people are allergic to peanuts. Researchers now developed a reliable test to diagnose peanut butter allergy. (Image: atoss / fotolia.com)

Test accuracy was 98 percent

The new test looks for so-called biomarkers, which are released by mast cells or white blood cells of the immune system. The test found a correct diagnosis in 98% of the subjects in the 174 participating children study.

Previous tests are inaccurate

Peanut allergy is usually confirmed by an unreliable so-called prick test on the skin and oral nutritional tests (a time-consuming process in which more and more peanuts are fed by parents to their children). The new test is five times cheaper than feeding by the mother. And the previous tests are not ideal. If physicians would rely on such tests alone, food allergies would be overdiagnosed, study author Dr. Alexandra Santos from King's College London. Only 22 percent of school-age children in the UK with a positive test for peanuts are actually allergic to eating in a supervised environment, the expert adds.

New test can confirm diagnoses

The new blood test could be a reliable tool if prick tests are not conclusive and affected children should actually do a nutrition test. The new test is specific to confirm the diagnosis. If it turns out to be positive, we can be sure that it is an allergy. The number of expensive, stressful, oral nutritional tests would be reduced by two-thirds and affected children will be prevented from experiencing unpleasant allergic reactions, the researchers explain.

Symptoms of a peanut allergy

Peanut allergies are among the most common food allergies in children. Such a food allergy has symptoms such as itchy skin, stomach cramps and a narrowing of the throat and airways. These symptoms are triggered when dietary proteins interact with an antibody called immunoglobulin E. The standard prick tests on the skin measure the presence of these antibodies. The new test focuses on mast cells, which are activated by immunoglobulin E in the blood plasma. These produce biomarkers for allergic reactions and can then be detected in the lab, explain the doctors.

Further research is needed

Scientists are already working to expand their research to effectively diagnose other food allergies. The test will now be adapted to other foods such as milk, eggs, sesame seeds and nuts, explains Dr. med. Santos. This test will prove very useful, the researchers hope. So far, parents are often afraid to give their children food that is known to trigger allergic reactions. With the test, they would know which foods actually need to be dispensed with.