New test to determine peanut allergy is very effective
A peanut allergy is a dangerous disease that can even lead to death. 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 cheaply and easily identify peanut allergies in children.
Scientists at the internationally respected King’s College London have developed a new blood test that can quickly, cheaply and reliably diagnose peanut allergies in children. The doctors published the results of their current study in the English-language journal "Journal of Allergy and Clinical Immunology".
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 revealed a correct diagnosis in 98 percent of the subjects in the study with 174 participating children.
Previous tests are inaccurate
A peanut allergy is usually confirmed by an unreliable so-called prick test on the skin and oral nutrition tests (a time-consuming process in which ever larger quantities of peanuts are fed from parents to their children). The new test is five times cheaper than mother feeding. And the tests so far are not ideal. If doctors were to 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 who have a positive test for peanuts are actually allergic to eating in a monitored environment, the expert adds.
New test can confirm diagnoses
The new blood test could act as a reliable tool if prick tests are inconclusive and affected children should actually do a nutritional test. The new test is specific to confirming the diagnosis. If it turns out positive, we can be sure that it is an allergy. The number of expensive, stressful, oral food tests would be reduced by two-thirds and affected children are prevented from experiencing unpleasant allergic reactions, the scientists 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 narrowing of the throat and airways. These symptoms are triggered when food proteins interact with an antibody called immunoglobulin E. The standard skin prick tests measure the presence of these antibodies. The new test focuses on mast cells that are activated by immunoglobulin E in the blood plasma. These produce biomarkers for allergic reactions and can then be detected in the laboratory, explain the doctors.
More research is needed
Scientists are already working on expanding their research work in order to be able to effectively diagnose other food allergies. The test is now to be adapted to other foods such as milk, eggs, sesame and nuts, explains Dr. Santos. This test will prove to be very useful, the researchers hope. So far, parents have often been afraid to give their children food that is known to cause allergic reactions. With the test, they would know which foods actually need to be avoided. (As)