Scientists developed a new test to diagnose peanut allergy, according to a study conducted on May 3, 2018.
This study was conducted by the scientists of the Medical Research Council. The newly developed test, called as mast activation test (MAT), has 98 per cent specificity and unlike the methods that are currently available for the diagnosis of peanut allergy, this test does not cause allergic reactions such as anaphylactic shock to the patients. When compared to the oral food challenge (OFC), this blood test is five times more cost-efficient and is also recommended for the tests of other food allergies.
Peanut allergies are one of the most common food allergies observed in children. Currently, peanut allergy is diagnosed using a skin-prick test or IgE test, which might result in over-diagnosis or false-positives. Moreover, this conventional method cannot differentiate between sensitivity and true food allergy. When skin-prick and IgE test results are unclear, allergists rely on an OFC. In this method, peanut, in incrementally larger doses, is fed to the patient in a highly-controlled setting in hospital to confirm allergy to the food. Although this test is being used for diagnosing food allergies since a long time, risk of causing severe allergic reactions is high. The newly developed test is a solution to this problem.
The new test focuses on mast cells, which play a crucial role in triggering allergic reactions. Mast cells are activated when the IgE in plasma are recognized and, in allergic patients, produce biomarkers associated with allergic reactions, which can be detected in the lab.
The study was conducted by collecting blood samples of 174 children, 73 peanut allergic and 101 peanut-tolerant, who were a part of the allergy testing. Peanut protein was added to the mast cells by the scientists to screen for IgE-mediated activation. Peanut allergy was accurately identified by the MAT with 98 specificity. The scientists are planning to take the biomarker test into a clinical setting.