Basophil Activation Test (BAT) Sensitivity in Child Food Allergy

Child food allergy represent 6 to 8% of child in industrialised country. Within this allergy, peanuts and egg allergy are one of the most common. Actually when there is a suspicion of food allergy, the OPT is the gold standard for the diagnosis. During the OPT we give increasing doses of the allergen to the patient and evaluate threshold causing a clinical reaction. This test is associated with a risk of strong allergic reaction and need a medical supervision. Standard allergy test, like skin test or specific IgE test, can't be use for the diagnosis of these allergy. Some publications demonstrate that these tests lack sensibility and specificity for child food allergy diagnosis. New tests have to be develop to diagnosis child food allergy without risks. The BAT is a cellular test able to evaluate the basophiles activation by specific allergen in vitro. This test allow us to evaluate more physiologically the sensitization of patients to an allergen. It is already used in drug allergy and it has been evaluated in infant milk allergy in an other clinical trial. In this study we want to evaluate the sensitivity of BAT to the diagnosis of child food allergy compare to the gold standard test OPT. We will evaluate the BAT on 140 children with food allergy and compare this results with the OPT at the same time. If the BAT results can predict the sensitivity of children to food allergen, it could limit the use of the OPT and reduce the risk of this test.