The use of rAra (Phadia) tests helps detect 5 antibodies (IgE) in the blood involved in allergic reactions to peanuts. Aras are the main allergens in peanuts.
Exposure to some of these Aras is associated with severe reactions, while others indicate the possibility of a cross-allergy with other legumes, tree nuts or birch pollen. A measurement of total anti-peanut IgE does not distinguish between these different possibilities. The interpretation chart accompanying the result expresses the probability of an allergic reaction to each of these specific peanut components, but not the severity of the reaction. Case history, clinical examination by the physician and the level of each IgE, including total anti-peanut IgE levels, are essential for obtaining a reliable interpretation of the results.
When only Ara h8 is present, it is more likely that the individual is actually allergic to birch pollen and that the symptoms are limited (oral syndrome). The presence of Ara h2 (and to a lesser extent Ara h1, h3 and h9) generally confirms a real and severe allergy to peanuts, and the risks of a severe systemic reaction are significant even with exposure to a very small quantity of peanuts.