Diagnosis of food allergy due to peanuts

Allergy due to peanuts is a frequent food allergy, involving about 1% of the population. It is a potentially severe allergy, usually persistent and having a strong impact on the quality of life of the patients and their entourage. The diagnosis is based on the clinical history, the results of skin tests plus serum assays for peanut-specific IgEs and its allergens. Confirmation of the diagnosis is established by a double-blind, placebo-controlled oral provocation test. Based on a review of the literature, we evaluated the place of different tests, used in the diagnostic workup and we propose a decisional algorithm for food allergy due to peanuts. The suspicion of this allergy is established on the basis of a compatible clinical history and a positive skin prick-test to peanut (either a real peanut or a peanut extract). The diagnostic algorithm depends on the initial level of IgE specific for rAra h2 and rAra h6, which if positive, establishes the diagnosis of food allergy due to peanuts with a sensibility of 98% and a specificity of 96%. If the results are negative, then IgE assays for rAra hland rAra h3 and subsequently for rAra h9 are justified. The presence of anti-rAra h8 IgE is a sign of the existence of cross-reactivity with pollens. A repeat oral introduction test may be done, following the PRACTALL consensus recommendations. This allows us to determine the level of reactivity, to implement an avoidance regime, to follow the evolution of the food allergy and to define the details of a dietary regimen. (C) 2015 Elsevier Masson SAS. All rights reserved.