Allergies aux fruits

Abstract

Fruit allergies are frequent, representing for Rosaceae fruits 14 % of reported allergies and 5 % for fruits crossing with latex. They can be linked to a primary sensitization to pollens or isolated. The concept of fruit allergy is complex for the practitioner because of the difficulties in defining the fruit, variable according to classifications, the evaluation of the risk of cross-allergy and the particularities of the clinical expressions of a food allergy according to the allergens involved. This review specifies the botanical, culinary and allergological definitions of fruit, the main families of allergens responsible for food allergies, and the clinical, diagnostic and therapeutic particularities of fruit allergy. Sensitization can occur by respiratory sensitization (pollen-fruit cross-reactivity) or by primary sensitization to fruit by the digestive tract or by contact. Plant epitopes may be continuous or discontinuous. The thermal behaviour of allergens, their resistance to digestion and their stability in an acidic environment makes it possible to characterise their risk. Allergenicity often varies with the cultivar, the method of preservation, the food processing technologies used (cooking, canning, fermentation, texturisation, hydrolysis, filtration, etc.). The diagnosis is established on the basis of an algorithm based on anamnesis, prick-tests with native foods, the search for the specific IgE, the reintroduction test. The importance of using native foods for skin testing should be stressed because of the particular sensitivity of plant allergens to denaturation. The treatment is based on the removal of the offending fruit. Immunotherapy trials with fruit allergens are under study. Tolerance protocols using fruits at different cooking times are promising for thermolabile allergens.