[Food-induced anaphylaxis. A new French multicenter study].

The frequency of food-induced anaphylactic shocks (FIAS) has been investigated beside 46 emergency departments, 29 departments of Dermatology, and 19 departments of Intern Medicine or Pneumology. 794 A.S. have been reported. FIAS represent 10.2% of the etiologies. More than a third of them are relapsing anaphylaxis. Food allergy had been previously identified in 23.4% of cases. The allergen was present as a hidden allergen or inadvertently consumed in 30.8% of FIAS. 9.9% of the patients were asthmatic. An enhancing factor was heightened in 25.9% of cases: alcohol, exercise, simultaneous intake of aspirin, beta-blockers, conversion enzyme inhibitors. Other factors predisposing to food anaphylaxis were a cross-reactivity shared by pollens and fruit, latex and exotic fruit, house dust mites and snails, or mastocytosis. More than 15 allergens were detected: egg (11.6%), fish (10.4%), crustaceans (10.4%), milk (6.5%), fruit-latex group (6.5%), peanut and other legumes (soy, peas, lentils, guar gum...), celery, garlic, etc... The food allergen still remained unknown in 25% of cases. However, the rate of efficiency of the diagnosis reached 94% in the Allergy Units. In addition 10.2% of A.S. were considered idiopathic, raising the hypothesis of allergy to masked food allergens. Compared to a previous study from the 1982's, this survey shows a striking increased prevalence of FIAS. The frequency of recurrent anaphylaxis, occurring in one-third of cases, is also highlighted and makes plausible once more the role of masked food allergens. The authors insist upon the need of a thorough allergologic investigation in all the cases of A.S. An informative labelling about the presence or absence of food proteins which are mostly allergenic should be recommended. The need of a thorough allergologic investigation is supported not only by the incidence of FIAS but also by the incidence of idiopathic anaphylaxis: 10.2%.