Asthme et allergies alimentaires : à propos de 163 observations pédiatriques

Abstract

The prevalence of food as a cause for asthma is not well known. The aim of this study was to define with standardized tests the incidence of food-induced asthma, the distribution of foods allergens in asthmatic children with food allergy. The study was carried on 163 asthmatic children with food allergy followed during average of 5.5 years. Asthma has been identified with pulmonary function tests (reversibility of FEV1 to bronchodilators) and food allergy has been documented by double-blind placebo-controlled food challenge (DBPCFC). Familial atopic disease was found in 148 children (90.7%). Inhalant sensitization was documented in 132 children (81%). Positive DBPCFC were observed in 250 of 385 challenges (65%) carried on these 163 children. The most frequent offending foods were, sometimes in association, peanut (30.6%), egg (23.1%), cow's milk (9.3%), mustard (6.9%), codfish (6%), shrimp (4.5%), kiwi fruit (3.6%), hazelnut (2.7%), cashew nut (2.1%), almond (1.5%), garlic (1.2%). Symptoms occurring during DBPCFC were cutaneous (143 cases, 59%), respiratory symptoms (58 cases, 23.9%), gastrointestinal symptoms (28 cases, 11.5%) and 15 anaphylactic shock (6.1%). Respiratory symptoms were oral allergy syndrome in 13 cases (5.3%), rhinoconjunctivitis in 15 cases (6.1%), asthma in 23 cases (9.5%). Only seven of these children had asthma only (2.8% of cases). The prevalence of asthma induced by food allergy is low. In our study, asthma induced by food allergy concerned 9.5% of cases and asthma alone was identified in only 2.8% of cases. We observed new food allergens associated with respiratory symptoms such as kiwi fruit, tree-nuts (hazelnut, cashew) and spices. Diagnosis relied upon data obtained from history, skin prick-tests and specific IgE. Oral food challenge is the corner stone of the diagnosis. Asthma induced by food allergens is potentially severe leading to prescribe to these patients a first aid kit with bronchodilators and epinephrine auto-injectors.