D2.04 - Sensitization to common food allergens in a population of portuguese children

Sensitization to food allergens is common in pediatric patients although it does not always imply food allergy. Our aim was to study food sensitization in our population and its relation to symptoms.

Retrospective study including all pediatric patients from a tertiary pediatric hospital to whom specific IgE for at least one food allergen was requested over six months. Clinical and demographic data were collected and analysed. 

We obtained 309 patients, aged 4.3 ± 4.2 years old (mean±SD), 180 (58.2%) males. Serum-specific IgE requests came from allergy department (183), pediatric departments (123) and other departments (3). Positive results were found in 150 (48.5%) cases. From allergy, 120 (65.6%); from pediatric 28 (22.8%) and two from other departments. Children evaluated in the allergy department had significantly higher positivity compared to pediatrics (p<0.0001). In 47 (31.3%), there was positivity to more than one food group. The most frequent allergen was hen’s egg (78), followed by cow’s milk (71), tree nuts (20) - with walnut being the most common (14), peanut (15), wheat (16), shellfish (15), fish (13) and peach (3). Of the positive results, 118 (78.7%) have had food allergy symptoms, with a history of anaphylaxis in 21. In 32 (21.3%) there was no report of symptoms suggestive of food allergy. In the group without food allergy symptoms the testing was performed because of eczema (12; 37.5%), recurrent isolated gastrointestinal symptoms (8; 25%), as screening (3; 9.4%), failure to thrive, recurrent urticaria and hiper-IgE syndrome (one case each), and testing reason was unknown in 6 (18.8%).  Seven (21.9%) of those children were advised for food eviction. In 9 (28.1%) there was no record of food eviction being started or not and the remaining 16 (50%) kept ingesting the tested positive foods without symptoms. 

Specific IgE should be requested carefully in children. Allergy referral, with a subsequent proper and thorough investigation, is crucial before starting food restrictions.