Sensitization to nut allergens in children with food allergy and other atopic diseases - just a coexistence?

Introduction: Allergy to nuts, the most common food allergy in childhood, is considered as a significant health problem. Aim: To investigate sensitization to selected nuts in children with or without atopic allergy. Material and methods: Retrospective analysis involved records of 598 children, diagnosed with food allergy. Laboratory data concerned screening for sensitization to major allergens of hazelnut, peanut and walnut. Results: Approximately 77.8% of children with food allergy presented at least one concomitant atopic disease: allergic rhinitis (52.9%), atopic dermatitis (48%) or asthma (31.4%). Nearly one-third experienced at least one episode of anaphylaxis. The nut-specific antibodies were found in 67% of children. Among them, 56% were sensitized to hazelnut, and 54% to peanut. Sensitization to other nuts was less frequent (< 30%). Only 27% of patients were mono-sensitized, the remaining 73% were co-sensitized to two or three of tested nuts. Noteworthy, the occurrence of sensitization varied among age-related groups, and also depended on clinical diagnosis. In patients with sole food allergy the frequency of sensitization was highest in youngest children, whereas, when accompanied by other atopic disease, it was highest in schoolchildren. In children without food allergy, but with another atopic disease, the prevalence of sensitization was relatively low, without any specific pattern. Conclusions: The analysis of sensitization patterns may help to identify patients with an increased risk, and gives the opportunity to introduce more effective prophylaxis. However, since even the first exposure to nuts may be sufficient to trigger the anaphylaxis, this risk should be considered as a serious issue at any age.