Grass-Allergic Children Frequently Show Asymptomatic Low-Level IgE Co-Sensitization and Cross-Reactivity to Wheat.

BACKGROUND: Specific immunoglobulin E (IgE) sensitization to wheat is more common than a doctor's confirmed wheat allergy and is also frequently observed in grass pollen-allergic patients (pollinosis patients). Thus, the objective of this study was to investigate the level and feature of serological IgE cross-reactivity between grass pollen and wheat in a cohort of pollinosis subjects with no diagnosis of wheat allergy. METHODS: Seventy-two children, aged 5-17 years, with a doctor's diagnosis of pollinosis, IgE towards grass pollen, and currently eating wheat were recruited. Serum samples were analyzed for IgE against wheat, timothy grass/wheat-specific allergen components, Pru p 3, and cross-reactive carbohydrate determinants (CCD) and specific IgE-binding inhibition experiments were performed. RESULTS: Sixty percent of the grass pollen subjects were sensitized to wheat with a median of 0.5 kUA/L. Wheat-sensitized subjects were more often sensitized to the two allergens, Phl p 12 and CCD, known to be cross-reactive between grass and wheat. Sensitizations to seven wheat-specific allergens derived from the gluten fraction were, with the exception of one individual, only found in wheat-sensitized subjects. These subjects also more often reported current and past history of allergy to staple foods (milk, egg, wheat, soy, and fish). CONCLUSION: Wheat sensitization caused by cross-reactivity but also by sensitization to wheat-specific allergens was common in the grass-allergic children and also associated with allergy to staple foods other than wheat. The results indicate the presence of a subgroup of pollinosis patients with simultaneous sensitization to wheat and food allergy not only caused by cross-reactions.

Parents' perceptions are that their child's health-related quality of life is more impaired when they have a wheat rather than a grass allergy.

AIM: It is unknown whether food allergies have greater impact on quality of life than respiratory allergies. This study compared health-related quality of life (HRQoL) in children allergic to wheat or grass. METHODS: We surveyed 63 children with wheat allergies (median age of five) and 72 with grass allergies (median age 12), with their parents. The Child Health Questionnaires for parents (CHQ-PF28) and children (CHQ-CF87) were applied. RESULTS: The parents of children in the wheat group recorded significantly lower CHQ-PF28 scores for the impact of their child's allergy on general behaviour, general health perceptions, parental impact of emotions and time and family activities, than the parents of children with grass allergies (p values ≤0.001). However, parents in the grass group recorded lower scores for the change in health item than the parents of children with wheat allergies (p = 0.020). In the grass group, children and parents reported similar scores for the different questions, but there was poorer correlation between parents and children in the wheat allergy group. CONCLUSION: HRQoL was lower in children with wheat than grass allergies according to parental reports, with more consistent perceptions of HRQoL among parents and children in the grass allergy than wheat allergy group.

Wheat allergy in children evaluated with challenge and IgE antibodies to wheat components.

INTRODUCTION: Wheat sensitization is common but IgE antibodies (IgE-abs) to wheat are not predictive of clinical symptoms in children with suspected wheat allergy. Wheat allergen components other than ω-5 gliadin have not been well studied. Our aim was to characterize the clinical profile and investigate the value of adding measurements of IgE-abs to wheat components in a group of children with a doctor's diagnosed wheat allergy. METHOD: Sixty-three children with a doctor's diagnosis of wheat allergy confirmed sensitization to wheat and, on a wheat elimination diet, went through oral wheat challenges or had a convincing recent history of wheat allergy. IgE-ab to ω-5 gliadin, low molecular weight glutenin (LMW-glutenin), high molecular weight glutenin (HMW-glutenin) and a native gliadin preparation containing α-, ß-, γ-, and ω-gliadin (gliadin) were analyzed. RESULTS: Twenty-six children were positive in challenge, while six children were regarded as wheat allergic due to recent anaphylactic reactions. The IgE-ab levels to all four wheat components were significantly higher in the group with wheat allergy compared to the group with no wheat allergy (p < 0.0001). Also, the severity of symptoms at challenge correlated with the IgE-ab levels to all four components (p < 0.05). IgE-ab levels to ω-5 gliadin correlated best with challenge outcome, and by additional analysis of gliadin, HMW- and LMW-glutenin IgE-abs all challenge positive children could be identified. CONCLUSION: Many children diagnosed as wheat allergic have outgrown their allergy and are unnecessarily on a wheat-free diet. The levels of IgE-ab to wheat gluten-derived components correlated well with wheat challenge outcome and severity.