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Background Eliciting doses (EDs) of allergenic foods can be defined by the distribution of threshold doses for subjects within a specific population. The ED 05 is the dose that elicits a reaction in 5% of allergic subjects. The predicted ED 05 for peanut is 1.5 mg of peanut protein (6 mg of whole peanut). Objective We sought to validate the predicted peanut ED 05 (1.5 mg) with a novel single-dose challenge. Methods Consecutive eligible children with peanut allergy in 3 centers were prospectively invited to participate, irrespective of previous reaction severity. Predetermined criteria for objective reactions were used to identify ED 05 single-dose reactors. Results Five hundred eighteen children (mean age, 6.8 years) were eligible. No significant demographic or clinical differences were identified between 381 (74%) participants and 137 (26%) nonparticipants or between subjects recruited at each center. Three hundred seventy-eight children (206 male) completed the study. Almost half the group reported ignoring precautionary allergen labeling. Two hundred forty-five (65%) children experienced no reaction to the single dose of peanut. Sixty-seven (18%) children reported a subjective reaction without objective findings. Fifty-eight (15%) children experienced signs of a mild and transient nature that did not meet the predetermined criteria. Only 8 (2.1%; 95% CI, 0.6%-3.4%) subjects met the predetermined criteria for an objective and likely related event. No child experienced more than a mild reaction, 4 of the 8 received oral antihistamines only, and none received epinephrine. Food allergy–related quality of life improved from baseline to 1 month after challenge regardless of outcome (η 2 = 0.2, P < .0001). Peanut skin prick test responses and peanut- and Ara h 2–specific IgE levels were not associated with objective reactivity to peanut ED 05 . Conclusion A single administration of 1.5 mg of peanut protein elicited objective reactions in fewer than the predicted 5% of patients with peanut allergy. The novel single-dose oral food challenge appears clinically safe and patient acceptable, regardless of the outcome. It identifies the most highly dose-sensitive population with food allergy not otherwise identifiable by using routinely available peanut skin prick test responses or specific IgE levels, but this single-dose approach has not yet been validated for risk assessment of individual patients. [ABSTRACT FROM AUTHOR]

Background: Food allergy can affect health-related quality of life (HRQL). Currently, no validated, self-administered, disease-specific HRQL questionnaire for adolescents with food allergy exists. Objective: We sought to develop and validate the Food Allergy Quality of Life Questionnaire–Teenager Form (FAQLQ-TF) in the Dutch language. Methods: Ten adolescents (13-17 years) with food allergy were interviewed and generated 166 HRQL items. The most important items were identified by 51 adolescents with food allergy by using the clinical impact method, resulting in the FAQLQ-TF containing 28 items (score range: 1 “no impairment” to 7 “maximal impairment”). The FAQLQ-TF, the Food Allergy Independent Measure, and a generic HRQL questionnaire (CHQ-CF87) were sent to 98 adolescents with food allergy for cross-sectional validation of the FAQLQ-TF. Results: Construct validity was assessed based on the correlation between the FAQLQ-TF and the Food Allergy Independent Measure (ρ = 0.57, P < .001). The FAQLQ-TF had excellent internal consistency (Cronbach α = .92) and discriminated between adolescents who differed in number of food allergies (1 vs >2 food allergies: total FAQLQ-TF score, 4.3 vs 3.5; P = 0.037) but did not discriminate between those who did or did not have reported anaphylaxis. The FAQLQ-TF correlated weakly with 6 of the 11 CHQ-CF87 scales, demonstrating convergent/discriminant validity. Conclusion: The FAQLQ-TF is the first self-administered, disease-specific HRQL questionnaire for adolescents with food allergy. It has good construct validity and excellent internal consistency and discriminates between adolescents who differ in the number of food allergies. The FAQLQ-TF is short and easy to use and might therefore be a useful tool in clinical research. [Copyright &y& Elsevier]

Background: In June 1998, the United Kingdom government suggested that atopic pregnant and breast-feeding mothers and their infants should avoid peanuts. Objective: We report the prevalence of peanut sensitization in the first school cohort (2003-2005) to have been conceived after the advice was issued. Method: A total of 1072 mother-child pairs were studied in school. Children with positive peanut skin prick test results to peanut had peanut challenges. Results: Overall, 61% of 957 mothers recalled hearing the advice about peanuts in 1998. This figure was unaffected by maternal atopic status. Only 36 mothers (3.8%) followed the Government''s advice by stopping the consumption of peanuts while pregnant. Maternal atopy had no effect on peanut consumption while breast-feeding. Mothers were less likely to change their diet if having a second or subsequent child compared with mothers having their first child (odds ratio 0.635, 95% Cis, 0.543-0.743; P < .01). Thirty children (2.8%; 95% CIs, 1.8% to 3.8%) had a positive peanut skin prick test result. Twenty children (1.8%; 95% CIs, 1.1% to 2.7%) were shown to have peanut allergy. This is the highest prevalence for peanut allergy recorded to date. Conclusions: The prevalence of peanut sensitization in this cohort is 2.8%, and peanut allergy now affects 1.8% of British children at school entry. It is difficult to ascertain any impact (either positive or negative) of the United Kingdom government advice on the prevalence of peanut allergy in British children aged 4-5 years from 2003 to 2005. Clinical implications: It remains uncertain if peanut avoidance during pregnancy and breast-feeding has any effect on the prevalence of peanut allergy in children. [Copyright &y& Elsevier]

Background Serum specific IgE or skin prick tests are less useful at levels below accepted decision points. Objectives We sought to develop and validate a model to predict food challenge outcome by using routinely collected data in a diverse sample of children considered suitable for food challenge. Methods The proto-algorithm was generated by using a limited data set from 1 service (phase 1). We retrospectively applied, evaluated, and modified the initial model by using an extended data set in another center (phase 2). Finally, we prospectively validated the model in a blind study in a further group of children undergoing food challenge for peanut, milk, or egg in the second center (phase 3). Allergen-specific models were developed for peanut, egg, and milk. Results Phase 1 (N = 429) identified 5 clinical factors associated with diagnosis of food allergy by food challenge. In phase 2 (N = 289), we examined the predictive ability of 6 clinical factors: skin prick test, serum specific IgE, total IgE minus serum specific IgE, symptoms, sex, and age. In phase 3 (N = 70), 97% of cases were accurately predicted as positive and 94% as negative. Our model showed an advantage in clinical prediction compared with serum specific IgE only, skin prick test only, and serum specific IgE and skin prick test (92% accuracy vs 57%, and 81%, respectively). Conclusion Our findings have implications for the improved delivery of food allergy–related health care, enhanced food allergy–related quality of life, and economized use of health service resources by decreasing the number of food challenges performed. [ABSTRACT FROM AUTHOR]