An algorithm for diagnosing IgE-mediated food allergy in study participants who do not undergo food challenge.

BACKGROUND: Food allergy diagnosis in clinical studies can be challenging. Oral food challenges (OFC) are time-consuming, carry some risk and may, therefore, not be acceptable to all study participants. OBJECTIVE: To design and evaluate an algorithm for detecting IgE-mediated food allergy in clinical study participants who do not undergo OFC. METHODS: An algorithm for trial participants in the Barrier Enhancement for Eczema Prevention (BEEP) study who were unwilling or unable to attend OFC was developed. BEEP is a pragmatic, multi-centre, randomized-controlled trial of daily emollient for the first year of life for primary prevention of eczema and food allergy in high-risk infants (ISRCTN21528841). We built on the European iFAAM consensus guidance to develop a novel food allergy diagnosis algorithm using available information on previous allergenic food ingestion, food reaction(s) and sensitization status. This was implemented by a panel of food allergy experts blind to treatment allocation and OFC outcome. We then evaluated the algorithm's performance in both BEEP and Enquiring About Tolerance (EAT) study participants who did undergo OFC. RESULTS: In 31/69 (45%) BEEP and 44/55 (80%) EAT study control group participants who had an OFC the panel felt confident enough to categorize children as "probable food allergy" or "probable no food allergy". Algorithm-derived panel decisions showed high sensitivity 94% (95%CI 68, 100) BEEP; 90% (95%CI 72, 97) EAT and moderate specificity 67% (95%CI 39, 87) BEEP; 67% (95%CI 39, 87) EAT. Sensitivity and specificity were similar when all BEEP and EAT participants with OFC outcome were included. CONCLUSION: We describe a new algorithm with high sensitivity for IgE-mediated food allergy in clinical study participants who do not undergo OFC. CLINICAL RELEVANCE: This may be a useful tool for excluding food allergy in future clinical studies where OFC is not conducted

The Influence of Dietary Factors on Child Food Allergies

Solid food introduction guidelines were recently amended to suggest that earlier introduction of peanuts is associated with a decreased prevalence of peanut allergies in high-risk children. This study aimed to determine whether there is a relationship between timing of introduction to the eight most common food allergens and the development of a food allergy. A total of 177 biological mothers of school-aged New Hampshire children completed the survey, but some were excluded due to answering \u3c50% of the survey or not consenting to participate in the study. This left data on 101 participants, and the number of participants then varied between the various food allergens. Out of the 22 children with a milk allergy, 10 children were introduced to milk when they were less than 12 months old and 12 children were introduced at or after one year old. Fifty-nine percent of those introduced before 12 months of age developed a milk allergy, while only 17% of those introduced at or past 12 months developed a milk allergy (p = 0.00). Out of the 55 participants that developed a peanut/tree nut allergy, 12 were introduced to peanuts/tree nuts before the age of 12 months, and 43 introduced after. This means that 63% of those introduced before a year developed an allergy, while only 33% introduced later developed an allergy (p = 0.01). Although not significant, the results for egg, wheat, and peanut also demonstrated that earlier introduction may be associated with an increased risk of an allergy to that food. When only one child per family was considered, to exclude genetic confounders, the only significant value was for a milk allergy, in which 64% of children introduced before 12 months developed a food allergy, while only 18% of children introduced at or after 12 months developed one (p = 0.00). Results were similar even after the exclusion of child one and two. The results of this study concur with the recommendation of introducing milk after one year, but do not support earlier introduction to other food allergens in the general population

What's new in the diagnosis and management of food allergy in children?

This article reviews the recent advances in the diagnosis and management of IgE mediated food allergy in children. It will encompass the emerging technology of component testing; moves to standardization of the allergy food challenge; permissive diets which allow for inclusion of extensively heated food allergens with allergen avoidance; and strategies for accelerating tolerance and food desensitization including the use of adjuvants for specific tolerance induction

Explaining adherence to self-care behaviours amongst adolescents with food allergy: a comparison of the health belief model and the common sense self-regulation model

OBJECTIVES: To identify explanations for adherence to self-care behaviours amongst adolescents with food allergy-induced anaphylaxis using two social cognition models: the health belief model (HBM) and the common sense self-regulation model (CS-SRM). DESIGN: Cross-sectional self-completion questionnaire study to gain initial evidence of the two models' feasibility/effectiveness in explaining adherence in an adolescent food-allergic population. METHODS: Participants aged 13-19 years with a diagnosis of severe food allergy and a prescription of an adrenaline auto-injector were recruited from hospital outpatients. Adherence to self-care behaviours was measured in addition to constructs from the HBM and CS-SRM. RESULTS: One hundred and eighty-eight food-allergic adolescents completed the questionnaire. The HBM, specifically the constructs perceived severity and barriers, accounted for 21% of the explained variance in adherence behaviours. CS-SRM constructs, illness identity, timeline cyclical beliefs and emotional representations explained 25% of the variance. CONCLUSIONS: Both models performed similarly in explaining adherence to self-care behaviours in adolescents with food allergy. Interventions designed to elicit personal barriers to adherence and to address perceptions of severity and the unpredictable nature of symptoms may be more effective in improving adherence to self-care behaviours than current interventions. STATEMENT OF CONTRIBUTION: What is already known on this subject? Patients' poor management of food allergy induced anaphylaxis is commonly attributed to lack of knowledge and ability in using the adrenaline auto-injector. Adherence to recommended preventive self-care behaviours, like allergen avoidance and carrying emergency medication, are rarely assessed. Social Cognition Models (SCMs) have been successfully applied to a number of adherence-related studies in disease conditions such as asthma and diabetes, but have not yet been applied to food allergy induced anaphylaxis. What does this study add? This is the first large-scale quantitative study of adherence behaviours in adolescents with food allergy. This is the first study to apply theoretical models to explain adherence in the adolescent food allergic population. This is the first application of both models to food allergy, and the first to compare the two models' measurement instruments

Introducing Allergenic Food into Infants\u27 Diets: Systematic Review

Purpose: The purpose of this systematic review was to explore the association between timing of introduction of potentially allergenic foods to infants and development of food allergies. Methods: CINAHL, Medline, PubMed, Science Direct, and Web of Science were searched using the terms solid food, complementary food, or infant feeding combined with allergy or hypersensitivity for articles published in English in 2000 or later. Inclusion criteria were 1) primary research articles with 2) a focus on association between introduction of complementary foods including potentially allergenic foods into diets of infants less than 12 months of age and development of food allergies. Articles were excluded if they were 1) not primary research, 2) about complementary foods only (without specifi city of allergenic foods), or 3) on allergic conditions other than food allergy (such as asthma or eczema). Results: The initial literature search yielded 533 articles; 14 articles met inclusion criteria. Level of evidence of each study was determined with the SORT criteria. Results found that delayed introduction of solid foods in general and allergenic foods in particular was not associated with decreased risk for allergic diseases among high and low-risk infants. Later introduction was associated with increased risk for allergy development. Clinical Implications: For infants at low risk for development of food allergies, providers should advise caregivers to introduce potentially allergenic foods with other solid foods between 4 and 6 months of age when children show an interest in eating solids. Infants at high risk for peanut allergy, should be evaluated by an allergy specialist prior to introduction of peanuts and work with providers to create an individualized plan for introduction of peanuts and other allergenic foods as needed

Release of Mast Cell Tryptase into Saliva: A Tool to Diagnose Food Allergy by a Mucosal Challenge Test?

Background: Our aim was to examine whether measurement of the saliva mast cell tryptase (MCT) concentrations before and after a mucosal challenge test with the offending food would be helpful in diagnosing food allergy. Methods: We performed a retrospective analysis of 44 food challenge tests performed in 38 patients between 2006 and 2009. Patients with a suspected history of food allergy chewed the food until they developed symptoms or until the amount of time known from the patients' history to usually be required for the provocation of symptoms had passed. In 5 patients, saliva samples for the measurement of MCT were collected at minutes 0, 1, 4, 8, 11, and 16 after the first onset of symptoms. The remainder of the patients only had samples taken before chewing and 4 min after the end of the test period. Results: During repeated measurements, MCT peaked about 4 min after the onset of symptoms (p = 0.028). During 33 of the 44 tests (75.0%), we observed oral symptoms during testing; after 25 of the 33 (75.8%) tests evoking symptoms, the saliva MCT concentration increased. The MCT increase was negative in all other tests where no oral symptoms could be provoked. Conclusions: The measurement of saliva MCT 4 min after the onset of symptoms may be helpful to diagnose food allergy. Because of numerous confounding variables, however, a negative saliva MCT increase does not exclude food allergy. Copyright (C) 2011 S. Karger AG, Base

Recent advances in understanding and preventing peanut and tree nut hypersensitivity.

Peanut allergy, the most persistent and deadly of the food allergies, has become more prevalent worldwide in recent decades. Numerous explanations have been offered for the rise in peanut allergy, which has been more pronounced in Western, industrialized nations. In infants who are at increased risk of peanut allergy, new evidence indicates that early introduction of peanuts can help prevent allergy development. This counterintuitive finding directly contradicts the previously established practice of peanut avoidance for high-risk infants but is supported by clinical and basic science evidence. Here, we review the literature contributing to our evolving understanding of nut allergy, emphasizing the translation of this work to clinical practice

The main problems of food allergic consumers concerning food labeling: an ethnographic study

It has been estimated that 58% of children and 12% of the adults in developed countries are affected by food allergy, with symptoms ranging from discomfort to fatality. At present, avoidance of problematic foods is the only effective treatment strategy. As of November 25 th , 2005 food manufacturers in the EU are obliged to list 12 potentially allergic ingredients in food. Although the label is still not always fully understood by the consumer, or they get confused by precautionary labelling practices. This paper aims to gain insights into the information preferences of food allergic consumers regarding existing food labelling and additional information delivery systems. The results of this study will facilitate the development of best practices in information provision regarding food safety in the area of food allergy. In particular the research will elicit preferences for new ICT approaches to information delivery which can be focused on the individual needs of consumers. We argue that improved information supply will contribute to the quality of life of food allergic people.Food allergy, consumers, food labelling, information needs, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,