Food allergy: Epidemiology, pathogenesis, diagnosis, and treatment.

This review focuses on advances and updates in the epidemiology, pathogenesis, diagnosis, and treatment of food allergy over the past 3 years since our last comprehensive review. On the basis of numerous studies, food allergy likely affects nearly 5% of adults and 8% of children, with growing evidence of an increase in prevalence. Potentially rectifiable risk factors include vitamin D insufficiency, unhealthful dietary fat, obesity, increased hygiene, and the timing of exposure to foods, but genetics and other lifestyle issues play a role as well.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2013.

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin diseases that were reported in the Journal in 2013. Studies on food allergy suggest that (1) 7.6% of the US population is affected, (2) a "healthy" early diet might prevent food allergy, (3) the skin might be an important route of sensitization, (4) allergen component testing might aid diagnosis, (5) the prognosis of milk allergy might be predictable through early testing, (6) oral or sublingual immunotherapy show promise but also have caveats, and (7) preclinical studies show promising alternative modes of immunotherapy and desensitization.

The utility of peanut components in the diagnosis of IgE-mediated peanut allergy among distinct populations.

Background: Increasing data suggest that analysis of IgE to peanut components can be clinically helpful and possibly more accurate than IgE to whole peanut. Not all studies examining this topic, however, have used prospective samples, multiple components, and peanut challenges.

Objective: We sought to determine the utility of peanut component testing, using a standardized, commercially available test done before oral peanut challenge in various populations of patients with suspected peanut allergy from 2 different countries.

Growth and nutritional concerns in children with food allergy.

Purpose Of Review: To describe the potential effect that avoidance diets for food allergy may have on nutrition and growth in children.

Recent Findings: We report here the findings from the previous studies suggesting impairment of growth and nutritional deficiencies because of elimination diets for food allergy. Feeding difficulties have also been reported, particularly in children with eosinophilic esophagitis that may further impact the nutrient intake.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2012.

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin diseases that were reported in the Journal in 2012. Studies support an increase in peanut allergy prevalence in children and exposure to the antibacterial agent triclosan and having filaggrin (FLG) loss-of-function mutations as risk factors for food sensitization. The role of specific foods in causing eosinophilic esophagitis is elucidated by several studies, and microRNA analysis is identified as a possible noninvasive disease biomarker.

The prevalence and characteristics of food allergy in urban minority children.

Background: Urban minority children are known to have high rates of asthma and allergic rhinitis, but little is known about food allergy in this population.

Objective: To examine the prevalence and characteristics of food allergy in an urban pediatric population.

Methods: A retrospective review of electronic medical records from children seen in the hospital-based general pediatric clinic at Mount Sinai Hospital serving East Harlem, NY, between July 1, 2008 and July 1, 2010 was performed.

Nonallergen-specific treatments for food allergy.

Purpose Of Review: This review summarizes recent reports on nonallergen-specific therapies for food allergy. These therapies are especially appealing for food allergy because unlike allergen-specific immunotherapy, they would allow the treatment of multiple food allergies in a single patient with one therapy.

Recent Findings: Chinese herbal therapy, anti-IgE, probiotics, engineered lactic acid bacteria, and helminth therapy are all examples of allergen nonspecific therapies that have been investigated in recent years.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2011.

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin diseases that were reported in the Journal in 2011. Food allergy appears to be increasing in prevalence and carries a strong economic burden. Risk factors can include dietary ones, such as deficiency of vitamin D and timing of complementary foods, and genetic factors, such as filaggrin loss-of-function mutations.

Vaccines and immunomodulatory therapies for food allergy.

The apparent increase in food allergy prevalence has led to a surge in the amount of clinical and basic science research dedicated to the field. At the current time, allergen avoidance remains the cornerstone of treatment; however, recent clinical trials investigating various forms of immunotherapy have opened doors to the possible future application of an active treatment strategy in everyday practice. In addition, improvements in molecular biology have allowed researchers to purify, clone, and modify allergens, thus laying the groundwork for research on vaccines using modified proteins of decreased allergenicity.

Development and validation of educational materials for food allergy.

Objective: To develop and validate a food allergy educational program.

Study Design: Materials developed through focus groups and parental and expert review were submitted to 60 parents of newly referred children with a prior food allergy diagnosis and an epinephrine autoinjector. The main outcome was correct demonstration of an autoinjector.

Food allergy: mechanisms and therapeutics.

The immunologic mechanisms responsible for the development of allergic sensitization rather than tolerance to foods are not well understood, although there have been a number of recent advances in our understanding of why some foods are inherently allergenic. In addition, the involvement of alternative routes of exposure that are not inherently tolerogenic may play a role in sensitization to foods. Although there are no currently accepted therapeutic approaches to food allergy, there are a number of approaches to treatment in preclinical or clinical trials.

Quality of life in food allergy.

Purpose Of Review: The purpose of this review is to provide a review of studies examining health-related quality of life (HRQL) in food-allergic individuals, with an emphasis on publications since 2007.

Recent Findings: Over the past few years, an increasing number of studies have addressed the impact that food allergy has on HRQL. Many studies have used generic quality-of-life instruments to compare HRQL between food-allergic patients and healthy controls or between food-allergic patients and persons with other disease states.

Epidemiology of food allergy.

Adverse reactions to foods can occur for a variety of reasons, but a food allergy is caused by a specific immune response. Challenges to determine the prevalence of food allergy include misclassification, biased participation, lack of simple diagnostic tests, rapid evolution of disease, large numbers of potential triggers, and varied clinical phenotypes. Nonetheless, it is clear that this is a common disorder, with studies suggesting a cumulative prevalence of 3% to 6%, representing a significant impact on quality of life and costs.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2010.

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin disease that were reported in the Journal in 2010. Key epidemiologic observations include an apparent increase in peanut allergy, with more than 1% of children affected, and increasing evidence that early food allergen exposure, rather than avoidance, might improve allergy outcomes. Advances in food allergy diagnosis include improved insights into prognosis and estimation of severity through component-resolved diagnostics and characterization of IgE binding to specific epitopes.

The diagnosis of food allergy.

Background: Food allergy is increasingly common; however, there is a discrepancy between the large number of people who believe they or their children are affected and the actual number with true food allergies. It is therefore imperative that physicians evaluating patients with possible adverse reactions to foods understand the current modalities used to diagnose food allergies.

Methods: Simple tests including skin-prick testing (SPT) and serum food-specific IgE testing are the most commonly used diagnostic tests to evaluate for IgE-mediated food reactions.

Bullying among pediatric patients with food allergy.

Background: There are reports of children and teens with food allergy being harassed because of their food allergy, yet no study to date has attempted to characterize these occurrences.

Objectives: To determine the presence and characteristics of bullying, teasing, or harassment of food-allergic patients owing to their food allergies.

Methods: Questionnaires were completed by food-allergic teens and adults and by parents of food-allergic children.

Diagnosis of food allergy: epicutaneous skin tests, in vitro tests, and oral food challenge.

Food allergy is becoming an increasingly common diagnosis. Because of this increase in prevalence, it is imperative that physicians evaluating patients with possible adverse reactions to foods understand the currently available assays and how they should best be used to accurately diagnose the disease. Simple tests such as skin prick testing (SPT) and serum food-specific IgE testing are the most commonly used diagnostic tests to evaluate for IgE-mediated food reactions.

Identification of IgE sequential epitopes of lentil (Len c 1) by means of peptide microarray immunoassay.

Background: Lentils are often responsible for allergic reactions to legumes in Mediterranean children. Although the primary sequence of the major allergen Len c 1 is known, the location of the IgE-binding epitopes remains undefined.

Objective: We sought to identify IgE-binding epitopes of Len c 1 and relate epitope binding to clinical characteristics.

US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up.

Background: Allergy to peanuts and tree nuts (TNs) is the leading cause of fatal allergic reactions in the United States, and the prevalence appears to be increasing.

Objectives: We sought to determine the US prevalence of self-reported peanut, TN, and sesame allergy in 2008 and compare results with comparable surveys conducted in 1997 and 2002.

Methods: A nationwide, cross-sectional, random telephone survey for peanut and TN allergy was conducted with a previously used questionnaire, with additional questions about sesame.

Immunologic features of infants with milk or egg allergy enrolled in an observational study (Consortium of Food Allergy Research) of food allergy.

Background: Immune features of infants with food allergy have not been delineated.

Objectives: We sought to explore the basic mechanisms responsible for food allergy and identify biomarkers, such as skin prick test (SPT) responses, food-specific IgE levels, and mononuclear cell responses, in a cohort of infants with likely milk/egg allergy at increased risk of peanut allergy.

Methods: Infants aged 3 to 15 months were enrolled with a positive SPT response to milk or egg and either a corresponding convincing clinical history of allergy to milk or egg or moderate-to-severe atopic dermatitis.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2009.

This review highlights some of the research advances in anaphylaxis and hypersensitivity reactions to foods, drugs, and insects, as well as advances in allergic skin disease that were reported in the Journal in 2009. Among key epidemiologic observations, several westernized countries report that more than 1% of children have peanut allergy, and there is some evidence that environmental exposure to peanut is a risk factor. The role of regulatory T cells, complement, platelet-activating factor, and effector cells in the development and expression of food allergy were explored in several murine models and human studies.

Food allergy.

Adverse immune responses to foods affect approximately 5% of young children and 3% to 4% of adults in westernized countries and appear to have increased in prevalence. Food-induced allergic reactions are responsible for a variety of symptoms and disorders involving the skin and gastrointestinal and respiratory tracts and can be attributed to IgE-mediated and non-IgE-mediated (cellular) mechanisms. Genetic disposition and environmental factors might abrogate oral tolerance, leading to food allergy.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2008.

This review highlights some of the research advances in anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects and in allergic skin disease that were reported in the Journal in 2008. Key epidemiologic observations include a rise in anaphylaxis in a population-based study and lower rates of peanut allergy in Israel, where infants consume peanut early compared with the United Kingdom, where dietary introduction is generally delayed. Advances in food allergy diagnosis include IgE epitope mapping that discloses the likelihood and severity of allergy; studies correlating likelihood of clinical reactivity on the basis of food-specific IgE to sesame, peanut, milk, and tree nuts; and an observation that a low baseline angiotensin-converting enzyme level may be associated with having pharyngeal edema during a reaction.