Food allergy: recent advances in pathophysiology and treatment.

Food allergies, defined as an adverse immune response to food proteins, affect as many as 6% of young children and 3%-4% of adults in westernized countries, and their prevalence appears to be rising. In addition to well-recognized acute allergic reactions and anaphylaxis triggered by IgE antibody-mediated immune responses to food proteins, there is an increasing recognition of cell-mediated disorders such as eosinophilic gastroenteropathies and food protein-induced enterocolitis syndrome. We are gaining an increasing understanding of the pathophysiology of food allergic disorders and are beginning to comprehend how these result from a failure to establish or maintain normal oral tolerance.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2007.

This review highlights some of the research advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects that were reported primarily in the Journal in 2007. Advances in diagnosis include possible biomarkers for anaphylaxis, improved understanding of the relevance of food-specific serum IgE tests, identification of possibly discriminatory T-cell responses for drug allergy, and an elucidation of irritant responses for vaccine allergy diagnostic skin tests. Mechanistic studies are discerning T-cell and cytokine responses central to eosinophilic gastroenteropathies and food allergy, including the identification of multiple potential therapeutic targets.

Peanut allergy: emerging concepts and approaches for an apparent epidemic.

Peanut allergy is typically lifelong, often severe, and potentially fatal. Because reactions can occur from small amounts, the allergy presents patients with significant obstacles to avoid allergic reactions. In North America and the United Kingdom, prevalence rates among schoolchildren are now in excess of 1%, framing an increasing public health concern and raising research questions about environmental, immunologic, and genetic factors that may influence outcomes of peanut allergy.

Food-allergy management from the perspective of restaurant and food establishment personnel.

Background: Restaurant and food establishment dining poses dangers for food-allergic consumers.

Objective: To identify, from the restaurant's perspective, factors that affect providing allergen-safe meals.

Methods: A structured questionnaire was administered to a convenience sample of restaurant personnel.

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

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 primarily in the Journal in 2006. Advances in diagnosis include identification of food proteins to which IgE binding is associated with severe reactions; elucidation of diagnostic relationships of skin prick test wheal size with outcomes of egg, tree nut, and sesame allergy; evaluation of the diagnostic utility of atopy patch testing for food; and the observation that yellow jacket sting outcomes are influenced by species. Mechanistic observations include the following: heating of birch pollen-related foods disrupts IgE binding but not T-cell epitopes; a simple imbalance of T(H)1/T(H)2 response does not explain variations in clinical expression of peanut allergy; and elucidation of the role of dendritic cells in drug hypersensitivity.

Peanut allergen exposure through saliva: assessment and interventions to reduce exposure.

Background: Exposure to food allergens through saliva (kissing, utensils) can cause local and systemic allergic reactions.

Objective: To determine the time course of peanut allergen (Ara h 1) persistence in saliva after ingestion of peanut butter and to evaluate mouth cleansing interventions to reduce salivary peanut allergen.

Methods: Thirty-eight individuals ingested 2 tablespoons of peanut butter, and saliva was collected at various time points.

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

This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin disease that were reported primarily in the Journal in 2005. Although studies documented deficiencies in community management of anaphylaxis, guidelines and National Institutes of Health summary reports provide direction toward improved research and education. At least 9% of young children "outgrow" a tree nut allergy.

Lack of association of HLA class II alleles with peanut allergy.

Background: Peanut allergy is a common and severe phenotype of food allergy with a strong genetic component; HLA class II polymorphisms are attractive candidate genes for this disorder.

Objective: To determine possible genotypic associations of HLA class II with peanut allergy and attempt replication of previously reported associations.

Methods: Sibling pairs discordant for peanut allergy were genotyped (low resolution) by polymerase chain reaction-based methods to 7 DQ and 18 DR allele groups.

Risk-taking and coping strategies of adolescents and young adults with food allergy.

Background: Fatal food-allergic reactions are most common among adolescents and young adults.

Objective: To gain insight toward devising interventions, we queried risk-taking behaviors and coping strategies of persons age 13 to 21 years with food allergy.

Methods: We used an Internet-based anonymous questionnaire devised on the basis of data from focus groups.

9. Food allergy.

Food allergy, defined as an adverse immune response to food proteins, affects as many as 6% of young children and 3% to 4% of adults. Food-induced allergic reactions are responsible for a variety of symptoms involving the skin, gastrointestinal tract, and respiratory tract and might be caused by IgE-mediated and non-IgE-mediated (cellular) mechanisms. Our understanding of how food allergy represents an abrogation of normal oral tolerance is evolving.

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

This review highlights some of the research advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects that were reported primarily in the Journal in 2004. Clinical observations included that gastrointestinal symptoms during anaphylaxis are associated with an increased risk for hypotension; recurrence of peanut allergy can occur for about 8% of children who pass an oral food challenge and is associated with continued avoidance of the food after the challenge; seafood allergy is reported by 2.3% of the US population; and determination of the time to resolution of childhood egg and milk allergy might be predictable by means of serial determination of food-specific IgE levels.

Food protein-induced enterocolitis syndrome: case presentations and management lessons.

Enterocolitis induced in infants by cow's milk and/or soy protein has been recognized for decades. Symptoms typically begin in the first month of life in association with failure to thrive and may progress to acidemia and shock. Symptoms resolve after the causal protein is removed from the diet but recur with a characteristic symptom pattern on re-exposure.

Development of a questionnaire to measure quality of life in families with a child with food allergy.

Background: Food allergy is potentially severe, affects approximately 5% of children, and requires numerous measures for food avoidance to maintain health. The effect of this disease on health-related quality of life (HRQL) has been documented by using generic instruments, but no disease-specific instrument is available.

Objective: To create a validated, food allergy-specific HRQL instrument to measure parental burden associated with having a child with food allergy: the Food Allergy Quality of Life-Parental Burden questionnaire.

Prevalence of seafood allergy in the United States determined by a random telephone survey.

Background: Seafood allergy is potentially severe, but the prevalence of this group of food allergies in the US population has not been determined.

Objective: To estimate the prevalence of seafood (fish, shellfish) allergy in the United States.

Methods: We performed a nationwide, cross-sectional, random telephone survey by using a standardized questionnaire.

Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insect stings.

This review highlights some of the research advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insect venom that were reported primarily in the Journal of Allergy and Clinical Immunology from 2002 through 2003. Among the topics highlighted are new insights into the pathogenesis of atopic dermatitis and potential strategies for more effective treatment of the atopic march. Patients should remain supine with raised legs during anaphylactic shock because upper body elevation could result in sudden death from loss of venous return to the heart.

Future approaches to food allergy.

Food allergy affects approximately 2% of the general US population, and its prevalence seems to be increasing. Despite the potential for a fatal outcome, no definitive therapies are available for food allergy. This article reviews novel approaches for the diagnosis and treatment of food allergy.

Nutritional management of pediatric food hypersensitivity.

The diagnosis and management of food allergy requires attention to several important dietary issues. Successful exclusion of identified dietary allergens requires extensive education regarding the interpretation of ingredient labels of commercial products and an appreciation for issues of cross-contact in settings such as restaurants and commercial manufacturing. Once a food or food group is eliminated, attention must be focused on potential dietary insufficiencies resulting from these exclusions.

Clinical aspects of gastrointestinal food allergy in childhood.

Gastrointestinal food allergies are a spectrum of disorders that result from adverse immune responses to dietary antigens. The named disorders include immediate gastrointestinal hypersensitivity (anaphylaxis), oral allergy syndrome, allergic eosinophilic esophagitis, gastritis, and gastroenterocolitis; dietary protein enterocolitis, proctitis, and enteropathy; and celiac disease. Additional disorders sometimes attributed to food allergy include colic, gastroesophageal reflux, and constipation.

Anaphylaxis and emergency treatment.

Food anaphylaxis is now the leading known cause of anaphylactic reactions treated in emergency departments in the United States. It is estimated that there are 30 000 anaphylactic reactions to foods treated in emergency departments and 150 to 200 deaths each year. Peanuts, tree nuts, fish, and shellfish account for most severe food anaphylactic reactions.

Food allergy.

Food allergy encompasses a range of disorders that result from adverse immune responses to dietary antigens. This group of conditions includes acute, potentially fatal reactions, and a host of chronic diseases that mainly affect the skin and gastrointestinal tract. Tools for diagnosis and management have not changed much in the past two decades, and include the clinical history, physical examination, tests for specific IgE antibody to suspected foods, elimination diets, oral food challenges, and provision of medications such as epinephrine for emergency treatment.

Clinical update on peanut allergy.

Background: Peanut allergy is common, potentially severe, and there has been a recent surge in clinical investigation of this important food allergen.

Objective: To provide the reader with a clinically oriented update on peanut allergy.

Data Sources: English language articles were selected from PubMed searches (search terms: peanut allergy, food allergy, anaphylaxis) and selected abstracts with a bias toward recent (3 years) studies judged to have immediate, practical clinical implications.

Clinical implications of cross-reactive food allergens.

As a consequence of the general increase in allergic sensitization, the prevalence of hypersensitivity reactions to multiple foods that share homologous proteins has become a significant clinical problem. A variety of these allergens conserved among plants (eg, profilin and lipid transfer proteins) and animals (eg, tropomyosin and caseins) have been characterized. Although studies with molecular biologic techniques have elucidated the nature of these ubiquitous allergens, clinical studies have lagged behind.

A voluntary registry for peanut and tree nut allergy: characteristics of the first 5149 registrants.

Background: A voluntary registry of individuals with peanut and/or tree nut allergy was established in 1997 to learn more about these food allergies.

Objective: The purpose of this study was to elucidate a variety of features of peanut and tree nut allergy among the first 5149 registry participants.

Methods: The registry was established through use of a structured questionnaire distributed to all members of the Food Allergy and Anaphylaxis Network and to patients by allergists.