A diagnosis of food allergies should be made based on the observation of allergic symptoms following the intake of suspected foods and the presence of allergen-specific IgE antibodies. The oral food challenge (OFC) test is the most reliable clinical procedure for diagnosing food allergies. Specific IgE testing of allergen components as well as classical crude allergen extracts helps to make a more specific diagnosis of food allergies. The Japanese Society of Pediatric Allergy and Clinical Immunology issued the 'Japanese Pediatric Guideline for Food Allergy 2012' to provide information regarding the standardized diagnosis and management of food allergies. This review summarizes recent progress in the diagnosis of food allergies, focusing on the use of specific IgE tests and the OFC procedure in accordance with the Japanese guidelines.
Food hypersensitivity; Immunoglobulin E; Oral food challenge
Food allergy is an important public health problem affecting 5% of infants and children in Korea. Food allergy is defined as an immune response triggered by food proteins. Food allergy is highly associated with atopic dermatitis and is one of the most common triggers of potentially fatal anaphylaxis in the community. Sensitization to food allergens can occur in the gastrointestinal tract (class 1 food allergy) or as a consequence of cross reactivity to structurally homologous inhalant allergens (class 2 food allergy). Allergenicity of food is largely determined by structural aspects, including cross-reactivity and reduced or enhanced allergenicity with cooking that convey allergenic characteristics to food. Management of food allergy currently focuses on dietary avoidance of the offending foods, prompt recognition and treatment of allergic reactions, and nutritional support. This review includes definitions and examines the prevalence and management of food allergies and the characteristics of food allergens.
Food allergy; Allergens; Cross reactions; Disease management
Food allergy is being increasingly recognised with the highest prevalence being in preschool children. Pathogenesis varies so diagnosis rests on careful history and clinical examination, appropriate use of skin prick and serum-specific IgE testing, food challenge, and supervised elimination diets. A double blind placebo controlled food challenge is the gold standard diagnostic test. Avoidance of the allergenic food is the key towards successful management. IgE mediated food allergy may present as a potentially fatal anaphylactic reaction, and management consists of the appropriate use of adrenaline (epinephrine) and supportive measures. Sensitisation remains a key target for intervention. Disease modifying agents are currently under trial for managing difficult allergies. Management requires a multidisciplinary approach and follow up.
Food allergy is defined as an adverse immunologic response to a dietary protein. Food-related reactions are associated with a broad array of signs and symptoms that may involve many bodily systems including the skin, gastrointestinal and respiratory tracts, and cardiovascular system. Food allergy is a leading cause of anaphylaxis and, therefore, referral to an allergist for appropriate and timely diagnosis and treatment is imperative. Diagnosis involves a careful history and diagnostic tests, such as skin prick testing, serum-specific immunoglobulin E (IgE) testing and, if indicated, oral food challenges. Once the diagnosis of food allergy is confirmed, strict elimination of the offending food allergen from the diet is generally necessary. For patients with significant systemic symptoms, the treatment of choice is epinephrine administered by intramuscular injection into the lateral thigh. Although most children “outgrow” allergies to milk, egg, soy and wheat, allergies to peanut, tree nuts, fish and shellfish are often lifelong. This article provides an overview of the epidemiology, pathophysiology, diagnosis, management and prognosis of patients with food allergy.
Food allergies affect 6% of children and 3% to 4% of adults in the United States. Although several studies have examined the prevalence of food allergy, little information is available regarding the prevalence of multiple food allergies. Estimates of prevalence of people allergic to multiple foods is difficult to ascertain because those with allergy to one food may avoid additional foods for concerns related to cross-reactivity, positive tests, or prior reactions, or they may be reluctant to introduce foods known to be common allergens. Diagnosis relies on an accurate history and selective IgE testing. It is important to understand the limitations of the available tests and the role of cross-reactivity between allergens. Allergen avoidance and readily accessible emergency medications are the cornerstones of management. In addition, a multidisciplinary approach to management of individuals with multiple food allergies may be needed, as avoidance of several food groups can have nutritional, developmental, and psychosocial consequences.
Multiple food allergy; IgE; Sensitization; Cross-reactivity; Diagnosis; Allergy management
The European Academy of Allergy and Clinical Immunology is in the process of
developing its Guideline for Food Allergy and Anaphylaxis, and this protocol
of a systematic review is one of seven inter-linked evidence syntheses that
are being undertaken in order to provide a state-of-the-art synopsis of the
current evidence base in relation to epidemiology, prevention, diagnosis and
clinical management and impact on quality of life, which will be used to
inform the formulation of clinical recommendations.
The aims of the systematic review will be to understand and describe the
epidemiology of food allergy, i.e. frequency, risk factors and outcomes of
patients suffering from food allergy, and to describe how these
characteristics vary by person, place and time.
A highly sensitive search strategy has been developed to retrieve articles
that have investigated the various aspects of the epidemiology of food
allergy. The search will be implemented by combining the concepts of food
allergy and its epidemiology from electronic bibliographic databases.
This systematic review will provide the most up to date estimates of the
frequency of food allergy in Europe. We will attempt to break these down by
age and geographical region in Europe. Our analysis will take into account
the suitability of the study design and the respective study biases that
could affect exposure and outcome. We will examine the different methods to
diagnose food allergy and the associated measures of occurrence.
Food allergy; IgE-mediated; Risk; Anaphylaxis; Epidemiology; Prevalence; Incidence
Prevalence of allergic diseases is increasing worldwide, including food allergy. It is different between countries because food allergy can vary by culture and population. Prevalence of food allergy in Indonesia is unknown; therefore it is not known yet the burden and impact of food allergy in our population. However, we already start to formulate guidelines for diagnosis and management of food allergy, especially cow's milk allergy.
Food allergy; Cow's milk allergy; Indonesia
The literature on diagnostic tests for food allergy currently lacks clear consensus regarding the accuracy and safety of different investigative approaches. The European Academy of Allergy and Clinical Immunology is in the process of developing its Guideline for Food Allergy and Anaphylaxis, and this systematic review is one of seven inter-linked evidence syntheses that are being undertaken in order to provide a state-of-the-art synopsis of the current evidence base in relation to epidemiology, prevention, diagnosis and clinical management, and impact on quality of life, which will be used to inform the formulation of clinical recommendations. The aim of this systematic review will be to assess the diagnostic accuracy of tests aimed at supporting the clinical diagnosis of IgE-mediated food allergy.
The following databases from inception to September 30, 2012 will be searched for studies of diagnostic tests: Cochrane Library (Wiley&Sons); MEDLINE (OVID); Embase (OVID); CINAHL (Ebscohost); ISI Web of Science (Thomson Web of Knowledge); TRIP Database (web http://www.tripdatabase.com); and Clinicaltrials.gov (NIH web). These database searches will be supplemented by contacting an international panel of experts. Studies evaluating APT, SPT, specific-IgE, and component specific-IgE in participants of any age with suspected food allergy will be included. The reference standard will be DBPCFC in at least 50% of the participants. Studies will be quality assessed by using the QUADAS-2 instrument. We will report summary statistics such as sensitivity, specificity, and/or likelihood ratios. We will use the hierarchical summary ROC (HSROC) model to summarize the accuracy of each test and to compare the accuracy of two or more tests.
Decisions on which tests to use need to be guided by availability of tests, populations being cared for, risks, financial considerations and test properties. This review will examine papers from around the world, covering children and adults with suspected food allergy in varying populations and concentrated on four type of tests: APT, SPT, specific-IgEs, and component specific-IgEs.
Food allergy; IgE-mediated; Diagnosis; Diagnostic tests
Many common foods including cow's milk, hen's egg, soya, peanut, tree nuts, fish, shellfish, and wheat may cause food allergies. The prevalence of these immune-mediated adverse reactions to foods ranges from 0.5% to 9% in different populations. In simple terms, the cornerstone of managing food allergy is to avoid consumption of foods causing symptoms and to replace them with nutritionally equivalent foods. If poorly managed, food allergy impairs quality of life more than necessary, affects normal growth in children, and causes an additional economic burden to society. Delay in diagnosis may be a further incremental factor. Thus, an increased awareness of the appropriate procedures for both diagnosis and management is of importance. This paper sets out to present principles for taking an allergy-focused diet history as part of the diagnostic work-up of food allergy. A short overview of guidelines and principles for dietary management of food allergy is discussed focusing on the nutritional management of food allergies and the particular role of the dietitian in this process.
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.
Child; Food; Allergy; Diagnosis
Respiratory allergy and allergy to foods continue to be important health issues. There is evidence to indicate that the incidence of food allergy around the world is on the rise. Current estimates indicate that approximately 5% of young children and 1-2% of adults suffer from true food allergy (Kagan 2003). Although a large number of in vivo and in vitro tests exist for the clinical diagnosis of allergy in humans, we lack validated animal models of allergenicity. This deficiency creates serious problems for regulatory agencies and industries that must define the potential allergenicity of foods before marketing. The emergence of several biotechnologically derived foods and industrial proteins, as well as their potential to sensitize genetically predisposed populations to develop allergy, has prompted health officials and regulatory agencies around the world to seek approaches and methodologies to screen novel proteins for allergenicity.
Skin prick tests are the first investigation in allergy diagnostics and their use is described in all the guidelines on atopic eczema. However, the clinical usefulness of skin prick tests is the subject of great debate. On the one hand, skin prick tests allow the identification both of individuals at risk for food allergy and of the allergen inducing the eczematous flare. On the other hand, when performed by a non-specific specialist, positive skin prick tests to foods may wrongly lead to prolonged elimination diets, which may induce nutritional deficiencies and perhaps loss of tolerance to the avoided foods. Furthermore, skin prick tests increase health costs. A consensus on this topic has not yet been reached. Considering the diversity of clinical stages in which it occurs, atopic eczema presentation should be the starting point to determine whether or not skin prick tests should be carried out.
Atopic dermatitis; Atopic eczema; Skin prick test; Food allergy
We present 17 children from 11 families with the allergic form of Meadow's syndrome. In all cases their mothers believed that they had severe disease due to allergies--in 16 cases to foods and in one to house dust mite. The maternal obsession with allergen avoidance resulted in bizarre diets and life styles. Most mothers were articulate and middle class, and many had marital problems (three single parents). They had a limpet-like attachment to their child and insisted on many medical consultations. Management proved very difficult and despite careful exclusion of allergic disease, many remained on diets and failed allergy clinic follow up. In most cases the obsession with allergy had been initiated by doctors.
Cow's milk is the most common food allergen in infants and the diagnosis of cow's milk allergy is difficult, even with the use of several diagnostic tests. Therefore, elimination diets and challenge tests are essential for the diagnosis and treatment of this disorder. The aim of this study is to report the clinical presentation and nutritional status of children evaluated by pediatric gastroenterologists for the assessment of symptoms suggestive of cow's milk allergy.
An observational cross-sectional study was performed among 9,478 patients evaluated by 30 pediatric gastroenterologists for 40 days in 5 different geographical regions in Brazil. Clinical data were collected from patients with symptoms suggestive of cow's milk allergy. The nutritional status of infants (age ≤ 24 months) seen for the first time was evaluated according to z-scores for weight-for-age, weight-for-height, and height-for-age. Epi-Info (CDC-NCHS, 2000) software was used to calculate z-scores.
The prevalence of suspected cow's milk allergy in the study population was 5.4% (513/9,478), and the incidence was 2.2% (211/9,478). Among 159 infants seen at first evaluation, 15.1% presented with a low weight-for-age z score (< -2.0 standard deviation - SD), 8.7% with a low weight-for-height z score (< -2.0 SD), and 23.9% with a low height-for-age z score (< -2.0 SD).
The high prevalence of nutritional deficits among infants with symptoms suggestive of cow's milk allergy indicates that effective elimination diets should be prescribed to control allergy symptoms and to prevent or treat malnutrition.
Over the past 20 years, food allergy has become an increasingly prevalent international health problem primarily in developed countries. An explanation for this increased prevalence is currently under investigation as it is not well understood. Allergic reactions can result in life threatening anaphylaxis over a short period of time, so the current standard of care dictates strict avoidance of suspected trigger foods and accessibility to injectable epinephrine. Intervention at the time of exposure is considered a rescue therapy rather than a disease modifying treatment. In recent years, investigators have been studying allergen immunotherapy as a way to promote induction of oral tolerance. These efforts have shown some promise towards a viable disease modifying therapy for food allergies. This review will examine the mechanisms of oral tolerance and the breakdown that leads to food allergy, as well as the history and current state of oral and sublingual immunotherapy development.
food allergy; oral tolerance; oral immunotherapy; sublingual immunotherapy
Food allergy is a serious medical problem without definitive treatment at this time. Intense research focuses on severe peanut allergy. Recombinant peanut major allergens engineered to lose IgE binding capacity mixed with E coli showed great promise in a murine model of peanut anaphylaxis. Rectal vaccine containing E.coli expressing engineered recombinant major peanut allergens Ara h 1, 2, 3 is in preparation for first human clinical trials. Oral desensitization and sublingual immunotherapy with food extracts represent another approach that is being actively explored. Novel therapies must be carefully evaluated in respect to safety and long-lasting effect on oral food tolerance before being applied in clinical practice. Diversity of approaches and promising preliminary results bring hope for patients with food allergy.
Food allergy; peanut allergy; immunotherapy; oral desensitization; sublingual immunotherapy; recombinant engineered allergens; recombinant engineered food proteins; food allergy therapy
The European Academy of Allergy and Clinical Immunology is developing guidelines about how to prevent and manage food allergy. As part of the guidelines development process, a systematic review is planned to examine published research about the prevention of food allergy. This systematic review is one of seven inter-linked evidence syntheses that are being undertaken in order to provide a state-of-the-art synopsis of the current evidence base in relation to epidemiology, prevention, diagnosis and clinical management, and impact on quality of life, which will be used to inform clinical recommendations. The aim of this systematic review will be to assess the effectiveness of approaches for the primary prevention of food allergy.
Seven bibliographic databases will be searched from their inception to September 30, 2012 for systematic reviews, randomized controlled trials, quasi-randomized controlled trials, controlled clinical trials, controlled before-and-after studies, interrupted time series and cohort studies. Cohort studies will be included due to an inability to randomize with interventions such as breastfeeding. Studies that focused on the development of either food sensitization (a proxy measure) or food allergy will also be eligible for inclusion. Studies will be critically appraised using the Critical Appraisal Skills Program and Cochrane Risk of Bias tools, as appropriate.
There is a lack of rigorous evidence to support recommendations about how to prevent the development of food allergy. It would appear that it is important to see the prevention of food allergy in the context of individual, family and wider factors that may influence its development. There is much left to learn about preventing food allergy, and this is a priority given the high societal and healthcare costs involved. This systematic review will help to further this learning.
Food allergy; lLgE-mediated; Prevention
The aim of this study is to clarify the cross section of pediatric food allergy patients. We investigated the profiles of food allergy (FA) patients seen in our department.
The number of food allergy patients seen in our department from January to December in 2010 was a total of 1,822 (male: 1207, female: 615, mean age: 5.8 ± 3.8 year). We collected and analyzed the clinical information of these patients from our medical record. We obtained information on the age of FA onset & FA diagnosis, clinical types of FA at the onset, causative food allergens, other allergic complications, and application of oral immunotherapy (OIT).
The average age of FA onset was 8 months, and that of diagnosis was 1 year old, respectively. The most common clinical types of FA at the time of onset were infantile atopic dermatitis (AD) type with food allergy (66.4%) followed by immediate type (30.8%). Food allergens avoided by the patients were the total number of 4,203 items (2.1 items as average). The most common eliminated food was hen's egg (1,245 cases; 29.6%), followed by cow's milk (786 cases; 18.7%), peanut (449 cases; 10.7%), and wheat (407 cases; 9.7%). Food-dependent exercise-induced anaphylaxis (FDEIA) was the total of 18 cases, and the most common causative food for FDEIA was wheat (10 cases) followed by peach (4 cases). One hundred and seventy five cases (9.6%) were currently receiving OIT. Main causative foods under OIT were hen's egg (63 cases), cow's milk (80 cases), and wheat (30 cases). The average starting age of OIT was 7.1 years old. Regarding complications of allergic diseases other than FA, 1119 (61.4%) had atopic dermatitis, and 541 (29.7%) bronchial asthma.
We were able to clarify the cross section of food allergy patients in our department and to obtain the basic data to follow continuous transition of these patients.
Dietary considerations play an important role in the diagnosis, treatment and management of immunologic and nonimmunologic reactions to foods. Food diaries and trial elimination diets may prove helpful in identifying the responsible foods. Elimination diets must be monitored carefully for nutritional adequacy and should be used no longer than absolutely necessary; in some instances appropriate vitamin and mineral supplementation may be necessary. Ideally the identification of foods that provoke symptoms should be confirmed by means of double-blind challenge testing. Avoidance of some problem foods is unlikely to cause nutritional problems, but the practical and nutritional implications of allergies to staple foods such as cow's milk, eggs and wheat are far greater. Nonimmunologic adverse reactions that may mimic food allergic reactions include gastrointestinal disorders, sensitivity to food additives and psychologically based adverse reactions. There may be some degree of tolerance in metabolic disorders, which makes dietary management easier. Sensitivity to food additives necessitates careful scrutiny of food labels. In psychologic adverse reactions to foods, several foods are often involved, which increases the risk of nutritional problems.
The European Academy of Allergy and Clinical Immunology is in the process of developing its Guideline for Food Allergy and Anaphylaxis, and this systematic review is one of seven inter-linked evidence syntheses that are being undertaken in order to provide a state-of-the-art synopsis of the current evidence base in relation to epidemiology, prevention, diagnosis and clinical management, and impact on quality of life, which will be used to inform clinical recommendations. The aim of this systematic review will be to determine which validated instruments can be employed to enable assessment of the impact of, and investigations and interventions for, food allergy on health-related quality of life.
Seven bibliographic databases were searched from their inception to September 30, 2012 for disease-specific HRQL questionnaires that were specifically designed for use with patients/carers and any articles relating to the description, development and/or the validation of the above identified HRQLs. There were no language or geographic restrictions. We will assess the development of the instruments identified and their performance properties including: validity; generalizability; responsiveness; managing missing data; how variation in patient demography was managed; and cross-cultural and linguistic adaptation, using a previously reported quality assessment tool.
Using appropriately developed and validated instruments is critical to the accurate evaluation of HRQL in people with food allergy. This review will systematically appraise the evidence on the subject and help to identify any gaps.
Food allergy; IgE-mediated; QOL; Quality of life
Food allergy prevalence is increasing in US children. Presently, the primary means of preventing potentially fatal reactions are avoidance of allergens, prompt recognition of food allergy reactions, and knowledge about food allergy reaction treatments. Focus groups were held as a preliminary step in the development of validated survey instruments to assess food allergy knowledge, attitudes, and beliefs of parents, physicians, and the general public.
Eight focus groups were conducted between January and July of 2006 in the Chicago area with parents of children with food allergy (3 groups), physicians (3 groups), and the general public (2 groups). A constant comparative method was used to identify the emerging themes which were then grouped into key domains of food allergy knowledge, attitudes, and beliefs.
Parents of children with food allergy had solid fundamental knowledge but had concerns about primary care physicians' knowledge of food allergy, diagnostic approaches, and treatment practices. The considerable impact of children's food allergies on familial quality of life was articulated. Physicians had good basic knowledge of food allergy but differed in their approach to diagnosis and advice about starting solids and breastfeeding. The general public had wide variation in knowledge about food allergy with many misconceptions of key concepts related to prevalence, definition, and triggers of food allergy.
Appreciable food allergy knowledge gaps exist, especially among physicians and the general public. The quality of life for children with food allergy and their families is significantly affected.
Food allergy poses a significant burden on patients, families, health care providers, and the medical system. The increased prevalence of food allergy has brought about investigation as to its cause and new treatments. Currently, the only treatment available is to avoid the food and symptomatically treat any reactions. There are multiple clinical and murine models of food allergy treatment that use allergen specific and nonspecific pathways. Allergen specific treatments use mucosal antigen exposure as a method of inducing desensitization and tolerance. Allergen nonspecific methods act via a more global TH2 suppressive mechanism and may be useful for those patients with multiple food allergies.
food hypersensitivity; treatment; immunotherapy
The UK NICE guideline on the Diagnosis and Assessment of Food Allergy in Children and Young People was published in 2011, highlighting the important role of primary care physicians, dietitians, nurses and other community based health care professionals in the diagnosis and assessment of IgE and non-IgE-mediated food allergies in children. The guideline suggests that those with suspected IgE-mediated disease and those suspected to suffer from severe non-IgE-mediated disease are referred on to secondary or tertiary level care. What is evident from this guideline is that the responsibility for the diagnostic food challenge, ongoing management and determining of tolerance to cow’s milk in children with less severe non-IgE-mediated food allergies is ultimately that of the primary care/community based health care staff, but this discussion fell outside of the current NICE guideline. Some clinical members of the guideline development group (CV, JW, ATF, TB) therefore felt that there was a particular need to extend this into a more practical guideline for cow’s milk allergy. This subset of the guideline development group with the additional expertise of a paediatric gastroenterologist (NS) therefore aimed to produce a UK Primary Care Guideline for the initial clinical recognition of all forms of cow’s milk allergy and the ongoing management of those with non-severe non-IgE-mediated cow’s milk allergy in the form of algorithms. These algorithms will be discussed in this review paper, drawing on guidance primarily from the UK NICE guideline, but also from the DRACMA guidelines, ESPGHAN guidelines, Australian guidelines and the US NIAID guidelines.
Cow’s milk allergy; Primary care; Food allergy; Diagnosis; Management; Hypoallergenic formula
Food allergy affects 3.9% of US children and is increasing in prevalence. The current standard of care involves avoidance of the triggering food and treatment for accidental ingestions. While there is no current curative treatment, there are a number of therapeutic strategies under investigation. Allergen specific therapies include oral and sublingual immunotherapy with native food protein as well as recombinant food proteins. Allergen non-specific therapies include a Chinese herbal formula (FAHF-2) and the use of anti-IgE monoclonal antibody therapy. Although none of these treatments are ready for clinical use, these therapeutic strategies present promising options for the future of food allergy.
anaphylaxis; desensitization; food allergy; oral immunotherapy; subcutaneous immunotherapy; sublingual immunotherapy; tolerance
Six randomized clinical trials have been implemented to examine the efficacy of tenofovir disoproxil fumarate (TDF) and/or TDF/emtricitabine (TDF/FTC) as preexposure prophylaxis for HIV-1 infection (PrEP). Although largely complementary, the six trials have many similar features. As the earliest results become available, an urgent question may arise regarding whether changes should be made in the conduct of the other trials. To consider this in advance, a Consultation on the Implications of HIV Pre-Exposure Prophylaxis (PrEP) Trials Results sponsored by the Division of AIDS (DAIDS) of the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), and the Bill and Melinda Gates Foundation (BMGF) was held on January 29, 2010, at the Natcher Conference Center, NIH, Bethesda, MD. Participants included basic scientists, clinical researchers (including investigators performing the current PrEP trials), and representatives from the U.S. Food and Drug Administration (FDA) and the agencies sponsoring the trials: the U.S. Centers for Disease Control and Prevention (CDC), the U.S. Agency for International Development (USAID), the BMGF, and the U.S. NIH. We report here a summary of the presentations and highlights of salient discussion topics from this workshop.