Food allergy plays a significant pathogenic role among children with atopic dermatitis (AD).
The aims of this study were to evaluate allergy to egg in these children and determine the egg specific immunoglobulin E (IgE) cutoff point.
Design and Setting
It was a cross-sectional study that took place at Immunology, Asthma and Allergy Research Institute from 2005 to 2007.
Children younger than 14 years old with AD entered the study. Careful medical histories were taken and skin prick and Immuno-CAP tests with the most commonly offending foods (cow's milk, egg, wheat, peanut, and soy) were performed. Children with a clear, positive history of food allergy and a positive IgE-mediated test or those with positive responses to both IgE-mediated tests were determined to have food allergies. The egg-specific IgE level cutoff point was determined.
A hundred patients entered the study (from 2 months to 12 years old). They were divided into 3 age groups: first <2 years, second from 2 to <6 years, and third from 6 to 14 years. The most common food allergens were egg (39.22%) in the first, cow's milk (35.13%) and egg (32.43%) in the second, and peanut (25%) and egg (16.67%) in the third group. The egg-specific IgE cutoff point value was 0.62 kUA/L (kilounits of allergen-specific IgE per liter). The positive predictive value was 95%.
Prevalence of egg allergy is highly significant in patients with AD.To use egg-specific IgE level cutoff point, the patient population under study must be considered.
egg allergy; atopic dermatitis; food allergy; specific IgE cutoff point
Anaphylaxis is an acute, systemic, and potentially fatal allergic reaction. Many things can cause anaphylaxis potentially but some agents are more common like some foods (milk, egg, soy, wheat, peanut, tree nut, shellfish, and fish), insect stings, medications, latex, and food-dependent exercise-induced anaphylaxis. The goal of this study is to show the common causes of anaphylaxis among the children with anaphylaxis history who were referred to the Immunology, Asthma and Allergy Research Institute (IAARI) during a 4-year period (2005-2009).
Methods and Materials
During those 4 years, we registered all children (<14 years old) with a history of anaphylactic reaction. To prove the cause of anaphylaxis, we performed skin prick tests with suspected agents according to their history and measured specific IgE against them by the ImmunoCAP test. Recognition of common allergens was based on having a positive history for 1 allergen and positive skin prick test or specific IgE for that at the same time, or having positive results from both tests when the allergen was unclear. Idiopathic anaphylaxis was a reaction when any known allergen and positive tests were not obtained.
One hundred ninety-three nonfatal anaphylactic attacks among 63 children were recognized. In total, the most current cause of anaphylaxis in children was food (89.7%). Milk (49.3%) and wheat (26.1%) were the most common. Other foods were egg (8.7%), nuts (2.8%), and spices (2.8%). Six children (8.7%) were sensitive to multiple food allergens like milk, egg, and wheat. Five (7.1%) of 63 patients had anaphylactic attack because of stinging. Wasp was the trigger in 3 (4.3%) of them and honeybee was the cause in 1 (1.4%). The last one was because of unknown hymenoptera. There were 2 idiopathic cases of all 63 patients.
Food allergens, especially milk and wheat, are the most common cause of anaphylaxis in children. Because anaphylaxis can be fatal, it is advisable to recognize its causes in different communities to prevent recurrent attacks.
anaphylaxis; common causes; children
Food allergy primarily causes anaphylaxis in children. Food such as egg, cow milk, wheat and peanut are common allergen in Japan.
In this study total IgE, IgE RAST value and prick test are evaluated to monitor the efficacy outcome in wheat or hen's egg-allergy infants treated with slow specific oral tolerance induction (sSOTI) therapy.
The 3 infants suffered from IgE-mediated food allergy (wheat: 2 years 8 or 10 months old boy [threshold dose 25 g] and girl [0.7 g], hen's egg: 4 years 9 months old girl [1.8 g]), diagnosed, by food challenge, as allergy to wheat and egg. Then, the patients were treated with sSOTI either with hard-boiled egg or wheat noodle at home daily starting with 0.1 g, respectively, increased to a dose of 60 g egg or 100 g wheat, every one to 2 weeks in double dose of the weight, until tolerance was taken on. The daily maintenance dose was 10 g for each food. Four weeks later confirmed was evolution of tolerance by re-challenge. The safety and efficacy of the sSOTI therapy were confirmed in these infants. Total IgE levels were increased after SOTI therapy whereas IgE RAST value to causative antigen such as egg and wheat, contrastingly reduced. IgE RAST value to some other food as cow's milk, reduced coincidently by bystander inhibition. IgE RAST value to a food, negative in prick test, was increased again, whereas that to a food, positive in the test, was carried on.
The results indicates that sSOTI therapy induced causative antigen-specific IgE-mediated tolerance in children with wheat or egg allergy, and the set of total IgE increased, reduced IgE RAST value and positive prick test was of service to evaluate evolution of tolerance in slow SOTI therapy.
Beef allergies are relatively rare, especially in adults. However, clinical manifestations can vary from urticaria, angioedema, anaphylaxis to gastrointestinal symptoms. Currently available tests, such as skin testing or in vitro determination of beef-specific immunoglobulin E (IgE), do not provide an accurate diagnosis of beef allergy. The recent development of the basophil activation test (BAT) presents a new opportunity for the diagnosis of food allergies. Here, we report a 37-year-old woman with a history of recurrent generalised urticaria, nausea, vomiting and hypotension after ingestion of beef, suggesting a beef allergy. Although the skin prick test and serum specific IgE to beef, pork and milk allergens showed negative results using commercial kits, the BAT showed significant upregulation of CD203c in a dose-dependent manner compared to both non-atopic and atopic controls. To our knowledge, this is the first case study of beef allergy consisting of a non-IgE-mediated reaction. The detection of food allergies using direct basophil activation is suggested to complement conventional diagnostic tests.
Beef allergy; basophil activation test; CD203c, human
We present two cases of food and exercise-induced anaphylaxis (FEIA) in patients with a diagnosis of oral allergy syndrome (OAS) to the implicated foods. Patient A had FEIA attributed to fresh coriander and tomato and Patient B to fresh celery. These food allergens have been implicated in OAS and have structural antigenic similarity to that of birch and/or grass. Both patients’ allergies were confirmed by fresh skin prick tests. In both cases, strenuous exercise was antecedent to the systemic anaphylaxis reaction and subsequent ingestion without exercise produced only local symptoms of perioral pruritus. We review the current proposed mechanisms for food and exercise induced anaphylaxis to oral allergens and propose a novel and more biologically plausible mechanism. We hypothesize that the inhibitory effects of exercise on gastric acid secretion decreases the digestion of oral allergens and preserves structural integrity, thereby allowing continued systemic absorption of the allergen whether it be profilins, lipid transfer proteins, or other antigenic determinants.
Food and exercise-induced anaphylaxis; Food allergy; Exercise; Anaphylaxis; Mechanism
The evaluation of soy allergy in patients over 14 years of age suffering from atopic dermatitis. The evaluation of the correlation to the occurence of peanut and pollen allergy.
Materials and Methods:
Altogether 175 persons suffering from atopic dermatitis were included in the study: Specific IgE, skin prick tests, atopy patch tests to soy, history and food allergy to peanut and pollen allergy were evaluated.
The early allergic reaction to soy was recorded in 2.8% patients. Sensitization to soy was found in another 27.2% patients with no clinical manifestation after soy ingestion. The correlation between the positive results of examinations to soy and between the occurence of peanut and pollen allergy was confirmed in statistics.
Almost one third of patients suffering from atopic dermatitis are sensitized to soy without clinical symptoms. The early allergic reaction to soy occur in minority of patients suffering from atopic dermatitis.
Atopic dermatitis; pollen allergy; peanut allergy; soy allergy; specific IgE; skin prick tests
Wheat allergy is among the most common food allergy in children, but few publications are available assessing the risk of anaphylaxis due to wheat.
In this study, we report the case of near-fatal anaphylaxis to wheat in a patient undergoing an oral food challenge (OFC) after the ingestion of a low dose (256 mg) of wheat. Moreover, for the first time, we analyzed the risk of anaphylaxis during an OFC to wheat in 93 children, compared to other more commonly challenged foods such as milk, egg, peanuts, and soy in more than 1000 patients.
This study, which includes a large number of OFCs to wheat, shows that wheat is an independent risk factor that is associated with anaphylaxis requiring epinephrine administration (Odds Ratio [OR] = 2.4) and anaphylaxis requiring epinephrine administration to low dose antigen (OR = 8.02). Other risk factors for anaphylaxis, anaphylaxis requiring epinephrine administration, and anaphylaxis to low dose antigen was a history of a prior reaction not involving only the skin (OR = 1.8, 1.9 and 1.8 respectively). None of the clinical variables available prior to performing the OFC could predict which children among those undergoing OFCs to wheat would develop anaphylaxis or anaphylaxis for low dose antigen.
This study shows that wheat is an independent risk factor that is associated with anaphylaxis requiring epinephrine administration and anaphylaxis requiring epinephrine administration to low dose antigen.
Food-induced allergic reactions are responsible for a variety of symptoms and disorders involving the skin, gastrointestinal and respiratory tracts and can be attributed to IgE-mediated and non–IgE-mediated (cellular) mechanisms.
Food allergy frequency varies according to age, local diet, and many other factors. The diagnosis of food allergy is based on clinical history, skin prick test (SPT), food specific IgE and more recently atopy patch tests (APT). If needed the use of an oral food challenge to confirm allergy or tolerance.
Describes the case of a patient with multiple manifestations of food allergy after eating habit change.
Man 20 years with a history of food allergy to egg in childhood (at date in remission) asthma and rhinitis and urticaria in contact to cats. He presents an atopic dermatitis, recurrent abdominal pain and diarrhea 18 months after change in eating habits (he became vegetarian). He also presents oral syndrome with cow's milk. The patient had 4 episodes of anaphylaxis post prandial grade 3. In 3 of them the patient ate goat cheese and the other cow cheese. Also 2 of the episodes were associated with exercise. Skin prick tests with goat`s cheese: 13 mm, cow´s milk: 8 mm wheat: 3 mm, corn 3 mm, chicken 3.5 mm, egg yolk: 3.5 mm, avocado and rice 3 mm. Atopy patch test: (+ +) goat`s milk (+) peanuts and coffee. Total IgE 686 IU/mL.
Foods with positive results were excluded from the diet and a complete remission of atopic dermatitis, abdominal pain, diarrhea and anaphylaxis was observed. All foods were reintroduced successfully except milk of goats and cows milk. The patient is currently asymptomatic.
The literature describes different kinds of manifestations of food allergy: immediate hypersensitivity (IgE mediated), delayed hypersensitivity (T lymphocytes mediated) and mixed. Highlights in this case an adult patient with a history of atopy who makes changes in eating habits, developping a food allergy to goat´s and cow s milk, with immediate (anaphylaxis, oral syndrome) and delayed manifestations (atopic dermatitis and chronic diarrhea).
We examined the characteristics of food allergy prevalence and suggested the basis of dietary guidelines for patients with food allergies and atopic dermatitis. A total of 2,417 patients were enrolled in this study. Each subject underwent a skin prick test as well as serum immunoglobulin E (IgE) measurement. A double-blind, placebo-controlled food challenge was conducted using milk, eggs, wheat, and soybeans, and an oral food challenge was performed using beef, pork, and chicken. Food allergy prevalence was found among 50.7% in patients with atopic dermatitis. Among patients with food allergies (n = 1,225), the prevalence of non-IgE-mediated food allergies, IgE-mediated food allergies, and mixed allergies was discovered in 94.9%, 2.2%, and 2.9% of the patients, respectively. Food allergy prevalence, according to food item, was as follows: eggs = 21.6%, milk = 20.9%, wheat = 11.8%, soybeans = 11.7%, chicken = 11.7%, pork = 8.9% and beef = 9.2%. The total number of reactions to different food items in each patient was also variable at 45.1%, 30.6%, 15.3%, 5.8%, 2.2%, and 1.0% for 1 to 6 reactions, respectively. The most commonly seen combination in patients with two food allergies was eggs and milk. The clinical severity of the reactions observed in the challenge test, in the order of most to least severe, were wheat, beef, soybeans, milk, pork, eggs, and chicken. The minimum and maximum onset times of food allergy reactions were 0.2-24 hrs for wheat, 0.5-48 hrs for beef, 1.0-24 hrs for soybeans, 0.7-24 hrs for milk, 3.0-24 hrs for pork, 0.01-72 hrs for eggs, and 3.0-72 hrs for chicken. In our study, we examined the characteristics of seven popular foods. It will be necessary, however, to study a broader range of foods for the establishment of a dietary guideline. Our results suggest that it may be helpful to identify food allergies in order to improve symptoms in patients with atopic dermatitis.
Food allergy; atopic dermatitis; non-IgE-mediated allergy; IgE-mediated allergy
Data from many studies have suggested a rise in the prevalence of food allergies during the past 10 to 20 years. Currently, no curative treatments for food allergy exist, and there are no effective means of preventing the disease. Management of food allergy involves strict avoidance of the allergen in the patient's diet and treatment of symptoms as they arise. Because diagnosis and management of the disease can vary between clinical practice settings, the National Institute of Allergy and Infectious Diseases (NIAID) sponsored development of clinical guidelines for the diagnosis and management of food allergy. The guidelines establish consensus and consistency in definitions, diagnostic criteria, and management practices. They also provide concise recommendations on how to diagnose and manage food allergy and treat acute food allergy reactions. The original guidelines encompass practices relevant to patients of all ages, but food allergy presents unique and specific concerns for infants, children, and teenagers. To focus on those concerns, we describe here the guidelines most pertinent to the pediatric population.
food allergy; food hypersensitivity; infants; children; guidelines; anaphylaxis
The food labeling system for food allergens was introduced from April 2002 in Japan. To confirm the effectiveness of the system, we regularly conduct a nationwide food allergy survey every 3 years.
The survey was conducted in cooperation with over 1000 volunteer allergists in Japan at 2001, 2002, 2005 and 2008. We sent questionnaire to contributing doctors every 3 months based on the past survey system, and contributing doctors were asked to report immediate type food allergy cases seen by those doctors. In this survey, immediate type food allergy was defined as the patients who had developed symptoms due to food allergic reaction within 60 minutes after intake of offending food. The details of questionnaire consisted of age, sex, cause of food allergy, symptoms, CAP system, and type of onset.
A total of 8581 immediate type food allergy cases were reported by the doctors. The most common offending foods were hen's egg (39.0%), milk products (18.0%), wheat (9.4%), fruit (5.3%), crustacean (4.6%), peanuts (3.7%), fish egg, buckwheat and fish (3.6%). The most common clinical symptom was observed on skin (89.7%) followed by respiratory system (29.6%). Interestingly, the causes of food allergy were completely different from infancy (egg, milk, and wheat) to adulthood (wheat, crustacean and fruits). Anaphylactic shock was observed in 10.9% of the total reported cases. The cases of anaphylactic shock were due to hen's egg (27.1%), milk products (21.4%) and wheat (18.1%). Eleven percentages of patients had been hospitalized.
We revealed the current condition of the immediate type food allergy cases seen in Japan recent decade. Based on these data, countermeasures against food allergy are ongoing in collaboration with the Ministry of Health, Labour, and Welfare in Japan in order to improve quality of life of patients.
Immune features of infants with food allergy have not been delineated.
To explore basic mechanisms responsible for food allergy and identify biomarkers, e.g. prick skin tests (PST), food-specific IgE, and mononuclear cell responses in a cohort of infants with likely milk/egg allergy at increased risk of developing peanut allergy.
Infants aged 3–15 months were enrolled with a positive PST to milk or egg and either a corresponding convincing clinical history of allergy to milk or egg, or with moderate to severe atopic dermatitis (AD). Infants with known peanut allergy were excluded.
Overall, 512 infants (67% males) were studied with 308 (60%) having a history of a clinical reaction. Skin tests and/or detectable food-specific IgE revealed sensitization as follows: milk-78%, egg-89% and peanut-69%. PST and food-specific IgE levels were discrepant for peanut: 15% IgE ≥ 0.35 kUA/L/PST- versus 8% PST+/IgE < 0.35, p = 0.001. Mononuclear cell allergen stimulation screening for CD25, CISH, FOXP3, GATA3, IL-10, IL-4, IFN-gamma and TBET expression using casein, egg white and peanut revealed that only allergen-induced IL-4 expression was significantly increased in those with clinical allergy to milk (compared to non-allergic) and in those sensitized to peanut, despite the absence of an increase in GATA-3 mRNA expression.
Infants with likely milk/egg allergy are at considerably high risk of having elevated peanut-specific IgE (potential allergy). Peanut-specific serum IgE was a more sensitive indicator of sensitization than PST. Allergen-specific IL-4 expression may be a marker of allergic risk. Absence of an increase in GATA-3 mRNA expression suggests that allergen-specific IL-4 may not be of T cell origin.
food allergy; sensitization; atopy
The effect of food introduction timing on the development of food allergy remains controversial. We sought to examine whether the presence of childhood eczema changes the relationship between timing of food introduction and food allergy. The analysis includes 960 children recruited as part of a family-based food allergy cohort. Food allergy was determined by objective symptoms developing within 2 hours of ingestion, corroborated by skin prick testing/specific IgE. Physician diagnosis of eczema and timing of formula and solid food introduction were obtained by standardized interview. Cox Regression analysis provided hazard ratios for the development of food allergy for the same subgroups. Logistic regression models estimated the association of eczema and formula/food introduction with the risk of food allergy, individually and jointly. Of the 960 children, 411 (42.8%) were allergic to 1 or more foods and 391 (40.7%) had eczema. Children with eczema had a 8.4-fold higher risk of food allergy (OR, 95% CI: 8.4, 5.9–12.1). Among all children, later (>6 months) formula and rice/wheat cereal introduction lowered the risk of food allergy. In joint analysis, children without eczema who had later formula (OR, 95% CI: 0.5, 0.3–0.9) and later (>1 year) solid food (OR, 95% CI: 0.5, 0.3–0.95) introduction had a lower risk of food allergy. Among children with eczema, timing of food or formula introduction did not modify the risk of developing food allergy. Later food introduction was protective for food allergy in children without eczema but did not alter the risk of developing food allergy in children with eczema.
Even 70% patients allergic to pollens of plants are developing undesirable symptoms after eating foods of the plant origin. It is most often a result of the cross-allergy between these allergens. The aim of the study was to compare the group of patients with pollinosis with patients with pollinosis and food allergy.
Fifty eight patients at the age above 16 were included in the study. Patients were divided into 2 groups. Patients included in the first group were birch allergic without any symptoms after eating food (23 persons). Patients in the other group had birch pollen allergy and they had reported clinical symptoms after eating foods such as: apple, celery, carrot, tomato, banana, peach, peanut and hazelnut (35 persons). The skin prick tests with pollen and food allergens (commercial and native) and serum IgE concentration (total and specific) were determined for all individuals. The immunoblotting was performed for the patients with the positive value of birch, apple, celery and/or carrot specific IgE to confirm the cross-reactivity.
Patients with pollinosis and symptoms after eating plant foods were characterized by a significantly larger percentage of positive skin tests with the hazel allergen. In the first group patients revealed positive results of skin tests with food allergens, although they didn't reported the problem after consumption of them. No difference in total IgE levels was found between the 2 groups (271.5 ± 403.8 IU/mL vs 242.5 ± 340.9 IU/mL). Patients with birch allergy and hypersensitivity to food allergens showed significantly higher birch pollen specific IgE levels (11.8 ± 14.1 IU/mL vs 4.1 ± 6.6 IU/mL).
Sixty percent of all the patients with birch pollinosis reported manifestations symptoms after eating certain kind of food. These patients had most often clinical symptoms after eating apples, hazelnuts and of peaches, and less frequently symptoms after eating carrots, celery, peanuts, tomatoes and bananas. Although it seems that false positive results of skin tests with food allergens in the control group and the high level of the birch specific IgE might be the predictive factor of the allergy which may develop later; they require further studies.
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.
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.
Although much is known today about the prevalence of food allergy in the developed world, there are serious knowledge gaps about the prevalence rates of food allergy in developing countries. Food allergy affects up to 6% of children and 4% of adults. Symptoms include urticaria, gastrointestinal distress, failure to thrive, anaphylaxis and even death. There are over 170 foods known to provoke allergic reactions. Of these, the most common foods responsible for inducing 90% of reported allergic reactions are peanuts, milk, eggs, wheat, nuts (e.g., hazelnuts, walnuts, almonds, cashews, pecans, etc.), soybeans, fish, crustaceans and shellfish. Current assumptions are that prevalence rates are lower in developing countries and emerging economies such as China, Brazil and India which raises questions about potential health impacts should the assumptions not be supported by evidence. As the health and social burden of food allergy can be significant, national and international efforts focusing on food security, food safety, food quality and dietary diversity need to pay special attention to the role of food allergy in order to avoid marginalization of sub-populations in the community. More importantly, as the major food sources used in international food aid programs are frequently priority allergens (e.g., peanut, milk, eggs, soybean, fish, wheat), and due to the similarities between food allergy and some malnutrition symptoms, it will be increasingly important to understand and assess the interplay between food allergy and nutrition in order to protect and identify appropriate sources of foods for sensitized sub-populations especially in economically disadvantaged countries and communities.
Food allergy; Food hypersensitivity; Nutrition; Developing countries
To estimate the prevalence and clinical features of food allergy in children aged 0 to 2 years.
From January to February, 2009 and January to May, 2010, all well-infants and young children between the age of 0-2 years attending routine health visits at the Department of Primary Child Care, in Chongqing, Zhuhai and Hangzhou were invited to participate the study. Parents completed questionnaires and all children were skin prick tested to a panel of 10 foods (egg white, egg yolk, cow milk, soybean, peanut, wheat, fish, shrimp, orange and carrot). Based on the results of SPT and medical history, the subjects should undergo the suspected food elimination and oral food challenge under medical supervision. Food allergy was confirmed by the food challenge test.
There were 1,687 children recruited by the consent of their parents. Of 1,687 children approached, 1,604 (550 for Chongqing, 573 for Zhuhai and 481 for Hangzhou) fulfilled the study criteria for diagnosing food allergy. 100 children were confirmed to have challenge-proven food allergy in 3 cities (40 for Chongqing, 33 for Zhuhai and 27 for Hangzhou). The prevalence of food allergy in 0 to 2 years old children in Chongqing was 7.3%, in Zhuhai was 5.8% and in Hangzhou was 5.5%. There was no significant difference in the prevalence of food allergy in children under 2 years among the 3 cities, and the average prevalence for food allergy in children under 2 years was 6.2%. Egg was the most common allergen, followed by cow milk.
The prevalence of food allergy in 0 to 2 years old children in China was 5.5% to 7.3%. There was no significant difference in the prevalence of food allergy in children under 2 years among the 3 cities. Egg was the most common allergen, followed by cow milk.
Asia is a populous and diverse region and potentially an important source of information on food allergy. This review aims to summarize the current literature on food allergy from this region, comparing it with western populations. A PubMed search using strategies "Food allergy AND Asia", "Food anaphylaxis AND Asia", and "Food allergy AND each Asian country" was made. Overall, 53 articles, published between 2005 and 2012, mainly written in English were reviewed. The overall prevalence of food allergy in Asia is somewhat comparable to the West. However, the types of food allergy differ in order of relevance. Shellfish is the most common food allergen from Asia, in part due to the abundance of seafood in this region. It is unique as symptoms vary widely from oral symptoms to anaphylaxis for the same individual. Data suggest that house dust mite tropomysin may be a primary sensitizer. In contrast, peanut prevalence in Asia is extremely low compared to the West for reasons not yet understood. Among young children and infants, egg and cow's milk allergy are the two most common food allergies, with prevalence data comparable to western populations. Differences also exist within Asia. Wheat allergy, though uncommon in most Asian countries, is the most common cause of anaphylaxis in Japan and Korea, and is increasing in Thailand. Current food allergy data from Asia highlights important differences between East and West, and within the Asian region. Further work is needed to provide insight on the environmental risk factors accounting for these differences.
Food Allergy; Asia; West; Epidemiology; Prevalence; Shellfish
Food allergy is an emerging epidemic that affects all age groups, with the highest prevalence rates being reported amongst Western countries such as the United States (US), United Kingdom (UK), and Australia. The development of animal models to test various food allergies has been beneficial in allowing more rapid and extensive investigations into the mechanisms involved in the allergic pathway, such as predicting possible triggers as well as the testing of novel treatments for food allergy. Traditionally, small animal models have been used to characterise immunological pathways, providing the foundation for the development of numerous allergy models. Larger animals also merit consideration as models for food allergy as they are thought to more closely reflect the human allergic state due to their physiology and outbred nature. This paper will discuss the use of animal models for the investigation of the major food allergens; cow's milk, hen's egg, and peanut/other tree nuts, highlight the distinguishing features of each of these models, and provide an overview of how the results from these trials have improved our understanding of these specific allergens and food allergy in general.
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
Peanut allergy is the leading cause of food-related anaphylaxis and accidental exposures are common. Oral immunotherapy has been posited as a potential treatment.
Patients ages 3–65 with peanut-specific IgE ≥ 7 kU/L and/or a positive skin prick test with a history of an allergic reaction to peanut were recruited to undergo an oral immunotherapy protocol. All adverse reactions were recorded by research staff or patients in real time.
Twenty-four patients received 6662 doses. Symptoms have been mostly mild (84%) and only 3 severe gastrointestinal reactions required the administration of epinephrine. Abdominal pain has been the most common reaction, followed by oropharyngeal and lip pruritis. Respiratory symptoms have been rare.
In this trial of oral immunotherapy in adults and children, most reactions have been mild.
food allergy; oral immunotherapy; peanut allergy
Cow’s milk and hen’s egg are the most frequently encountered food allergens in the pediatric population. Skin prick testing (SPT) with commercial extracts followed by an oral food challenge (OFC) are routinely performed in the diagnostic investigation of these children. Recent evidence suggests that milk-allergic and/or egg-allergic individuals can often tolerate extensively heated (EH) forms of these foods. This study evaluated the predictive value of a negative SPT with EH milk or egg in determining whether a child would tolerate an OFC to the EH food product.
Charts from a single allergy clinic were reviewed for any patient with a negative SPT to EH milk or egg, prepared in the form of a muffin. Data collected included age, sex, symptoms of food allergy, co-morbidities and the success of the OFC to the muffin.
Fifty-eight patients had negative SPTs to the EH milk or egg in a muffin and underwent OFC to the appropriate EH food in the outpatient clinic. Fifty-five of these patients tolerated the OFC. The negative predictive value for the SPT with the EH food product was 94.8%.
SPT with EH milk or egg products was predictive of a successful OFC to the same food. Larger prospective studies are required to substantiate these findings.
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
The food hypersensitivity IgE-mediated in children is of 1.6% to 6%. It can be manifested clinically as allergy in different devices and systems. Skin prick tests have a positive predictive value of less than 50% and 95% of negative predictive value. Prick-to-Prick tests have not been studied extensively.
To clinically correlate food hypersensitivity to Prick and Prick-to-Prick tests in a group of children with allergy symptoms in the skin, the gastrointestinal tract and the respiratory system.
A retrospective study done in the department of Pediatric Allergy of a Children's Hospital from June 2008 to May 2011. Data was taken from the records of 100 patients who gave positive to Prick and Prick-to-Prick food tests. We also looked for the clinical setting referred to by the patient. The frequency and CI 95% were analyzed by Chi2. Out of the 100 patients, 48 were female and 52 male. These patients were grouped by age range. Fifteen patients fall within 1 to 2 years range, 15 patients fall within the 3 to 5 year range and 26 patients within the over-6-years range. Twenty patients presented asthma, 16 allergic rhinitis, 24 atopic dermatitis, 33 food allergy, 5 gastrointestinal eosinophilia, and 2 children presented other reactions. The tests were done with extracts of IPI ASAC Laboratories and fresh food. We considered that the tests that were positive were those with a wheal diameter greater than 3 mm over the negative control.
10%(95% CI, 4.12-15.88) of the patients had a reaction after the Prick test and presented clinical symptoms of which 30% were cutaneous and 70% gastrointestinal. Thirty six percent of the patients had a reaction after the Prick-to-Prick test (95% CI, 26.59-45.40)[P = 0.005] of which 17% developed respiratory symptoms, 22% skin, and 61% gastrointestinal. The main fresh foods with which the patients gave positive were: milk 16% (95% CI, 8.81-23.18), egg 10% (95% CI, 4.12-15.88), and wheat 7% (95% CI, 1.99-12.00). Prick tests like milk, eggs and corn could not be assessed properly by the sample size.
Prick-to-Prick tests are more effective than Prick to detect patients with food clinical reactions.