Prevalence of Immediate-Type Food Allergy in Korean Schoolchildren in 2015: A Nationwide, Population-based Study

Buckwheat Allergy in Asia

PURPOSE OF REVIEW

Buckwheat (BW) allergy is a significant issue in Asia. This review delves into three types of BW allergy: immediate food allergy; food-dependent, exercise-induced anaphylaxis (FDEIA) as a subset of immediate food allergy; and food protein-induced enterocolitis syndrome (FPIES); by comparing data from Asian and non-Asian countries.

RECENT FINDINGS

Most studies on BW have been published in Japan and Korea, and only a few studies on the topic have been done outside Asia. To date, seven components of common BW (Fagopyrum esculentum) and four components of Tartary BW (Fagopyrum tartaricum) have been implicated in BW allergy. Although BW-sIgE has limited utility for evaluating immediate BW allergy, Fag e 3-specific IgE, one of the components of common BW, and the skin prick test are diagnostically useful. The present review aims to shed light on the current state of knowledge, highlight research gaps, and suggest future directions in the management and understanding of BW allergy.

Predicting the Outcome of Pediatric Oral Food Challenges for Determining Tolerance Development

PURPOSE

Despite the risk of anaphylaxis, oral food challenges (OFCs) are performed clinically for various indications, particularly to confirm tolerance development. This study aimed to assess OFCs by relevant indications and build an outcome prediction model to help determine when to perform OFCs in children who are likely to have developed immune tolerance.

METHODS

In total, 432 pediatric OFCs were retrospectively analyzed according to indications. Clinical characteristics, serum total immunoglobulin (Ig) E, blood eosinophils, and specific IgE and IgG4 levels for food allergens were noted and compared. Machine learning was utilized to select the most important variables in determining the passage of the OFCs, and prediction models were constructed using the selected variables.

RESULTS

OFCs were most commonly performed to confirm tolerance development (number, %; 267, 61.8%). The most common food allergens tested were egg (191, 44.2%) and milk (135, 31.3%). Children who passed the egg challenges for confirming tolerance acquisition had significantly lower egg white-specific IgE level (P = 0.008). Similarly, those who passed milk challenges had significantly lower cow's milk-specific IgE (P = 0.002) and casein-specific IgE levels (P = 0.005). We developed a nomogram to predict the outcome of OFCs to determine the tolerance acquisition with the selected variables; lower food-specific IgE, higher total IgE, and younger age indicated a higher probability of passage. The area under the curve (95% confidence interval) was 0.623 (0.503-0.743) for egg and 0.734 (0.628-0.840) for milk.

CONCLUSIONS

Serum total IgE and food-specific IgE combined with age showed trends toward passing OFCs for confirming tolerance development. The constructed model may be used by clinicians as a practical guide for minimizing the risks of OFCs and a timely reintroduction for children with food allergies.

Feast for thought: A comprehensive review of food allergy 2021-2023

A review of the latest publications in food allergy over the past couple of years confirmed that food allergy is a major public health concern, affecting about 8% of children and 10% of adults in developed countries. The prevalence of food allergy varies around the world, with the increase being driven mainly by environmental factors, possibly together with genetic susceptibility to environmental changes. A precise diagnosis of food allergy is extremely important. Both new tests (eg, the basophil activation test) and improved optimization of information provided by existing tests (eg, the skin prick test and measurement of specific IgE level) can contribute to improving the accuracy and patients' comfort of food allergy diagnosis. Understanding the underlying immune mechanisms is fundamental to designing allergen-specific treatments that can be safe and effective in the long term. New discoveries of the immune response to food allergens, including T-cell and B-cell responses, have emerged. Novel therapeutic approaches are being trialed at various stages of development as attempts to allow for more active intervention to treat food allergy. Prevention is key to reducing the increase in prevalence. Early introduction of allergenic foods seems to be the most effective intervention, but others are being studied, and will, it is hoped, lead to modification of the epidemiologic trajectory of food allergy over time.

Red Meat Hypersensitivity and Probable Alpha-Gal Syndrome: Prevalence Among Adolescents

INTRODUCTION

It is unknown whether late adolescents represent a particular risk group for the development of red meat hypersensitivity (RMH) and alpha-gal syndrome (AGS). This age group's physiological changes and eating habits could play a determining role. This study aimed to estimate the self-reported prevalence of RMH and probable AGS among late adolescents.

METHODS

A cross-sectional study analyzed a sample of 1992 Mexican adolescents between 15 and 18 years of age. The data were obtained with a previously validated questionnaire that asked about the clinical manifestations related to red meat intake. Confidence intervals at 95% (95% CI) were estimated for proportions.

RESULTS

In total, there were 19 adolescents with RMH, a prevalence of 1.0% (95% CI: 0.6-1.5%). The main red meats related to symptoms were pork (89.5%), beef (21.1%), lamb (10.5%), and mutton (5.1%). The most frequent manifestations of RMH were gastrointestinal (73.7%), respiratory (63.2%), and cutaneous (63.2%). Once the symptoms were grouped, there were two cases of urticaria (2/19, 10.5%) and six cases with probable anaphylaxis (6/19, 31.6%). Finally, three adolescents were considered probable cases of AGS, which represents a prevalence of 0.15% (95% CI: 0.1-0.4%).

CONCLUSION

Although the prevalence of RMH in late adolescents is low, early detection is justified because approximately one-third present with severe symptoms.

Practical issues of oral immunotherapy for egg or milk allergy

Oral immunotherapy (OIT) has been recommended to reduce parental burden related to strict allergen avoidance and induce desensitization and immune tolerance for patients with long-lasting allergies to hen's eggs (HE) or cow's milk (CM). OIT should be monitored by pediatric allergists specializing in OIT and oral food challenge tests to manage allergic reactions. Although a previous history of anaphylaxis or multiple food allergies is not a contraindication to OIT, it is contraindicated if the patient has uncontrolled asthma, a malignancy, active systemic autoimmune disorders, or diseases requiring treatment with beta-blockers. A variety of OIT protocols have been de veloped to ensure better outcomes and safe up-dosing, including adjunctive therapies with biologics. This review provides insight into the practical issues of various immunotherapy options for children with HE or CM allergies.

Revisiting Fruit Allergy: Prevalence across the Globe, Diagnosis, and Current Management

Fruit allergies manifest with a diverse array of clinical presentations, ranging from localized contact allergies and oral allergy syndrome to the potential for severe systemic reactions including anaphylaxis. The scope of population-level prevalence studies remains limited, largely derived from single-center or hospital-based investigations. In this comprehensive review, we conducted a systematic literature search spanning the years 2009 to 2023, with full acknowledgment of potential analytical biases, to provide a global overview of fruit allergy prevalence. The primary mechanistic underpinning of fruit allergies stems from cross-reactivity between aeroallergens and food allergens, a consequence of structurally similar epitopes-a phenomenon recognized as pollen food allergy syndrome (PFAS). In the era of molecular allergology, numerous studies have dissected allergen components with substantial clinical relevance. Within this review, we explore important allergenic molecules found in plant-based foods, scrutinize pertinent cross-reactivity patterns, and offer insights into management recommendations. Additionally, we compare guideline recommendations to enhance clinical understanding and inform decision making.

Early Introduction of Novel and Less-Studied Food Allergens in the Plant-Based Era: Considerations for US and EU Infant Formula Regulations

Early life feeding practices may affect the long-term health of individuals, particularly in terms of the development of non-communicable diseases, such as metabolic and allergic diseases. Accumulating evidence suggests that the interplay of breastfeeding and/or formula feeding followed by the introduction of solids plays a role in the occurrence of non-communicable diseases both in the short and long term. International food allergy guidelines recommend that breastfeeding women do not need to avoid food allergens and do not recommend any infant formula for allergy prevention. Guidelines regarding solid food introduction for food allergy prevention recommend the introduction of well-cooked eggs and peanuts around 4-6 months of age, and not to delay the introduction of other food allergens. There is also an increasing trend to feed infants a plant-based or plant-forward diet and have access to infant formulas based on plant-based ingredients. The use of novel plant-based infant formulas raises a few questions reviewed in this paper: (1) Do fortified, plant-based infant formulas, compliant with US Food and Drug Administration (FDA) regulations and European Food Safety Authority (EFSA) (European) guidelines, support adequate infant growth? (2) Are plant-based infant formulas suitable for the management of cow's milk allergy? (3) Does feeding with novel, plant-based infant formulas increase the risk of food allergies to the food allergens they contain? (4) Does feeding infants plant-based food allergens in early life increase the risk of allergic and severe allergic reactions? The review of the literature indicated that (1) plant-based formulas supplemented with amino acids and micronutrients to comply with FDA regulations and EFSA guidelines, evaluated in sufficiently powered growth studies, can support adequate growth in infants; (2) currently available plant-based infant formulas are suitable for the management of CMA; (3) an early introduction and continuous intake of food allergens are more likely to prevent food allergies than to increase their risk; and (4) an early introduction of food allergens in young infants is safe.

Detection of a Thermal Stable-Soluble Protein (TSSP) as a Marker of Peanut Adulteration Using a Highly Sensitive Indirect Enzyme-Linked Immunosorbent Assay based on Monoclonal Antibodies

Food allergy represents a severe problem for many societies, including sensitive populations, academies, health authorities, and the food industry. Peanut allergy occupies a special place in the food allergy spectrum. To prevent consumption by consumers suffering from a peanut allergy, a rapid and sensitive detection method is essential to identify unintended peanut adulteration in processed foods. In this study, we produced four monoclonal antibodies (MAbs; RO 3A1-12, PB 4C12-10, PB 5F9-23, and PB 6G4-30) specific to thermo-stable and soluble proteins (TSSPs) of peanut and developed an enzyme-linked immunosorbent assay (ELISA) based on the MAbs. Among them, PB 5F9-23 MAb was firmly bound to Ara h 1, and other MAbs strongly reacted to Ara h 3 in the Western blot analysis. An antibody cocktail solution of the MAbs was used to enhance the sensitivity of an indirect ELISA, and the limit of detection of the indirect ELISA based on the antibody cocktail solution was 1 ng/ml and improved compared to the indirect ELISA based on the single MAb (11 ng/ml). The cross-reaction analysis revealed the high specificity of developed MAbs to peanut TSSPs without cross-reaction to other food allergens, including nuts. Subsequently, analyzing processed foods by indirect ELISA, all foods labeled as containing peanuts in the product description were confirmed to be positive. The results indicate that the developed antibodies exhibit high specificity and sensitivity to peanuts and can be used as bio-receptors in immunoassays or biosensors to detect intentional or unintentional adulteration of peanuts in processed foods, particularly heat-processed foods.

The alternative bile acid pathway can predict food allergy persistence in early childhood

BACKGROUND

Mechanisms underlying persistent food allergy (FA) are not well elucidated. The intestinal mucosa is the primary exposure route of food allergens. However, no study has examined intestinal metabolites associated with FA persistence. The goal of this study was to investigate intestinal metabolites and associated microbiomes in early life that aid in determining the development and persistence of FA.

METHODS

We identified metabolomic alterations in the stool of infants according to FA by mass spectrometry-based untargeted metabolome profiling. The targeted metabolomic analysis of bile acid metabolites and stool microbiome was performed. Bile acid metabolite composition in infancy was evaluated by characterizing the subjects at the age of 3 into FA remission and persistent FA.

RESULTS

In untargeted metabolomics, primary bile acid biosynthesis was significantly different between subjects with FA and healthy controls. In targeted metabolomics for bile acids, intestinal bile acid metabolites synthesized by the alternative pathway were reduced in infants with FA than those in healthy controls. Subjects with persistent FA were also distinguished from healthy controls and those with FA remission by bile acid metabolites of the alternative pathway. These metabolites were negatively correlated with specific IgE levels in egg white. The abundance of intestinal Clostridia was decreased in the FA group and was correlated with ursodeoxycholic acid.

CONCLUSION

Intestinal bile acid metabolites of the alternative pathway could be predictive biomarkers for persistent FA in early childhood. These findings require replication in future studies.

IgE-Mediated Shellfish Allergy in Children

Shellfish, including various species of mollusks (e.g., mussels, clams, and oysters) and crustaceans (e.g., shrimp, prawn, lobster, and crab), have been a keystone of healthy dietary recommendations due to their valuable protein content. In parallel with their consumption, allergic reactions related to shellfish may be increasing. Adverse reactions to shellfish are classified into different groups: (1) Immunological reactions, including IgE and non-IgE allergic reactions; (2) non-immunological reactions, including toxic reactions and food intolerance. The IgE-mediated reactions occur within about two hours after ingestion of the shellfish and range from urticaria, angioedema, nausea, and vomiting to respiratory signs and symptoms such as bronchospasm, laryngeal oedema, and anaphylaxis. The most common allergenic proteins involved in IgE-mediated allergic reactions to shellfish include tropomyosin, arginine kinase, myosin light chain, sarcoplasmic calcium-binding protein, troponin c, and triosephosphate isomerase. Over the past decades, the knowledge gained on the identification of the molecular features of different shellfish allergens improved the diagnosis and the potential design of allergen immunotherapy for shellfish allergy. Unfortunately, immunotherapeutic studies and some diagnostic tools are still restricted in a research context and need to be validated before being implemented into clinical practice. However, they seem promising for improving management strategies for shellfish allergy. In this review, epidemiology, pathogenesis, clinical features, diagnosis, and management of shellfish allergies in children are presented. The cross-reactivity among different forms of shellfish and immunotherapeutic approaches, including unmodified allergens, hypoallergens, peptide-based, and DNA-based vaccines, are also addressed.

A Meta-Analysis of the Prevalence of Wheat Allergy Worldwide

Wheat allergy is a primary disease of food allergy, and its global prevalence is unclear. This study aimed to characterize the latest worldwide prevalence of wheat allergy based on five different diagnostic methods. Study searches were conducted in Web of Science, PubMed, Ovid LWW, and Cochrane database, with a time limit of 1 January 2007 to 1 September 2022. The review and screening of the articles was undertaken by two independent reviewers. The statistical analysis was conducted by R. A total of 56 articles were finally included. The prevalence of wheat allergy was 0.63% (95% CI: 0.43-0.87%) for self-reported, 0.70% (95% CI: 0.18-1.22%) for self-reported physician-diagnosed, 0.22% (95%CI: 0.07-0.65%) for skin prick test positive, 0.97% (95% CI: 0.43-2.20%) for specific immunoglobulin E positive, and 0.04% (95% CI: 0-0.16%) for food challenge. However, food challenge can be largely subjective, and the results were only based two countries, so the prevalence of wheat allergy confirmed by food challenge may be not entirely trustworthy. In conclusion, investigating the prevalence of wheat allergy in the real world as accurately as possible will contribute to the prevention, management, and risk assessment of wheat allergy.

Allergic sensitization to foods in India and other Low-Middle-income countries

Food allergy is an important cause of morbidity, significantly affecting the quality of life of the sufferer. Most food allergy research has been undertaken in high-income countries. Here, we summarize literature regarding food allergy in India and other low-middle-income countries (LMIC). We provide summaries of self-reported adverse food reactions and food sensitization in these regions by reviewing published community-based studies of prevalence, burden, and risk factors. We identified 2 community-based studies of food allergy prevalence in Karnataka, India, which estimate that food allergy affects just 0.14% of children and 1.2% of adults. The overall prevalence of allergic sensitization to 'any' food was 26.5% in adults and 19.1% in children by serum-specific IgE; but only 4.48% in children by skin prick test. We identified a further 28 studies in other LMICs, mainly from China but also Turkey, South Africa, Ghana, Mexico, Brazil, Thailand, Philippines, and Korea. The overall prevalence of allergic sensitization to 'any' food ranged from 0.11% to 16.8% in children using serum-specific IgE and 0.14% to 9.6% in children by skin prick test. The questionnaires and skin prick testing materials used and number of allergens tested varied significantly between studies. Other than Karnataka, there is no information on prevalence of food sensitization and probable food allergy in the community in India. Similar lack of information is noted among the majority of the 136 LMICs. Where community-based studies have been undertaken, there is wide variation in the prevalence and patterns of food sensitization across different LMICs, at least partly due to variations in study methodology. International collaboration is required in order to formally assess food allergy prevalence and burden across representative samples from multiple LMICs.

[Prevalence of cow´s milk allergy and lactose intolerance among Mexican late adolescents]

OBJECTIVE

To determine the prevalence of cow´s milk allergy and lactose intolerance in a sample of late adolescents.

METHODS

Through a population-based study, data corresponding to students with aged 15 to 18 years were analyzed.

RESULTS

A total of 1992 adolescents was analized. The prevalence of cow´s milk allergy was 1.4% (95% CI: 0.2% to 0.8%) and the prevalence of lactose intolerance was 0.5% (95% CI: 0.2% to 0.8%). Adolescents with cow´s milk allergy had fewer gastrointestinal symptoms (p = 0.036), but more skin (p < 0.001) and respiratory (p = 0.028) ailments than adolescents with lactose intolerance.

CONCLUSIONS

The manifestations associated with cow's milk consumption in late adolescents seem to correspond mainly to cow´s milk allergy than to lactose intolerance.

Prevalence of Food Allergy and Common Food Allergen Among Saudi Adults in Makkah Region, Saudi Arabia

Introduction

The prevalence of food allergy (FA) in the Makkah region has received little attention, so we conducted this study to estimate the prevalence of FA in adults.

Methods

This descriptive, cross-sectional, survey-based study was conducted online among 531 participants with or without a prior diagnosis of FA. The collected data related to socio-demographics (age and gender), whether the participant had been medically diagnosed with any food allergens, and assessing the prevalence of different food allergens.

Results

Only 93 (17.5%) of the 531 people screened positive for FA; females (65.6%) predominated, with 37.6% aged 40-59. The type of food for allergy was: eggs (47%), seafood (44%), fruits (40%), nuts and legumes (37%), milk and dairy products (25%), vegetables (17%), sesame (11%), wheat (9%), soy (8%), 2% to chili peppers, and only 1% honey and chocolate.

Conclusion

Both genders were allergic to eggs, followed by seafood, fruits, nuts, and legumes, and milk and dairy products, respectively.

Development and Evaluation of a Mobile Web-based Food Allergy and Anaphylaxis Management Educational Program for Parents of School-aged Children with Food Allergy: A Randomized Controlled Trial

PURPOSE

This study aimed to develop a mobile web-based food allergy (FA) and anaphylaxis management educational program for parents of school-aged children with food allergies and evaluate its effectiveness.

METHODS

A mobile program was developed based on a web-based teaching-learning system model. Its effectiveness was subsequently evaluated using a parallel, randomized controlled pre- and post-test design. This study included 73 parents of school-aged children with food allergies. These parents were randomly assigned to either the experimental (n = 37) or control (n = 36) groups. The experimental group participated in a 2-week mobile web-based educational program that covered major topics in FA and anaphylaxis management. These topics included an understanding of food allergies and anaphylaxis, learning techniques for using an epinephrine auto-injector, and developing an emergency action plan. An educational booklet was provided to the control group. Participants completed a pre-test and two post-test questionnaires to evaluate the impact of the program. The assessment tools were the Food Allergy Knowledge Test, Food Allergy Self-Efficacy for Parents, and Food Management and Adaptation Scale. The data were analyzed using descriptive statistics, a test of homogeneity for the pre-test, an independent t-test, and repeated measures ANOVA.

RESULTS

The experimental group experienced greater improvement in the knowledge of FA (post-intervention t = 14.51, p < .001; 2 weeks post-intervention, t = 16.15, p < .001), FA self-efficacy (post-intervention t = 77.99, p < .001; 2 weeks post-intervention, t = 76.09, p < .001), and practice behavior in FA management (post-intervention t = 28.10, p < .001; 2 weeks post-intervention, t = 27.98, p < .001) after web-based FA education.

CONCLUSION

This study revealed improvements in the knowledge, self-efficacy, and practice behaviors of parents regarding FA and anaphylaxis management. Therefore, the mobile web-based educational program can contribute to the effective management of food allergies and anaphylaxis for parents of school-aged children. CRIS registration: KCT0007491.

Quality of Life in Food Allergy: Validation of the Korean Version of the Food Allergy Quality of Life Questionnaire Parent Form (K-FAQLQ-PF) and Risk Factor Analysis

PURPOSE

This study aimed to evaluate the reliability and validity of the Korean version of the Food Allergy Quality of Life Questionnaire-Parent Form (K-FAQLQ-PF) and to identify clinical characteristics related to low quality of life (QoL) in Korean children with food allergy (FA).

METHODS

Parents of 0-12-year-old patients with FA were enrolled. The English version of FAQLQ-PF was translated into Korean. Construct validation was confirmed by the Food Allergy Independent Measure-Parent Form (FAIM-PF) and the Child Health Questionnaire Parent Form 28 (CHQ-PF28). Logistic regression analyses were used to evaluate associations between potential risk factors and QoL outcomes.

RESULTS

A total of 182 patients with a median age of 5.0 years were enrolled in the study. Cronbach's α coefficient values indicating internal consistency were higher than 0.8. Intraclass correlation coefficient values for test-retest reliability were good for all age groups (r > 0.6). Total K-FAQLQ-PF scores were positively correlated with the FAIM-PF (r = 0.56, P < 0.05) and were negatively correlated with the parental impact-emotional domain in the CHQ-PF28 (r = -0.44, P < 0.05). In multivariable logistic regression analysis, low QoL was significantly associated with female sex (adjusted odds ratio [aOR], 2.07; 95% confidence interval [CI], 1.03-4.18), age ≥ 5 years (aOR, 2.84; 95% CI, 1.31-6.16), FA diagnosis before the age of 3 years (aOR, 3.96; 95% CI, 1.13-13.93), the presence of atopic dermatitis (aOR, 2.21; 95% CI, 1.07-4.57), and residence in non-metropolitan areas (aOR, 3.44; 95% CI, 1.73-6.85).

CONCLUSIONS

According to parental perceptions, the K-FAQLQ-PF is a valid and reliable tool to assess psychosocial QoL in Korean children with FAs. Age, sex, residential area, and comorbid AD can affect the QoL of pediatric patients with FA.

Prevalence, clinical presentation, and associated atopic diseases of pediatric fruit and vegetable allergy: A population-based study

BACKGROUND

In children, fruit and vegetable allergies are often overlooked compared with well-known allergies such as those to eggs, milk, and shellfish. Therefore, this study aimed to analyze fruit and vegetable allergies in children, including prevalence, types of food allergens, clinical presentation, management, and associated comorbid atopic diseases.

METHODS

In 2012, a nationwide, cross-sectional, random sampling questionnaire-based survey for common fruit and vegetable allergies was conducted in Taiwan. Information regarding these plant food allergies was collected. Physicians diagnosed food allergies according to the descriptions of convincing symptoms. Enrolled questionnaires were reviewed by expert pediatricians.

RESULTS

A total of 9,982 valid questionnaires were analyzed. The overall prevalence of fruit and vegetable allergies was 5.6% (n = 560) and 3.0% (n = 304), respectively. The most common fruit allergen was mango, followed by kiwifruit, whereas taro and bamboo shoot were the most common vegetable allergens. Meanwhile, most allergic symptoms were of the mucocutaneous tissue, followed by the upper airway and gastrointestinal tract. Most only required avoidance of allergens and not medical treatment. Children with fruit or vegetable allergies had a higher percentage of comorbid atopic dermatitis, allergic rhinitis, and asthma than those without food allergies; additionally, the proportion of comorbid atopic diseases was similar between fruit and vegetable allergies and shellfish allergy. One child developed anaphylaxis due to a corn allergy.

CONCLUSIONS

Fruits and vegetables are common food allergens in Taiwanese children who present with diverse and potentially severe symptoms. Children with plant food allergies had a percentage of comorbid atopic diseases similar to that of shellfish allergy, the most common allergen. These findings indicate the importance of considering fruit and vegetable allergies in children.

Food Allergy Prevention: Early Versus Late Introduction of Food Allergens in Children

The emergence of food allergies in children is crucial for various medical fields seeking a viable strategy for allergy prevention. The most well-recognized approach adopted by numerous health care and government institutions hinges on the delay in the introduction of food allergens, which supposedly protects infants from sensitization and decreases the possibility of allergy development. However, recent experimental findings indicate that the benefits of this approach might be overestimated, as early exposure to allergenic foods has been shown to yield more advantageous outcomes. Multiple investigations on the causes of allergic diseases report that avoiding food allergies might be related to early consumption of these allergens. Alternatively, delaying the contact with allergenic nourishments, explored in contemporary research, has been proven to result in a higher prevalence of allergies among children, originating such conditions as atopic diseases and extreme sensitization to foods. The current paper compares the two prominent strategies of allergenic food introduction, gathering the most pertinent modern evidence to distinguish whether exposure to food allergens should be delayed or advanced.

Prevalence of IgE-mediated cow milk, egg, and peanut allergy in young Singapore children

Background

The rising prevalence of food allergy reported in the United States, UK, and Australia may be attributable to the rise in peanut allergy prevalence. The food allergy prevalence in other parts of the world such as Asia is, however, less well documented.

Objective

This study aimed to evaluate the prevalence of cow’s milk, egg, and peanut allergies in a general population of Singaporean children below 30 months of age.

Methods

A total of 4,115 children from the general population who attended well-baby visits between 2011 and 2015 completed standardized questionnaires to elicit a convincing history of food allergy to estimate the population prevalence of food allergies.

Results

The prevalence of a convincing history of cow’s milk allergy was 0.51% (95% confidence interval [CI], 0.3–0.7), hen’s egg allergy 1.43% (95% CI, 1.1–1.8), and peanut allergy 0.27% (95% CI, 0.12–0.42). Of the 15 of 59 children with a convincing history of hen’s egg allergy who consented, 12 (80%) had corroborative positive skin prick tests.

Conclusion

The prevalence of food allergy, in particular peanut allergy, in children below 2 years of age is lower in this South East Asian population than reported in Western cohorts. Further research should focus on deciphering differential risk factors for food allergy across different geographical locations.

Environmental Influences and Allergic Diseases in the Asia-Pacific Region: What Will Happen in Next 30 Years?

Asia-Pacific is a populous region with remarkable variations in socioeconomic development and environmental exposure among countries. The prevalence rates of asthma and allergic rhinitis appear to have recently reached a plateau in Western countries, whereas they are still increasing in many Asian countries. Given the large population in Asia, even a slight increase in the prevalence rate will translate into an overwhelming number of patients. To reduce the magnitude of the increase in allergic diseases in next few decades in Asia, we must understand the potential factors leading to the occurrence of these disorders and the development of potential preventive strategies. The etiology of allergic disorders is likely due to complex interactions among genetic, epigenetic, and environmental factors for the manifestations of inappropriate immune responses. As urbanization and industrialization inevitably progress in Asia, there is an urgent need to curtail the upcoming waves of the allergy epidemic. Potentially modifiable risk exposure, such as air pollution, should be minimized through timely implementation of effective legislations. Meanwhile, re-introduction of protective factors that were once part of the traditional farming lifestyle might give new insight into primary prevention of allergy.

Age-related differences in characteristics of anaphylaxis in Chinese children from infancy to adolescence

Background

Little is known about anaphylaxis in Chinese children. This study aimed to determine the age-specific patterns of anaphylaxis in Chinese children.

Methods

We conducted a retrospective study of anaphylaxis cases attending an allergy department in a tertiary children's hospital.

Results

A total of 279 anaphylactic reactions in 177 patients were analyzed. Overall, 57.6% (102/177) of first anaphylaxis events occurred in infants (0-2 ys). Foods were the most common culprits (88.5%), followed by food + exercise/exercise (4.7%), and drugs (4.3%). The main food allergens were cow's milk (32.9%), egg (21.4%), and wheat (20.7%) in infants, compared with fruits/vegetables at 35.9% in preschool-age children (3-6 ys) and 31.6% in school-age children (7-12 ys). The most commonly implicated drug triggers were vaccines (n = 5, comprising DTaP n = 2, group A + C meningococcal polysaccharide vaccine n = 1, Sabin vaccine n = 1, and not specified n = 1). Among the 5 vaccine-induced anaphylaxis patients, 4 had severe cow's milk allergy. The clinical manifestations were mainly mucocutaneous (86.0%), followed by respiratory (68.8%), gastrointestinal (23.7%), neurological (10.4%), and cardiovascular (0.7%). Compared with patients of other ages, infants had higher rates of hives (0-2ys 77.4%, 3-6ys 50%,7-12ys 57.9%, 13-17ys 38.9%, p = 0.016) and vomiting (0-2ys 20.7%, 3-6ys 1.6%,7-12ys 8.8%, p < 0.001), while wheezing was more frequent in school-age children (0-2ys 21.4%, 3-6ys 25%, 7-12ys 38.6%, 13-17ys 5.6%, p = 0.017) and abdominal pain was more common in adolescents (0-2ys 2.1%,3-6ys 15.6%, 7-12ys 14.0%, 13-17ys 72.3%, p < 0.001). Regarding treatment, 9.3% of anaphylaxis events and 24.1% of life-threatening reactions were treated with epinephrine.

Conclusions

We observed age-related clinical patterns of anaphylaxis in this study, with hives and vomiting most commonly reported in infants and cardiovascular symptoms rarely reported in children. Wheat was the third most culprit food allergen after egg and milk in infancy. Education regarding more aggressive use of epinephrine in the emergency setting is clearly needed. Recognition of age-related symptoms in anaphylaxis can aid physicians in prompt diagnosis and acute management.

Global patterns in anaphylaxis due to specific foods: A systematic review

BACKGROUND

There are increasing global data relating to prevalence of food allergy and food-induced anaphylaxis; however, this is often based on surrogate measures of sensitization rather than objective symptoms at food challenge. In terms of protecting food-allergic consumers from reactions, to our knowledge, there has been no global survey assessing geographic differences in the proportion of anaphylaxis triggered by specific foods.

OBJECTIVE

We sought to identify common triggers for food-induced anaphylaxis and how these vary from country to country.

METHODS

Systematic review of relevant reports published between January 2010 and November 2020. Results were reported following PRISMA guidelines. Publications were screened and data extracted by 2 independent reviewers, and the risk of bias was assessed.

RESULTS

Sixty-five studies (encompassing 41 countries and all 6 regions as defined by the Food and Agriculture Organization of the United Nations) were included. Significant regional variations in the most common triggers of food anaphylaxis were seen; however, in general, there was good agreement between local legislative requirements for allergen disclosure and the most common allergens for each region or nation.

CONCLUSIONS

Local legislation for allergen disclosure generally reflects those allergens commonly responsible for food anaphylaxis. Cow's milk and crustaceans appear to cause a higher proportion of anaphylaxis compared to peanut in some regions.

From Allergen Molecules to Molecular Immunotherapy of Nut Allergy: A Hard Nut to Crack

Peanuts and tree nuts are two of the most common elicitors of immunoglobulin E (IgE)-mediated food allergy. Nut allergy is frequently associated with systemic reactions and can lead to potentially life-threatening respiratory and circulatory symptoms. Furthermore, nut allergy usually persists throughout life. Whether sensitized patients exhibit severe and life-threatening reactions (e.g., anaphylaxis), mild and/or local reactions (e.g., pollen-food allergy syndrome) or no relevant symptoms depends much on IgE recognition of digestion-resistant class I food allergens, IgE cross-reactivity of class II food allergens with respiratory allergens and clinically not relevant plant-derived carbohydrate epitopes, respectively. Accordingly, molecular allergy diagnosis based on the measurement of allergen-specific IgE levels to allergen molecules provides important information in addition to provocation testing in the diagnosis of food allergy. Molecular allergy diagnosis helps identifying the genuinely sensitizing nuts, it determines IgE sensitization to class I and II food allergen molecules and hence provides a basis for personalized forms of treatment such as precise prescription of diet and allergen-specific immunotherapy (AIT). Currently available forms of nut-specific AIT are based only on allergen extracts, have been mainly developed for peanut but not for other nuts and, unlike AIT for respiratory allergies which utilize often subcutaneous administration, are given preferentially by the oral route. Here we review prevalence of allergy to peanut and tree nuts in different populations of the world, summarize knowledge regarding the involved nut allergen molecules and current AIT approaches for nut allergy. We argue that nut-specific AIT may benefit from molecular subcutaneous AIT (SCIT) approaches but identify also possible hurdles for such an approach and explain why molecular SCIT may be a hard nut to crack.

Seafood Allergy in Asia: Geographical Specificity and Beyond

Asian countries have unique ways of food processing and dietary habits that may explain the observed differences in the prevalence, natural history, epidemiology and sensitization pattern of food allergic diseases when compared to western countries. Per capita consumption of seafood, including fish and shellfish, is well above the global average for many Asian countries because of their coastal geographical location and rich seafood supply. The wide availability and high abundance of seafood in Asian countries have shaped a diverse way of processing and eating this major food group. Such unique features have significant impact on the sensitization profile and allergenicity of Asians to fish and shellfish. For example, fish and shellfish are eaten raw in some countries that may promote sensitization to heat-labile allergens not otherwise seen in other regions. Fermented fish sauce is commonly used as a condiment in some countries which may promote fish sensitization. Shrimp head and shrimp roe are regarded as delicacies in some countries, but their allergen profiles are yet to be characterized. Freshwater fish and shellfish are a common food source in many Asian countries but the allergenicity of many such species remains unknown. In this review, we discuss factors that may contribute to differences in molecular profile and sensitization pattern for fish and shellfish that are observed in Asian populations and revisit the current status of seafood allergy in this part of the world. Acknowledging the similarities and differences of seafood allergy patterns between Asian and western populations can help us refine a better strategy for diagnosing and managing seafood allergy.

The global burden of illness of peanut allergy: A comprehensive literature review

Peanut allergy (PA) currently affects approximately 2% of the general population of Western nations and may be increasing in prevalence. Patients with PA and their families/caregivers bear a considerable burden of self‐management to avoid accidental peanut exposure and to administer emergency medication (adrenaline) if needed. Compared with other food allergies, PA is associated with higher rates of accidental exposure, severe reactions and potentially fatal anaphylaxis. Approximately 7%–14% of patients with PA experience accidental peanut exposure annually, and one‐third to one‐half may experience anaphylaxis, although fatalities are rare. These risks impose considerably high healthcare utilization and economic costs for patients with PA and restrictions on daily activities. Measures to accommodate patients with PA are often inadequate, with inconsistent standards for food labelling and inadequate safety policies in public establishments such as restaurants and schools. Children with PA are often bullied, resulting in sadness, humiliation and anxiety. These factors cumulatively contribute to significantly reduced health‐related quality of life for patients with PA and families/caregivers. Such factors also provide essential context for risk/benefit assessments of new PA therapies. This narrative review comprehensively assessed the various factors comprising the burden of PA.

A Review on Epidemiological and Clinical Studies on Buckwheat Allergy

BACKGROUND

Cultivated buckwheat include two species originating from China: common buckwheat (Fagopyrum esculentum) and tartary buckwheat (Fagopyrum tartaricum). Buckwheat can cause IgE-mediated allergy, including severe allergic reactions and anaphylaxis. Exposure can occure when eating buckwheat food (food allergen), when producing or handling buckwheat food (occupational exposure) or when sleeping on buckwheat husk pillows (houeshold environmental exposure).

METHODS

A search on buckwheat allergy in the medical datbase PubMed from 1970-2020.

RESULT

A number of allergenic proteins have been identified in common buckwheat (e.g., Fag e 1, Fag e 2 and Fag e 3) and in tartary buckwheat (e.g., Fag t 1, Fag t 2, Fag t 3). Clinically relevant cross-reactivity has been described between buckwheat and peanut, latex, coconut, quinoa, and poppy seed. The prevalence of buckwheat allergy in the population can be estimated as 0.1-0.4% in Japan, Korea and buckwheat consuming areas of China. Among patients in allergy clinics in different countries, 2-7% has confirmed buckwheat allergy. School studies from Japan and Korea found 4-60 cases of buckwheat-related anaphylaxis per 100,000 school children. The incidence of severe allergic reactions to buckwheat, including anaphylaxis, can be estimated as 0.1-0.01 cases per 100,000 person-years.

CONCLUSIONS

Buckwheat allergy is a neglected allegy deserving further attention but severe allergic reactions are rare.

Prevalence of Food-Hypersensitivity and Food-Dependent Anaphylaxis in Colombian Schoolchildren by Parent-Report

Background and objectives: The epidemiology of food allergy (FA) and food-dependent anaphylaxis remains unknown in Colombia. Our aim was to estimate by parent-report the prevalence of FA and food-dependent anaphylaxis in a Colombian population of schoolchildren. Materials and methods: A printed questionnaire was sent to parents of schoolchildren aged 5–12 years old from Medellín, Colombia in order to collect FA-related data. Results: Nine hundred and sixty-nine (969) parents returned the questionnaire with valid responses (response rate, 52.5%). The estimated prevalence rates (95% CI) were: adverse food reactions 12.79% (10.76–15.07), “perceived FA, ever” 10.93% (9.08–13.08), “physician-diagnosed FA, ever” 4.33% (3.14–5.81), “immediate-type FA, ever” 6.81% (5.30–8.58), “immediate-type FA, current” 3.30% (2.26–4.63), and food-dependent anaphylaxis 1.85% (1.10–2.92). The most frequently reported food allergens were milk (1.44%), fruits (0.41%), meat (0.41%), and peanut (0.3%). Sixty-one percent of “food-dependent anaphylaxis” cases sought medical attention, but only eleven percent of the cases reported the prescription of an epinephrine autoinjector. Conclusions: FA and food-dependent anaphylaxis are not uncommon among schoolchildren from Colombia. The prescription of epinephrine autoinjectors should be encouraged among health personnel for the optimal management of suspected cases of food-dependent anaphylaxis.

Allergenicity of Fermented Foods: Emphasis on Seeds Protein-Based Products

Food allergy is an IgE-mediated abnormal response to otherwise harmless food proteins, affecting between 5% and 10% of the world preschool children population and 1% to 5% adults. Several physical, chemical, and biotechnological approaches have been used to reduce the allergenicity of food allergens. Fermentation processes that contribute to technological and desirable changes in taste, flavor, digestibility, and texture of food products constitute one of these approaches. Lactic acid bacteria (LAB), used as starter cultures in dairy products, are a subject of increasing interest in fermentation of plant proteins. However, the studies designed to assess the impact of LAB on reduction of allergenicity of seed proteins are at an early stage. This review presents the current knowledge on food fermentation, with a focus on seed proteins that are increasingly used as ingredients, and its impacts on food potential allergenicity.

Factors Associated with Frequency of Peanut Consumption in Korea: A National Population-Based Study

Household peanut exposure via skin in infants with impaired skin barrier function is a risk factor for peanut allergy development. The aim of this study is to investigate the peanut consumption of Koreans using national representative data. We used data from the Korean National Health and Nutrition Examination Survey 2012-2016, consisting of data from 17,625 adults who complete the survey. Peanut intake was assessed using a 24-h recall method. Of the study population, 10,552 (59.9%), 6726 (38.2%), and 347 (1.9%) subjects were categorized into non-intake, intermittent intake, and frequent intake group, respectively. Ordered logistic regression models were used to examine the association between sociodemographic and dietary factors and the frequency of peanut intake. After adjusting for confounders, increasing age (adjusted odds ratio (aOR) 1.03; 95% confidence interval (CI) 1.03-1.04), higher education (high school graduates: aOR 1.75, 95 CI 1.39-2.19; higher than college: aOR 2.11, 95% CI 1.65-2.70), and prudent dietary scores in the second (aOR 1.71; 95% CI 1.47-1.99), third (aOR 2.53; 95% CI 2.16-2.97) and the fourth quartiles (aOR 3.72; 95%CI 3.16-4.40) were associated with a high frequency of peanut consumption. This information may be helpful not only in public health research for nutrition but also in personal management for the prevention of peanut allergy in Korea.

A 5-year retrospective review of children with peanut allergy in the largest paediatric hospital in Singapore

Background

The prevalence of peanut allergy (PA) among children has increased significantly over the past decade. Even though the prevalence of PA in Singapore is considered low, peanut is the top trigger for food-induced anaphylaxis in Singaporean children.

Objective

To describe the demographic characteristics and clinical features of children with PA.

Methods

This is a 5-year retrospective review of children diagnosed with PA based on clinical history coupled with a positive skin prick test to peanut or positive oral food challenge results.

Results

There were 269 patients (53.9% males) with a clinical diagnosis of PA. The median age at first allergic presentation for the PA group was 24 months old, with interquartile range of 13-39 months. The most common form of peanut introduced was roasted peanut. The rate of peanut anaphylaxis was 7.1%. Concomitant tree nut sensitization was found in 32.3% of this cohort, predominantly to cashew nut. Majority of them have a personal history of atopy - 75.8% with eczema, 63.6% with allergic rhinitis, and 19.7% with asthma.

Conclusion

This is the first large review of peanut-allergic children in Singapore. Prospective population-based studies are needed to establish the true prevalence and risk factors associated with the development of this potentially life-threatening condition.

Challenges of managing food allergy in the developing world

Food allergy (FA) is currently a significant health care problem in the developing world. Widely varying study populations and methodologies, the use of surrogate markers such as self report or hospitalization rates due to anaphylaxis rather than objective methods, limits robust estimation of FA prevalence in low income settings. Also, allergy is under-recognized as a clinical specialty in the developing world which compromises the chance for accurate diagnosis. In this review, most published data on food allergens from developing or low income countries are displayed. The diagnostic challenges and limitations of treatment options are discussed. It seems that FA is an under-appreciated health care issue in the developing world, and accurate determination of its burden in low-income settings represents an important unmet need. Multicenter surveillance studies, using standardized methodologies, are, therefore, needed to reveal the true extent of the problem and provide epidemiological clues for prevention. Preventive strategies should be tailored to fit local circumstances in different geographic regions. In addition, studying the gene environment interactions and impact of early life microbiota on the expression of FA in developing communities would be worthwhile. Efforts and resources should be directed toward public health education and training of health care providers dealing with food allergic patients.

The Natural Course of Immediate-Type Cow's Milk and Egg Allergies in Children

BACKGROUND

Most of children with cow's milk (CM) and hen's egg allergies are known to outgrow their diseases with time, but recent studies have demonstrated that children tend to continue to have allergic symptoms in adolescence and adulthood. The aim of this study was to investigate the natural course of CM and egg allergies in Korean children and analyze prognostic factors.

METHODS

In this retrospective study, we reviewed data of children with CM allergy and with egg allergy using medical records and parental telephone interviews. Diagnosis of CM or egg allergy was based on positive oral food challenge test or convincing history of allergic symptoms in combination with positive allergen-specific IgE. Acquisition of tolerance was defined by the absence of allergic symptoms after reintroduction of the offending foods.

RESULTS

Half of the children outgrew CM allergy at a median age of 8.7 years. CM-specific IgE level at the first reaction was a significant prognostic factor for oral tolerance in CM allergy (p < 0.05). The median age to acquire oral tolerance in 50% of patients with egg allergy was 5.6 years. Egg-specific IgE level at the first reaction and family history of allergic diseases significantly affected the prognosis in children with egg allergy (p < 0.05).

CONCLUSIONS

Half of Korean children with CM and egg allergies had symptom resolution at 8.7 and 5.6 years of age, respectively. Our results also suggest that CM- and egg-specific IgE levels at the first reaction are the most significant prognostic factors in predicting acquisition of oral tolerance.

Anaphylaxis - Lessons learnt when East meets West

The rapidly increasing prevalence of allergic disorders over the past 2 decades highlights the need to understand the epidemiology of anaphylaxis. In Europe, the United States, and Australia, the incidence of anaphylaxis is estimated to be between 60 and 950 cases per 100 000 population, with a lifetime prevalence of anaphylaxis of 0.05%-2%. The incidence appears to be increasing over time. Although the existing Asian literature is heterogeneous and limited by under-reporting, it also suggests a similar increasing trend in anaphylaxis incidence in Asia. Anaphylaxis triggers in Asia, such as the predominance of shellfish and wheat in older children and adolescents, differ from those seen in Western populations. Triggers unique to Asia such as traditional Chinese medications, galacto-oligosaccharides, and food delicacies have also been reported. Low usage of adrenaline as first-line treatment of anaphylaxis is evident across all countries and is particularly concerning. There is a need to establish prospective, standardized protocols for anaphylaxis data collection and reporting, to enhance the collective understanding of anaphylaxis and its burden, gaps in management and to identify areas for future research and intervention in each region. Understanding of the underlying reasons explaining the difference between East and West will facilitate future primary preventive strategies.

Reduction Rate of Specific IgE Level as a Predictor of Persistent Egg Allergy in Children

PURPOSE

Egg is the most common food allergen in infants. However, the natural course of egg allergy has not been fully elucidated. This study aimed to describe clinical characteristics and to identify prognostic factors associated with tolerance acquisition of immunoglobulin E (IgE)-mediated egg allergy in children.

METHODS

Children who underwent more than 1 follow-up egg white-specific immunoglobulin E (EWsIgE) test between November 2005 and November 2015 at -Severance Children's Hospital were assessed. Children were diagnosed as having IgE-mediated egg allergy based on immediate allergic reaction after egg consumption and an EWsIgE level of > 0.35 kU/L. The children were divided into "tolerant" and "persistent" groups according to tolerance acquisition defined as egg consumption without adverse allergic reactions.

RESULTS

Of 124 participants, egg allergy resolved in 101 (81.5%) children. The persistent group had more atopic dermatitis (P = 0.039), and more wheat (P = 0.009) and peanut (P = 0.012) allergies compared to the tolerant group. The EWsIgE levels at diagnosis (EWsIgE_diag) were higher in the persistent group than in the tolerant group (P = 0.001). The trend of the EWsIgE levels in the tolerant group decreased markedly over time compared to the persistent group (P < 0.001). In predicting egg allergy tolerance acquisition, the reduction rate of EWsIgE level after 12 months from diagnosis (ΔEWsIgE_12mo) tended to be more accurate than EWsIgE_diag (area under the curve: 0.835 vs. 0.731). When ΔEWsIgE_12mo was ≥ 30%, tolerance acquisition was more frequent than that of < 30% (91.9% vs. 57.9%; P < 0.001).

CONCLUSIONS

ΔEWsIgE_12mo can be used as an early independent predictor of tolerance acquisition of IgE-mediated egg allergy in children.

Allergen immunotherapy for food allergy from the Asian perspective: key challenges and opportunities

Introduction: Prevalence of food allergy is rising in different regions of the world. Asia has not been spared from this epidemic, but epidemiological data have revealed a different pattern of food allergens in this continent. Allergen-specific immunotherapy (AIT) for food allergy, which has been revolutionary as the main focus of research in recent years, needs to be adapted for the different populations in Asia. Areas covered: Recent evidence shows increasing popularity and superiority of AIT over strict food avoidance as the cornerstone of food allergy management. Asia is a distinctive continent with specific food allergy triggers, in particular, seafood, and wheat. Peanut, on the contrary, is not a common food allergen in most parts of Asia. The common Asian food allergens, as well as the rapidly developing food-specific AIT in this region will be covered in this article. Expert commentary: Evidence on oral immunotherapy for wheat allergy and preclinical data on shellfish AIT are promising. Further work should be done on resolving cross-sensitization between environmental allergens with wheat and shellfish allergens, and a modified AIT approach to enhance the safety and effectiveness of food-specific immunotherapy.

Current perspectives on tree nut allergy: a review

Tree nut (TN) allergy is common and often severe. It has become an important health concern as availability and consumption have increased. Prevalence varies by age and geographic region and appears to have increased in children. Accidental ingestion of TNs is common. Unfortunately, there is a lower likelihood of resolution of TN allergy, roughly 10%. TN-specific skin tests and serum immunoglobulin E levels can help aid in the diagnosis of TN allergy, but a careful medical history is important because a positive test in isolation is not typically diagnostic. Component-resolved diagnostic tests are being increasingly utilized and may improve accuracy. Management consists of strict avoidance of the causal nut(s) and prompt treatment of symptoms upon accidental exposure. A specific consideration with regard to the management of TN allergy is the decision to avoid all TNs or only the TNs to which a patient is clinically allergic. There are currently no data on the primary or secondary prevention of TN allergy. Treatment strategies are being evaluated.

How Different Parts of the World Provide New Insights Into Food Allergy

The prevalence and patterns of food allergy are highly variable in different parts of the world. Differences in food allergy epidemiology may be attributed to a complex interplay of genetic, epigenetic, and environmental factors, suggesting that mechanisms of food allergy may differ in various global populations. Genetic polymorphisms, migration, climate, and infant feeding practices all modulate food allergy risk, and possibly also the efficacy of interventions aimed at primary prevention of food allergy development. Approaches to diagnosis, treatment, and prevention of food allergy should thus be tailored carefully to each population's unique genetic and environmental make-up. Future research in the context of food allergy prevention should focus on elucidating factors determining differential responses between populations.

Immunoglobulin E-binding Proteins of Cooked Walnuts in Korean Children

Purpose

The immunological characteristics of young Korean children with walnut (WN) allergy and the influence of different cooking methods on WN proteins have not been evaluated to date. This study aimed to evaluate the major WN allergens identified among Korean children, together with changes in WN antigenicity caused by common cooking methods.

Methods

We enrolled children under the age of 13 years with WN serum-specific immunoglobulin (Ig) E concentrations. The protein fractions of dry-fried and boiled WN extracts were compared with those of raw WNs using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), 2-dimentional gel electrophoresis (2DE) and a proteomic analysis using electrospray ionization (liquid chromatography-mass spectrometry [LC-MS]). An immunoblotting analysis was conducted to examine IgE reactivity toward raw WNs using serum samples from 6 children with a clinical WN allergy. To determine the processed WN proteins with IgE-binding capacity, a 2D-immunoblotting analysis was performed using the pooled sera of 20 WN-sensitized children.

Results

Protein bands from raw WNs were identified at 9, 16, 28, 52, 58, and 64 kDa via SDS-PAGE. The 9- and 16-kDa protein bands were enhanced by boiling, whereas the 52- and 64-kDa bands were considerably diminished. On LC-MS analysis, of the 66 IgE-binding proteins present in raw WNs, 57 were found in dry-fried WNs, but only 4 in boiled WNs. The sera of 5 out of 6 participants reacted with the 52-kDa protein bands and those of 4 out of 6 participants reacted with the 16- and 28-kDa protein bands, respectively. Meanwhile, a 2D-immunoblotting result confirmed the presence of different binding patterns among children who consumed cooked WNs.

Conclusions

The protein profile of boiled WNs is substantially different from that of raw WNs. However, 4 proteins including prolamins remained stable after dry-frying or boiling. Further studies are needed to evaluate the clinical relevance of these findings.