IgE mediated food allergy in Korean children: focused on plant food allergy

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.

Fruit allergy and anaphylaxis in children: Culprit fruits and clinical findings

Background: Fruit allergy usually presents with mild-to-moderate symptoms but serious systemic reactions, e.g., anaphylaxis, may also occur. Objective: This study aimed to examine the clinical and laboratory characteristics of patients with fruit allergy and fruit-induced anaphylaxis. Methods: Patients diagnosed with fruit allergy at Dışkapı Hematology and Oncology Hospital and Bilkent City Hospital between January 2017 and January 2023 were included in the study. The diagnosis of anaphylaxis was made according to the European Allergy and Clinical Immunology Anaphylaxis Guideline. Results: During the study period, skin-prick tests with food allergens were performed on 9432 patients in our clinic, and fruit allergy was detected in 78 patients (0.82%). Five patients with inaccessible medical records were excluded from the study. 40 (54.8%) were boys. The median (interquartile range) age at the onset of symptoms was 72 months (12.5-144 months). Sixty-eight of the patients (93.2%) had a concomitant allergic disease, the most common of which was allergic rhinitis (n = 48 [65.8%]). The 73 patients had a history of reaction to 126 fruits. Twenty-five patients (19.8%) were allergic to multiple fruits. The most common fruit allergen was banana (22/126 [17.4%]), followed by peach (18/126 [14.2%]) and kiwi (17/126 [13.5%]). Mucocutaneous findings were observed most frequently after fruit consumption (120/126 [95.2%]). Anaphylaxis occurred in 17 patients (23.2%) with 21 fruits.The fruits most commonly associated with anaphylaxis were banana (6/21 [28.6%]) and kiwi (6/21 [28.6%]). Conclusion: Fruit allergy generally presents with mild symptoms, e.g., oral allergy syndrome, but severe systemic symptoms, e.g., anaphylaxis, can also be observed. Kiwi and banana are the fruits that most commonly cause anaphylaxis. Although more comprehensive studies are needed to comment on the development of tolerance, especially in patients with anaphylaxis, responsible fruit avoidance is still the most important strategy.

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.

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.

Location of destroyed antigenic sites of Gly m Bd 60 K after three processing technologies

Gly m Bd 60 K, which is the α subunit of β-conglycinin, is a major soybean (Glycine max) allergen. We used high hydrostatic pressure (HHP), thermal techniques, and glycation to treat β-conglycinin, which can effectively reduce the antigenicity of β-conglycinin. β-conglycinin was used to immunize New Zealand rabbits, and the antiserum had a titer > 1: 1 × 105 and an IC50 of 2.254 μg/mL. β-conglycinin was subjected to HHP, thermal techniques, and glycation and mixed with rabbit antiserum against β-conglycinin to obtain the site-specific antiserum. The overlapping gene fragments of Gly m Bd 60 K were amplified by polymerase chain reaction (PCR), then cloned into a T7 phage vector and packaged in vitro, the recombinant T7 phages were constructed. Indirect ELISA (iELISA) was used to locate the destroyed antigenic sites and, after three rounds of segment expression and identification, the C2-1 and C2-2 fragments were identified as destroyed antigenic sites of Gly m Bd 60 K. Allergenicity analysis showed that the C2-1 and C2-2 fragments reacted with allergic patients' serum, which indicated that the destroyed sites were allergic sites.

Age-Based Causes and Clinical Characteristics of Immediate-Type Food Allergy in Korean Children

PURPOSE

Age-based causes and clinical characteristics of immediate-type food allergy (FA) have not been sufficiently studied. Therefore, we investigated age-dependent clinical profiles of FA in Korean children through an extensive multicenter investigation.

METHODS

Using a case report form developed by the authors, a retrospective medical record review was performed of patients (0-18 years old) diagnosed with immediate-type FA between September 2014 and August 2015 in 14 tertiary hospitals in Korea.

RESULTS

A total of 1,353 children and adolescents, 93% younger than 7 years, were enrolled in the present study, and 1,661 cases of immediate-type FA were recorded in these patients. The 7 major causative foods were cow's milk (28.1%), hen's eggs (27.6%), wheat (7.9%), walnuts (7.3%), peanuts (5.3%), buckwheat (1.9%), and shrimps (1.9%). Categorizing the patients into 4 age groups revealed that the most common causative food was different for each age group: cow's milk (<2 years), walnuts (2-6 years), walnuts (7-12 years), and buckwheat (13-18 years). The onset time of symptoms was less than 10 minutes in 49%, between 10 and 30 minutes in 17%, and between 30 minutes and 2 hours in 34% of cases. Food-induced anaphylaxis was reported in 506 (30.5%) out of 1,661 cases, and the 7 major causes of food-induced anaphylaxis was cow's milk (27.5%), hen's eggs (21.9%), wheat (11.3%), walnuts (10.5%), peanuts (5.9%), buckwheat (4.2%), and pine nuts (3.0%). The proportion of anaphylaxis was highest in the patients allergic to buckwheat (67.7%), followed by those allergic to pine nuts (57.7%), walnuts (43.8%), wheat (43.5%), and peanuts (34.1%).

CONCLUSIONS

The 5 major causative foods of immediate-type FA in Korean children were cow's milk, hen's eggs, wheat, walnuts, and peanuts. The distribution of causative foods was considerably distinctive according to different age groups. Anaphylaxis was reported in 30.5% of immediate-type FA cases.

Update on Early Nutrition and Food Allergy in Children

With growing evidence of an increase in the prevalence, food allergy has been emerged as a new public health problem. As treatment and management of food allergy remain challenging, more attention has been paid to the importance of prevention of food allergy. Although the exact mechanism of recent epidemic is not fully understood, it is suggested that nutritional exposure in early life may play an important role in food allergy development. The underlying hypothesis is that nutritional status or food exposure in the critical period of fetal development can affect the programming of immune system and modify the risk of immunologic reactions to foods in postnatal life. We review accumulating epidemiological studies to examine an association between nutritional exposure during pregnancy or early infancy and food allergy development in children. We also discuss recent advances in the studies of the genetic and epigenetic regulation of food allergy and evaluate the role of early nutrition in food allergy development to provide a new perspective on the prevention of food allergy.

Attitudes and preferences of consumers toward food allergy labeling practices by diagnosis of food allergies

BACKGROUND/OBJECTIVES

The objective of this study was to investigate food allergens and prevalence rates of food allergies, followed by comparison of consumer attitudes and preferences regarding food allergy labeling by diagnosis of food allergies.

SUBJECTS/METHODS

A total of 543 individuals living in Seoul and Gyeonggi area participated in the survey from October 15 to 22 in 2013.

RESULTS

The results show that the prevalence of doctor-diagnosed food allergies was 17.5%, whereas 6.4% of respondents self-reported food allergies. The most common allergens of doctor-diagnosed and self-reported food allergy respondents were peaches (30.3%) and eggs (33.3%), respectively, followed by peanuts, cow's milk, and crab. Regarding consumer attitudes toward food labeling, checking food allergens as an item was only significantly different between allergic and non-allergic respondents among all five items (P < 0.001). All respondents reported that all six items (bold font, font color, box frame, warning statement, front label, and addition of potential allergens) were necessary for an improved food allergen labeling system. PLSR analysis determined that the doctor-diagnosed group and checking of food allergens were positively correlated, whereas the non-allergy group was more concerned with checking product brands.

CONCLUSIONS

An effective food labeling system is very important for health protection of allergic consumers. Additionally, government agencies must develop policies regarding prevalence of food allergies in Korea. Based on this information, the food industry and government agencies should provide clear and accurate food labeling practices for consumers.

Food allergy knowledge, perception of food allergy labeling, and level of dietary practice: A comparison between children with and without food allergy experience

BACKGROUND/OBJECTIVES

The prevalence of food allergies in Korean children aged 6 to 12 years increased from 10.9% in 1995 to 12.6% in 2012 according to nationwide population studies. Treatment for food allergies is avoidance of allergenic-related foods and epinephrine auto-injector (EPI) for accidental allergic reactions. This study compared knowledge and perception of food allergy labeling and dietary practices of students.

SUBJECTS/METHODS

The study was conducted with the fourth to sixth grade students from an elementary school in Yongin. A total of 437 response rate (95%) questionnaires were collected and statistically analyzed.

RESULTS

The prevalence of food allergy among respondents was 19.7%, and the most common food allergy-related symptoms were urticaria, followed by itching, vomiting and nausea. Food allergens, other than 12 statutory food allergens, included cheese, cucumber, kiwi, melon, clam, green tea, walnut, grape, apricot and pineapple. Children with and without food allergy experience had a similar level of knowledge on food allergies. Children with food allergy experience thought that food allergy-related labeling on school menus was not clear or informative.

CONCLUSION

To understand food allergies and prevent allergic reactions to school foodservice among children, schools must provide more concrete and customized food allergy education.

Significance of 40-, 45-, and 48-kDa Proteins in the Moderate-to-Severe Clinical Symptoms of Buckwheat Allergy

PURPOSE

This study was aimed to investigate the relationship between the allergen components and moderate-to-severe allergic reactions in patients with buckwheat allergy.

METHODS

Fifteen patients with a history of buckwheat ingestion and a buckwheat specific IgE level≥0.35 kU/L were enrolled. They were divided into 2 groups according to clinical severity scores, with 0-1 being asymptomatic-to-mild and 2-4 being moderate-to-severe symptoms. Immunoblotting was performed to investigate IgE reactivity toward buckwheat allergens and to measure intensity of each component by using a reflective densitometer.

RESULTS

The proportions of positive band to the 16 kDa (62.5% vs 0%, P=0.026) and 40-50 kDa (87.5% vs 28.6%, P=0.041) buckwheat allergens in the grade 2-4 group were higher than those in grade 0-1 group. The level of buckwheat specific IgE of grade 2-4 group was higher than that of grade 0-1 group (41.3 kU/L vs 5.5 kU/L, P=0.037). The median optical densities (ODs) of IgE antibody binding to 40-50 kDa protein were higher in the grade 2-4 group, compared with those in the grade 0-1 group (130% OD vs 60.8% OD, P=0.037).

CONCLUSIONS

The 40-50 kDa protein is implicated as an important allergen to predict moderate-to-severe clinical symptoms in Korean children with buckwheat allergy.

Immunomodulators in day to day life: a review

There are ongoing trends of immunomodulation to combat a vast range of human and animal diseases including the incurable diseases like viral diseases, cancers, autoimmune diseases and inflammatory conditions. Animate as well as non-animate factors, surrounding us are interacting with our immune system. A balanced diet should contain all essential components from energy to vitamin and trace minerals. Each of these constituent has a very special effect on the immune system starting from their development to active role in immunity therefore, the outcome of their deficiency often ends in disease. Edible items which we consume like various vegetables, spices, herbs, fruits etc., are also equally responsible in manipulation of our system either in positive or negative way. Water has biggest share in our body and acts as the main medium to support the activities of the different system of body without exception of immune system. Proper environmental temperature is essential to maintain body's functions and experiments carried out regarding the effect of temperature suggest that extremes of the temperature are often cause immunosuppression directly by acting on the cells of immunity or indirectly through inducing stress and thereby increasing production of catecholamine which are potent anti-immune molecules. Various pathogenic as well as non-pathogenic bacteria cause immune suppression and immune potentiation, respectively. Proper exercise hold a prime position in the healthy life as it supports immunity and keeps disease away. The present review deals with all these immunomodulators having both positive and negative impact on the health status of an individual.