Japanese guidelines for food allergy 2017

Skin and oral intervention for food allergy prevention based on dual allergen exposure hypothesis

Early-onset atopic dermatitis increases an individual's risk of food allergies, suggesting that transcutaneous sensitization may occur through inflamed skin. Regarding food allergy causation, the dual allergen exposure hypothesis proposes that oral allergen exposure leads to immune tolerance, whereas allergen exposure via inflamed skin causes food allergies. This hypothesis suggests that it is important to induce oral immune tolerance and prevent allergic food sensitization through the skin. This review focuses on the breakthrough evidence based on the dual allergen exposure hypothesis that involves both skin and oral interventions for food allergy prevention.

Continuous cow's milk protein ingestion during infancy may promote casein-specific IgG4 production

Background

Early supplementation and subsequent discontinuation of cow's milk formula (CMF) may increase the risk of cow's milk allergy in breast-fed infants, but little is known about the relationship between continuous CMF ingestion and cow's milk protein-specific immunoglobulin production.

Objective

This study aimed to clarify the aforesaid relationship in cow's milk-sensitized infants.

Methods

Using data from a randomized controlled trial of a Japanese birth cohort, we performed a subgroup analysis of participants who had ingested CMF in the first 3 days of life and exhibited a positive skin prick test response to cow's milk at age 6 months. We compared the differences in median titers of cow's milk-specific IgE, casein-specific IgE, and casein-specific IgG4 levels between participants who continued daily or intermittent CMF ingestion up to age 6 months (the "continuous group") and participants who discontinued CMF ingestion before age 6 months (the "discontinued group").

Results

From among 462 trial participants, 49 (10.6%) were included in this study (21 in the continuous group and 29 in the discontinued group). The median titer of cow's milk-specific IgE was 0.17 kUA/L (interquartile range [IQR] = <0.10 to 0.57) in the continuous group and 0.66 kUA/L (IQR = 0.49-1.18) in the discontinued group (P = .0008). The median titer of casein-specific IgE was <0.10 kUA/L (IQR = <0.10 to 0.15) in the continuous group and <0.10 kUA/L (IQR = <0.10 to 0.37) in the discontinued group (P = .51). The median titer of casein-specific IgG4 was 2.58 mgA/L (IQR = 0.77-6.73) in the continuous group and 0.09 mgA/L (IQR = 0.07-0.13) in the discontinued group (P < .0001).

Conclusion

Continuous CMF ingestion may promote casein-specific IgG4 production in cow's milk-sensitized infants.

Prevalence of food allergy increased 1.7 times in the past 10 years among Japanese patients below 6 years of age

BACKGROUND

While food allergy (FA) has been increasingly recognized as a growing public health burden worldwide, epidemiological studies on FA in Japan are limited.

METHODS

This was a noninterventional, observational study using the administrative claims data from 2010 to 2019 (10 years). Patients with physician-diagnosed FA in Japan (prevalent cohort) were divided into high-risk or low-risk cohorts using adrenaline prescription. The high-risk cohort was further divided into anaphylaxis or nonanaphylaxis cohort based on the occurrence of anaphylaxis or a serious allergic reaction (SAR) during 1 year after adrenaline prescription. The primary objective was to examine yearly prevalence of FA. The secondary objectives were to describe demographics/clinical characteristics and healthcare resource utilization (HCRU), to evaluate the number of occurrences of anaphylaxis/SAR in the high-risk cohort, and the impact of anaphylaxis/SAR on HCRU.

RESULTS

The overall standardized prevalence rate was 0.325% (95% confidence interval [CI], 0.311-0.339) in 2010 and 0.797% (95% CI, 0.790-0.804) in 2019 and predominant in patients age <6 years (preschool; 3.377% [95% CI, 3.229-3.525] in 2010 and 5.726% [95% CI, 5.663-5.789] in 2019). Majority of FA patients (>80%) were children/adolescent throughout the 10 years. While high-risk cohort was a relatively minor population (8.5% in the prevalent cohort in 2019), the occurrence of anaphylaxis/SAR in the high-risk cohort was 227,690/100,000 patient-years. Multivariate analysis showed a significant increase in HCRU variables in the anaphylaxis versus nonanaphylaxis cohort (e.g., 2.08 [95% CI, 2.05-2.11] times more FA-related outpatient visits).

CONCLUSIONS

Prevalence of FA increased in a statistically significant way from 2010 to 2019; 1.7-fold increase was observed in patients <6 years old. Patients in the high-risk cohort appear to have suffered from frequent anaphylaxis/SAR, highlighting an unmet medical need for FA patients at "high-risk," considering the unavailability of approved medications to prevent anaphylaxis/SAR.

Diagnosis and management of food allergy-induced constipation in young children-An EAACI position paper

The recognition of constipation as a possible non-Immunoglobulin E (IgE)-mediated allergic condition is challenging because functional constipation (unrelated to food allergies) is a common health problem with a reported worldwide prevalence rate of up to 32.2% in children. However, many studies in children report challenge proven cow's milk allergy and constipation as a primary symptom and have found that between 28% and 78% of children improve on a cow's milk elimination diet. Due to the paucity of data and a focus on IgE-mediated allergy, not all food allergy guidelines list constipation as a symptom of food allergy. Yet, it is included in all cow's milk allergy guidelines available in English language. The Exploring Non-IgE-Mediated Allergy (ENIGMA) Task Force (TF) of the European Academy for Allergy and Clinical Immunology (EAACI) considers in this paper constipation in the context of failure of standard treatment and discuss the role of food allergens as culprit in constipation in children. This position paper used the Delphi approach in reaching consensus on both diagnosis and management, as currently published data are insufficient to support a systematic review.

Ultra-processed food intake and food allergy in children and adolescents

This study aimed to describe the dietary intake of ultra-processed foods (UPF) by children and adolescents with food allergy (FA) and to verify a possible association between the UPF intake with clinical characteristics and nutritional status in this group. This cross-sectional study included 110 children and adolescents with single or multiple FA IgE and non-IgE mediated. We evaluated food intake using the NOVA classification through the three 24-h recalls. The average contribution of UPF to total energy intake (calories) ranges from 21% in the first quartile to 43% in the last quartile (mean UPF intake 33.9 ± 14.9%). After binary logistic regression, an association was verified between dietary intake of UPF (>4th quartile) as a percentage of total energy intake and having multiple food allergies (OR 4.102; 95% CI - 1.331 to 12.643; p = .014). We concluded that children and adolescents with FA consumed a higher amount of UPF.

Effect of Addition of Tannin Extract from Underutilized Resources on Allergenic Proteins, Color and Textural Properties of Egg White Gels

Tannins, present in numerous plants, exhibit a binding affinity for proteins. In this study, we aimed to exploit this property to reduce the concentration of allergenic egg white proteins. Tannins were extracted, using hot water, from the lyophilized powder of underutilized resources, such as chestnut inner skin (CIS), young persimmon fruit (YPF), and bayberry leaves (BBLs). These extracts were then incorporated into an egg white solution (EWS) to generate an egg white gel (EWG). Allergen reduction efficacy was assessed using electrophoresis and ELISA. Our findings revealed a substantial reduction in allergenic proteins across all EWGs containing a 50% tannin extract. Notably, CIS and BBL exhibited exceptional efficacy in reducing low allergen levels. The addition of tannin extract resulted in an increase in the total polyphenol content of the EWG, with the order of effectiveness being CIS > YPF > BBL. Minimal color alteration was observed in the BBL-infused EWG compared to the other sources. Additionally, the introduction of tannin extract heightened the hardness stress, with BBL demonstrating the most significant effect, followed by CIS and YPF. In conclusion, incorporating tannin extract during EWG preparation was found to decrease the concentration of allergenic proteins while enhancing antioxidant properties and hardness stress, with BBL being particularly effective in preventing color changes in EWG.

Risk subgroups and intervention effects among infants at high risk for peanut allergy: A model for clinical decision making

BACKGROUND

The Learning Early About Peanut Allergy (LEAP) trial showed that early dietary introduction of peanut reduced the risk of developing peanut allergy by age 60 months in infants at high risk for peanut allergy. In this secondary analysis of LEAP data, we aimed to determine risk subgroups within these infants and estimate their respective intervention effects of early peanut introduction.

METHODS

LEAP raw data were retrieved from ITNTrialShare.org. Conditional random forest was applied to participants in the peanut avoidance arm to select statistically important features for the classification and regression tree (CART) analysis to group infants based on their risk of peanut allergy at 60 months of age. Intervention effects were estimated for each derived risk subgroup using data from both arms. Our main model was generated based on baseline data when the participants were 4-11 months old. Specific IgE measurements were truncated to account for the limit of detection commonly used by laboratories in clinical practice.

RESULTS

The model found infants with higher predicted probability of peanut allergy at 60 months of age had a similar relative risk reduction, but a greater absolute risk reduction in peanut allergy with early introduction of peanut, than those with lower probability. The intervention effects were significant across all risk subgroups. Participants with baseline peanut sIgE ≥0.22 kU/L (n = 78) had an absolute risk reduction of 40.4% (95% CI 27.3, 51.9) whereas participants with baseline peanut sIgE<0.22 kU/L and baseline Ara h 2 sIgE <0.10 kU/L (n = 226) had an absolute risk reduction of 6.5% (95% CI 2.6, 11.0). These findings were consistent in sensitivity analyses using alternative models.

CONCLUSION

In this study, risk subgroups were determined among infants from the LEAP trial based on the probability of developing peanut allergy and the intervention effects of early peanut introduction were estimated. This may be relevant for further risk assessment and personalized clinical decision-making.

Experiences and perceptions of people with celiac disease, food allergies and food intolerance when dining out

Introduction

Eating out is a common practice in modern society. Celiac disease (CeD) and food allergy (FA) are among the most common conditions responsible for adverse reactions to food. Despite their different origins, both require treatment with restrictive diets (avoidance of gluten and/or specific allergens) and this results posing similar challenges when eating out. Our objective was to learn about the experiences/perceptions of consumers with CeD and FA when dining out, as well as the challenges they face in food service environments.

Methods

An ad hoc questionnaire was used to record consumer perceptions, food service characteristics and resulting adverse reactions.

Results

377 individuals living in Santiago, Chile, provided complete information and were analyzed (160 CeD, 105 FA). 301 participants (79.8%) declared eating out, 33.6% reported experiencing an adverse reaction at least once while eating out. 94.4% of the 377 participants believed that the serving staff had little or no knowledge about his/her condition. Consumers reporting symptoms as severe adverse reactions were more common among celiac than allergic patients (p < 0.001).

Discussion

The study showed no significant differences based on consumer-related characteristics (p:NS). The consequences of eating out did not vary based on individual's data, including diagnosis, age, frequency of eating out, adverse reactions experienced, or intensity. These findings suggest that the most important determinants of risk associated with eating out are characteristics of the food service, like availability of information, staff training, and establishment's facilities like equipment available, exclusive utensils for customers with special dietary needs and kitchen and bathrooms organization.

Disaster Preparedness for Children With Food Allergies During the 2016 Kumamoto Earthquake-Observational Study

A series of 3 direct-type earthquakes with magnitude ≥6 occurred in the Kumamoto Prefecture, located in the western area of Japan, between April 14 and 16, 2016. Children with food allergies (FA) had difficulty procuring allergen-free meals during this period due to the infrastructure shutdown. We investigated the status of children with FA during the 2016 Kumamoto Earthquake and their behavioral changes after the disaster. We conducted a survey of the parents of 59 children with FA (median: 4 years and 1 month old) who were clinically followed up at our institution. They were questioned about their behavior change to allergen removal and using allergen-free foods during the disaster. Forty-seven (79.7%) children with FA were evacuated immediately after the earthquake and returned to their homes after the restoration of lifelines. Most stayed in their cars, while a few took shelter at public evacuation sites. Thirty-eight children (64.4%) had difficulty obtaining allergen-free food, and 29 children with FA (49.2%) did not have a stockpile at home. Thirty-three children with FA (55.9%) consumed allergen-free foods acquired primarily through relief supplies. Forty-seven guardians (79.7%) insisted that stockpiling allergy-friendly foods at home should be a part of future disaster planning. Stockpiles of allergen-free food were not sufficient in most households. Awareness of self-stockpiling allergen-free foods, reassessing public stockpiling, and establishing a system to provide information regarding relief supplies to evacuees outside evacuation centers are important for disaster planning in children with FA.

Safety of Oral Food Challenge for Individuals with Low Egg White and Ovomucoid-Specific IgE Antibodies

INTRODUCTION

During an oral food challenge (OFC), there is a risk of adverse reactions, including anaphylaxis. Therefore, the physician should carefully conduct the OFC. This study aimed to evaluate the OFC results in individuals with low levels of egg white (EW)- and ovomucoid (OVM)-specific immunoglobulin E (sIgE) and the safety of a hen's egg (HE) OFC in these individuals.

METHODS

A total of 2,058 individuals with low EW- or OVM-sIgE underwent HE-OFC at two institutions in Kumamoto prefecture, located in the western area of Japan, between January 1, 2017, and December 31, 2021, within 1 year of recorded sIgE measurements. The ImmunoCAP systems were used to measure sIgEs. The HE-OFC test was performed according to the 2017 Food Allergy Guidelines in an open and unblinded method.

RESULTS

Five hundred and one individuals (24.3%) had low EW-sIgE levels (class 2 or lower), and 926 (45.0%) had low OVM-sIgE levels (class 2 or lower). Individuals with low EW-sIgE had lower total IgE and OVM-sIgE than did those with high EW-sIgE (greater than class 2). Those with low OVM-sIgE had lower total IgE and EW-sIgE than did those with high OVM-sIgE (greater than class 2). Among the individuals with low EW-sIgE, 86.4% (433/501 cases) passed the OFC without symptoms. Among the individuals with low OVF-sIgE, 82.6% (765/926 cases) passed the OFC without symptoms.

CONCLUSION

More than 80% of individuals with suspected IgE-dependent HE allergy and low levels of EW- or OVM-specific IgE were able to consume at least a small amount of HE. As the OFC results are independent of the loading dose in cases with low EW- or OVM-sIgE, a medium-dose HE-OFC may be performed safely in individuals with no history of anaphylaxis.

Low Allergenicity in Processed Wheat Flour Products Using Tannins from Agri-Food Wastes

The present study aimed to investigate the effect of the addition of tannins from unutilized resources on wheat allergen reduction, antioxidant properties, and quality by substituting 3%, 5%, and 10% of the flour with chestnut inner skin (CIS) and young persimmon fruit (YPF) powders to produce cookies. The enzyme-linked immunosorbent assay and Western blotting showed significantly lower wheat allergen content in CIS- or YPF-substituted cookies than in control cookies, and this effect was pronounced for CIS-substituted cookies. In addition, the tannin content and antioxidant properties of the CIS- or YPF-substituted cookies were markedly higher than those of the control cookies. Quality analysis of the CIS- and YPF-substituted cookies showed that the specific volume and spread factor, which are quality indicators for cookies, were slightly lower in the CIS- and YPF-substituted cookies than in the control cookies. Compared to the control, CIS substitution did not affect the breaking stress and total energy values of the cookies; however, YPF substitution at 10% increased these values. Color was also affected by the addition of CIS and YPF. The results suggest that the addition of CIS and YPF can reduce wheat allergens in cookies and improve tannin content and antioxidant properties.

Enhanced early skin treatment for atopic dermatitis in infants reduces food allergy

BACKGROUND

Early-onset atopic dermatitis is a strong risk factor for food allergy, suggesting that early effective treatment may prevent transcutaneous sensitization.

OBJECTIVES

This study tested whether enhanced treatment of atopic dermatitis to clinically affected and unaffected skin is more effective in preventing hen's egg allergy than reactive treatment to clinically affected skin only.

METHODS

This was a multicenter, parallel-group, open-label, assessor-blind, randomized controlled trial (PACI [Prevention of Allergy via Cutaneous Intervention] study). This study enrolled infants 7-13 weeks old with atopic dermatitis and randomly assigned infants in a 1:1 ratio to enhanced early skin treatment or conventional reactive treatment using topical corticosteroids (TCSs). The primary outcome was the proportion of immediate hen's egg allergy confirmed by oral food challenge at 28 weeks of age.

RESULTS

This study enrolled 650 infants and analyzed 640 infants (enhanced [n = 318] or conventional [n = 322] treatment). Enhanced treatment significantly reduced hen's egg allergy compared with the conventional treatment (31.4% vs 41.9%, P = .0028; risk difference: -10.5%, upper bound of a 1-sided CI: -3.0%), while it lowered body weight (mean difference: -422 g, 95% CI: -553 to -292 g) and height (mean difference: -0.8 cm, 95% CI: -1.22 to -0.33 cm) at 28 weeks of age.

CONCLUSIONS

This study highlighted the potential of well-controlled atopic dermatitis management as a component of a hen's egg allergy prevention strategy. The enhanced treatment protocol of this trial should be modified before it can be considered as an approach to prevent hen's egg allergy in daily practice to avoid the adverse effects of TCSs. After remission induction by TCSs, maintenance therapy with lower potency TCSs or other topical therapies might be considered as alternative proactive treatments to overcome the safety concerns of TCSs.

Pearls and Pitfalls of Weaning an Infant with Severe Atopic Dermatitis and Sensitization/Allergy to Food

Atopic dermatitis (AD) is a common chronic inflammatory skin disorder in childhood. Skin barrier impairment exposes infants to food allergens, potentially causing sensitization followed by IgE-mediated food allergy. We describe the case of an infant with severe AD in whom several sensitizations to foods are detected, with consequently difficult weaning, and a history of anaphylaxis to cashew nut. Foods for which skin tests were negative were introduced into the infant's diet. Then, when AD control was managed, oral food challenges (OFCs) for foods to which the patient was sensitized, with the exception of cashew nut, were performed. The simultaneous presence of sensitization toward multiple foods made it difficult to introduce them using classic OFC. Therefore, it was decided to perform the low-dose, gradual controlled OFC. This led to an introduction of sensitized foods into the infant's diet, with the exception of cashew nut, avoiding allergic reactions. Absolute recommendations on how, when, and where to perform OFCs with allergenic food to which the child with AD is sensitized are lacking so far. In our opinion, OFCs and the subsequent ntroduction of allergenic foods should be individualized, evaluating some factors such as their social and nutritional importance, the patient's age and clinical phenotype (including the history of anaphylaxis), and the sensitization profile. There is agreement on the fact that the dietary approach in children with moderate-severe AD should no longer include a strict elimination diet. We believe that an early, gradual controlled introduction of all allergenics to identify the amount of food tolerated in the absence of reactions, even if low dose, may improve patients' and families' quality of life. However, even if discussing a vast relevant literature, the limitation of our work is that we describe the management of a single patient. Extensive and high-quality research is needed in this field to improve the available evidence in the area.

Relationship between eliciting doses and the severity of allergic reactions to food

PURPOSE OF REVIEW

Food allergies with low thresholds are associated with frequent accidental allergic reactions. Severe reactions attributable to accidental ingestion often result in a poor quality of life. Nevertheless, no evidence of a relationship between a low threshold dose and the severity of symptoms exists. Therefore, we evaluated recent data regarding the threshold of food allergies based on the oral food challenge (OFC). We also proposed a stepwise OFC method to identify threshold and consumable doses.

RECENT FINDINGS

A higher specific IgE level and a history of food-induced anaphylaxis were related to low threshold doses and severe reactions during the OFC. In addition, a low threshold dose was not directly correlated with severe reactions. Performing a stepwise OFC may help safely clarify consumable doses and prevent the complete avoidance of allergy-causing foods.

SUMMARY

Severe food allergies with high specific IgE levels are associated with lower thresholds and more severe reactions. However, the threshold is not directly related to the severity of food-induced allergic symptoms. Identifying a well tolerated consumable dose using a stepwise OFC may help manage food allergies.

Food Allergens and Essential Oils in Moisturizers Marketed for Children in Japan

Introduction Personal skincare leave-on products increase the risk of food allergies. Parents must be imparted with an elevated degree of cognizance regarding the allergenic nature of pediatric skincare products. Material and methods We aimed to examine the data inferred from the promotional material on labeling these products about their proclivity to elicit skin sensitization. This study investigated the relationship between food allergens and essential oil ingredients and highlighted marketing terms, product prices, and ratings of moisturizers for children that are sold on Amazon, Japan. We searched and recorded the product labels and website marketing terms, price (per gram or milliliter), the number of reviews, and allergens and investigated the relationship between the percentage of food allergens in those products and marketing terms, price, and the number of Amazon reviews. Results Among the 164 pediatric skincare products we included, 144 (87.8%) that were manufactured in Japan were the most common; 7 (4.3%), 15 (9.1%), 23 (14.0%), 24 (14.6%), and 54 (32.9%) contained the eight regulated food allergens, grain, nut, fruit, and essential oils, respectively. Marketing terms emphasizing "natural/organic" were more likely to contain grain allergens and essential oils and were more expensive with and without "organic" labeling, respectively, whereas those labeled with marketing terms emphasizing "hypoallergenic" were less likely to contain fruit allergens or essential oils. Products with fewer Amazon reviews were more likely to use the marketing term "natural/organic" and had a higher grain allergen content. Conclusion In Japan, 4.3% of children's skincare products sold on Amazon contain eight food allergens that should obligatorily be labeled when included in food products. In addition, more than 10% of these children's skin care products contain ingredients derived from nuts, while more than 30% contain fruit extracts or essential oils.

The protective effect of butylated hydroxytoluene and 3-hydroxytyrosol on food allergy in mice

OBJECTIVE

To test the effect of two dietary antioxidants: butylated hydroxytoluene (BHT) and 3-hydroxytyrosol (3-HT) in experimental food allergy.

METHODS

BALB/c mice maintained on control diet or diet with BHT or 3-HT were sensitized with ovalbumin (OVA) or saline through transdermal exposure. Plasma OVA-specific IgE (OVA-IgE) and IgG1 (OVA-IgG1) antibody levels were determined using ELISA. Sensitized mice were challenged by oral gavage with OVA. Rectal temperature (RT) was measured before and after challenge. Mast cell degranulation was quantified by measuring the plasma levels of mouse mucosal mast cell protease-1 (mMCP-1). Flow cytometry was carried out to evaluate the percentage Th2 cells from the spleen.

RESULTS

Mice on either a 3-HT or BHT diet showed a significantly decreased IgE response to OVA sensitization and less severe anaphylaxis, as evidenced by a diminished drop in body temperature, attenuated clinical signs, a more rapid recovery and decreased mast cell degranulation (as determined by lower plasma mMCP-1 levels).

CONCLUSION

The present study indicates two dietary antioxidants: BHT and 3-HT may be protective against experimental food allergy. These results suggest 3-HT and BHT could potentially be useful for prevention of food allergy.

Pollen Food Allergy Syndrome in Japanese Children and Adolescents: Risk Factors and Pollen Sensitisation

Pollen food allergy syndrome (PFAS) is caused by cross-reactivity with pollen; however, not all-pollen-sensitised individuals develop PFAS, and studies on the characteristics of PFAS development are limited in Japan. We investigated the prevalence and risk factors for the development of PFAS in Japanese children and adolescents sensitised to pollen and their association with pollen-specific IgE levels. The characteristics of PFAS were investigated in patients with allergies aged 3-18 years who visited Dokkyo Medical University Hospital between January 2016 and December 2019. Specific IgE levels for alder, Japanese cedar, ragweed, and orchard grass were measured in patients sensitised to any of the pollens. Patients were categorised into preschool (G1), elementary school (G2), and middle-high school (G3) groups. Overall, 600 patients were enrolled. The prevalence of PFAS was 8.5% in G1, 20% in G2, and 36.3% in G3. Multivariate logistic regression analysis demonstrated strong associations between the risk of developing PFAS and older age (odds ratio (OR), 1.12; 95% confidence interval (CI), 1.06-1.19; P < 0.001), seasonal allergy rhinitis (OR, 6.93; 95% CI, 1.59-30.34; P = 0.010), and alder sensitisation (OR, 6.20; 95% CI, 2.66-14.49; P < 0.001). Spearman's correlation revealed statistically significant positive correlation between each pollen-specific IgE level; high pollen-specific IgE levels were also a risk factor. The OR for being sensitised to all four species was 36.83 (95% CI, 8.93-151.83, P < 0.001) when compared with Japanese cedar alone. Alder was most relevant, with an alder-specific IgE level cutoff value of 2.54 UA/mL. The sensitivity was 78.9%, and the specificity was 70.9%. In conclusion, preschool children develop PFAS with alder sensitisation, and higher pollen-specific IgE levels and increased number of pollen sensitisations are risk factors for developing PFAS.

Omalizumab is effective for a patient with pollen-food allergy syndrome who experienced intractable lip edema

Pollen-food allergy syndrome (PFAS) is an immunoglobulin E (IgE)-mediated allergic reaction caused when patients with pollen allergy ingest food having cross-reactivity with pollen. To date, no effective treatment method for this has been established. Here we report the case of a patient with PFAS who experienced lip edema, causing difficulties in treatment. This report describes the case of a 12-year-old boy with perennial allergic rhinitis since the age of 8 years. After ingesting fresh fruits and raw vegetables at the age of 11 years, he started to experience lip edema repeatedly. Thus, the patient was referred to our department. Based on the results of serum antigen-specific IgE, prick-to-prick, and allergen component tests, he was diagnosed with PFAS. He has been instructed to avoid causative food. Furthermore, the treatment using an antihistamine and antileukotriene receptor antagonist was initiated for pollen allergy. Sublingual immunotherapy (SLIT) for Japanese cedar pollen was initiated because the patient experienced severe nasal allergy symptoms during the dispersal season of this pollen. These treatments alleviated the nasal symptoms; however, the lip edema persisted. Omalizumab administration improved the lip edema. The combination of SLIT and omalizumab may be an effective treatment option for patients with PFAS.

Nutritional Management of Children with Food Allergies

Purpose of the Review

The purpose of the review is to review the evidence for the nutritional management of paediatric food allergy and provide a practical approach for healthcare professionals working in this area.

Recent Findings

Dietary elimination remains the mainstay for management of food allergies in children. However, the elimination of food allergens increases the risk for growth faltering, micronutrient deficiencies and feeding difficulties. Breastmilk remains the ideal source of nutrition for infants, but when not available, the vast majority will tolerate an extensively hydrolysed formula, and rice hydrolysate has also been suggested as a suitable alternative. Only in severe cases, including anaphylaxis, eosinophilic oesophagitis and growth faltering, is an amino acid formula indicated. The early introduction of peanut and egg and avoiding the delay in the introduction of other allergens, when not already allergic, has been highlighted by recent studies.

Summary

Whilst the elimination of allergens increases the risk of developing poor growth, micronutrient deficiencies and feeding difficulties, optimal, early dietary input, including advice on active introduction of allergens and alternative feeds, ideally from a registered dietitian/nutritionist, may be prevent and improve outcomes.

Effects of regular soy formula intake between 1 and 2 months of age on food sensitization in infancy

BACKGROUND

The effects of regular soy formula (SF) intake on the development of food sensitization in infancy remain unclear. This study aimed to assess the effects of regular SF intake between 1 and 2 months of age on food sensitization development by 6 months of age.

METHODS

Using data from a randomized controlled trial of a birth cohort from four Japanese hospitals that assessed cow's milk allergy development, we performed a retrospective cohort study of 235 infants who avoided cow's milk formula and supplemented breastfeeding with SF as required between 1 and 2 months of age. Regular SF intake was defined as SF consumption of ≥14 days per month and ≥1350 ml per month. Food sensitization was defined as positive skin prick test reactions to hen's egg, cow's milk, wheat, and/or soy. Using multivariable logistic regression models that adjusted for parental, perinatal, and environmental factors, we calculated the adjusted odds ratios of regular SF intake for food, hen's egg, and cow's milk sensitization by 6 months of age.

RESULTS

From the 235 participants, 114 (48.5%) had regular SF intake. The adjusted odds ratios of regular SF intake for food, hen's egg, and cow's milk sensitization were 0.32 (95% confidence interval: 0.16-0.62, p = .0007), 0.42 (0.20-0.88, p = .02), and 0.33 (0.14-0.81, p = .02), respectively.

CONCLUSION

Regular SF intake between 1 and 2 months of age in infants avoiding cow's milk formula was significantly associated with a reduced risk of food sensitization in infancy.

Comparison of Acute Phase Thymus and Activation-Regulated Chemokine (TARC) Levels in Food Protein-Induced Enterocolitis Syndrome and IgE-Dependent Food Allergy

Introduction: Patients with food protein-induced enterocolitis syndrome (FPIES) have elevated thymus and activation-regulated chemokine (TARC) levels in the acute phase. However, to the best of our knowledge, no study has evaluated TARC levels in the acute phase of immunoglobulin E-dependent food allergy (IgE-FA). If TARC elevation is a specific response to FPIES among FAs, TARC measurement may help distinguish between FPIES and IgE-FA. Thus, we investigated acute phase TARC levels in patients with FPIES and IgE-FA. Methods: Thirty-one episodes in 16 patients with FPIES and 20 episodes (13 were anaphylaxis) in 20 patients with IgE-FA were included. Patients with eczema were excluded. Serum TARC levels within 6 h of allergic reaction onset and age-adjusted TARC ratios (TARC levels divided by age-specific normal TARC values) were compared between the groups. Results: The median age was 1.1 and 3.6 years in the FPIES and IgE-FA groups, respectively (P < 0.001). The median (range) serum TARC (pg/mL) levels were significantly higher in the FPIES group than in the IgE-FA group [1,283 (410-3,821) versus 377 (109-1,539); P < 0.001]. The median (range) age-adjusted TARC ratios were also significantly higher in the FPIES group [2.56 (0.57-7.86) versus 1.08 (0.15-2.17); P < 0.001]. The area under the curve (AUC) for TARC to distinguish FPIES from IgE-FA was 0.926, and the AUC for the age-adjusted TARC ratio was 0.850. The odds ratio for FPIES diagnosis per 1,000 pg/mL increase in TARC was 31.6 (P = 0.002), and the odds ratio adjusted by age was 17.1 (P = 0.016). Conclusion: Acute phase TARC levels were higher in patients with FPIES than in patients with IgE-FA. The increase in acute phase TARC levels was considered to be a specific response to FPIES among FAs. Measurement of TARC levels in the acute phase may help differentiate FPIES from IgE-FA.

Allergy from perspective of environmental pollution effects: from an aspect of atopic dermatitis, immune system, and atmospheric hazards-a narrative review of current evidences

Environmental pollution has become more diversified in recent years as technologies for urbanization is increasingly more advanced. Several environmental factors such as air and water pollutants have been linked to allergic symptoms. For instance, because of industrialization for city development in many countries, polluted soil or tiny particles in the air could result in an even more hazardous environment for people to reside. Aside from the aspects of environmental issues, other newly emerging factors such as the electromagnetic field (EMF) also require further investigation. Here, in this narrative review, we focused on allergens from atmospheric and water pollution, hygiene improvement, changes in food trend, and residential environmental pollution. Current evidences regarding the association between various pollutants and the potential clinical diseases could be induced. For people with high skin exposure to air pollutants such as PM 2.5, PM 10, or sulfur dioxide, potential onset of dermatological allergic events should be alerted. The mechanisms involved in allergic diseases are being discussed and summarized. Interactions between immunological mechanisms and clinical implications could potentially provide clearer view to the association between allergic status and pollutants. Moreover, understanding the mechanistic role of allergens can raise awareness to global environment and public health.

Long-term outcomes of oral immunotherapy for anaphylactic egg allergy in children

Background

Studies of long-term oral immunotherapy (OIT) in children with anaphylactic egg allergy are limited.

Objective

Our aim was to investigate the long-term outcomes of OIT for anaphylactic egg allergy.

Methods

The participants included children (aged ≥ 5 years) with a history of anaphylaxis in response to eggs and objective reactions to oral food challenge (OFC) with 250 mg of egg protein. In the OIT group, the home starting dose of egg protein set during 5 days of hospitalization was ingested once daily and gradually increased to 1000 mg. Over the next year, participants temporarily discontinued OIT for 2 weeks and underwent OFC with 3100 mg of egg protein annually until they passed. The historical control group comprised patients who did not receive OIT and repeated OFCs annually.

Results

In the OIT group (n = 20), the baseline median egg white- and ovomucoid-specific IgE levels were 45.5 and 38.5 kUA/L, respectively. The rate of passing OFC with 3100 mg of egg protein gradually increased in the OIT group, with rates of 20% at 1 year, 35% at 2 years, and 55% at 3 years, which were significantly higher than the rates in the historical control group at 3 years (5% [P < .001]). In the OIT group, 5 anaphylaxis events (0.04%) occurred at home, and 1 participant required intramuscular adrenaline. Furthermore, egg white- and ovomucoid-specific IgE levels decreased significantly after 3 years in both groups, whereas in the OIT group, these specific IgG and IgG4 levels increased significantly after a year.

Conclusion

Long-term OIT accelerated immunologic changes and enabled ingestion of 3100 mg of egg protein in half of the participants with anaphylactic egg allergy.

Development of mouse model for oral allergy syndrome to identify IgE cross-reactive pollen and food allergens: ragweed pollen cross-reacts with fennel and black pepper

Oral allergy syndrome (OAS) is an IgE-mediated immediate food allergy that is localized to the oral mucosa. Pollen food allergy syndrome (PFAS), a pollinosis-associated OAS, is caused by cross-reactivity between food and pollen allergens. However, we need to more precisely understand the underlying pathogenesis of OAS/PFAS. In the present study, we developed a method to comprehensively identify cross-reactive allergens by using murine model of OAS and protein microarray technology. We focused on lip angioedema, which is one of the most common symptoms of OAS, and confirmed that mast cells reside in the tissues inside the lower lip of the mice. Interestingly, when the food allergen ovalbumin (OVA) was injected inside the lower lip of mice with high levels of OVA-specific IgE followed by an intravenous injection of the Evans blue dye, we found immediate dye extravasation in the skin of the neck in a mast cell-dependent manner. In addition, the degree of mast cell degranulation in the oral cavity, reflecting the severity of oral allergic responses, can be estimated by measuring the amount of extravasated dye in the skin. Therefore, we used this model of OAS to examine IgE cross-reactive allergens in vivo. Protein microarray analysis showed that serum IgE from mice intraperitoneally sensitized with ragweed pollen, one of the major pollens causing pollinosis, bound highly to protein extracts from several edible plants including black peppercorn and fennel. We confirmed that the levels of black pepper-specific IgE and fennel-specific IgE were significantly higher in the serum from ragweed pollen-sensitized mice than in the serum from non-sensitized control mice. Importantly, analysis of murine model of OAS showed that the injection of black pepper or fennel extract induced apparent oral allergic responses in ragweed pollen-sensitized mice. These results indicate IgE cross-reactivity of ragweed pollen with black pepper and fennel. In conclusion, we developed mouse model of OAS to identify IgE cross-reactive pollen and food allergens, which will help understand the pathogenesis of OAS/PFAS.

Cross-reactivity of each fraction among cereals in children with wheat allergy

BACKGROUND

Cross-reactivity between wheat and other cereals is a crucial issue in the management of wheat allergy. Few studies have reported in vitro cross-reactivity in immediate-type wheat allergy. The aim of this study aimed to examine cross-reactivity of the three fractions (albumin/globulin, gliadin, and glutenin fractions) among cereals in children with wheat allergy.

METHODS

Sera from 128 children with immediate-type wheat allergy were collected. Specific immunoglobulin E (sIgE) levels against each fraction of wheat, barley, and rye were measured by enzyme-linked immunosorbent assay (ELISA). Cross-reactivities of each fraction among wheat, barley, and rye were examined via inhibition ELISA.

RESULTS

All subjects were sensitized to all fractions of wheat, barley, and rye. The wheat sIgE levels were significantly higher than those of barley and rye in all the fractions (p ≤ .001) and were significantly correlated with sIgE levels in each fraction (r = .887-.969, p < .001). Inhibition ELISA revealed that wheat inhibited the IgE binding to most of the solid phases at lower protein levels compared with barley and rye in all fractions.

CONCLUSIONS

In children with immediate-type wheat allergy, sensitization to all the three fractions of wheat was observed. In addition, they showed sensitization to barley and rye caused by in vitro cross-reactivity with wheat in each fraction. When managing children with wheat allergy, sensitization to barley and rye caused by the cross-reactivities should be considered.

Structure And Biological Functions Of Milk Caseins

Caseins, which are contained in milk, play a significant role in the development of clinical symptoms of allergic reactions in adults and children. To date, the properties of caseins have been studied, their primary structure has been identified. However, despite available scientific reviews and original articles, an issue of the structural organization of milk casein micelles and their biological functions is still very controversial. In this regard, the proposed review is relevant, since it most fully reflects current information about various types of caseins, their physicochemical and immunobiological properties, and analyzes in detail the existing theories on the structural organization of casein micelles. Of particular interest in our review are the data on the comparative analysis of the structure and properties of caseins in both human breast milk and cow’s milk, as well as the section dealing with the allergenic activity of cow’s milk caseins and their cross-reactivity with milk proteins of other mammalian species. The objective of this review is to summarize current data on the structure and properties of casein proteins, and to determine their role in the formation of sensitization to dairy products.

Nip allergies in the Bub: a qualitative study for a public health approach to infant feeding for allergy prevention

OBJECTIVE

To identify a brand, key messages and resources to underpin a public health approach to food allergy prevention.

METHODS

A focus group design was used to explore perceptions and opinions of potential brands, infant feeding messages and resources for providing standardised food allergy prevention information. Focus groups were conducted in February 2018 using interview guides and were transcribed verbatim. A content analysis of the transcripts was undertaken using thematic analysis software. The University of Western Australia provided ethics approval: RA/4/20/4280.

RESULTS

Seven focus groups with 39 participants were conducted. Four slogans and styles of imagery were considered. 'Nip Allergies in the Bub' was the most favoured slogan and images of babies with food were most favoured. Participant feedback was sought regarding messages and supporting messages were considered important. Participants were consulted about useful resources and a website was identified.

CONCLUSIONS

Conducting focus groups assisted the selection of a brand, messages and resources to underpin a public health approach to implementing allergy prevention guidelines.

IMPLICATIONS FOR PUBLIC HEALTH

This is the first focus group research undertaken for food allergy prevention. Identification of a meaningful brand, key messages and resources will support a public health approach to implementing allergy prevention guidelines.

Evaluation of early laryngeal reaction at oral food challenge

Background

Open oral food challenge (OFC) is a commonly used diagnostic method for food allergy; however, the occurrence of uncertain reactions leads to inconclusive results.

Objective

We aimed to determine the associations between mild laryngeal symptoms and positive results in open OFCs.

Methods

We retrospectively investigated medical records of high-risk children (aged 3-15 years) who had undergone open OFC for a low dose of peanuts, hen's egg, cow's milk, or wheat. The OFC result, severity of allergic reactions, and administered treatments during OFCs were compared between the subjects with and without laryngeal symptoms. The risks of a positive OFC result were assessed by using logistic univariate and multivariate analyses, with age, sex, and serum levels of total and food-specific IgE as covariates.

Results

Among the 198 patients who underwent OFC, 25 had mild laryngeal symptoms: 8 (32%), 7 (22%), 0 (0%), and 10 (40%) in the OFC trials with hen's egg, cow's milk, wheat, and peanuts, respectively. In the peanut OFCs, univariate analyses revealed a 5-fold higher risk of a positive result (odds ratio = 5.0 [95% CI = 1.1-22.8]) in the symptomatic subjects than in the asymptomatic subjects. However, on multivariate analyses, none of the associations between the symptoms and a positive result were significant in any of the OFCs. The occurrence of anaphylaxis and adrenalin injections did not differ significantly between the symptomatic and asymptomatic subjects.

Conclusions

Laryngeal symptoms should be considered a warning sign for a positive OFC result in peanut OFCs, although not critical enough to stop the challenge.

Effects of delivery mode and labor duration on the development of food sensitization in infancy

BACKGROUND

The effects of delivery mode and labor duration on the development of food sensitization (FS) in infancy remain unclear.

OBJECTIVE

To elucidate the potential effects of delivery mode and labor duration on FS development by 6 months of age.

METHODS

Using data from a randomized controlled trial of a birth cohort from 4 Japanese hospitals that assessed cow's milk allergy development by 6 months of age, we performed a nested case-control trial of 462 participants who had undergone the final assessment at 6 months of age. FS was defined as positive skin prick test reactions to hen's egg, cow's milk, wheat, or soy. For the primary outcome, we calculated the adjusted odds ratio of vaginal delivery (VD) relative to cesarean delivery for FS development by 6 months of age using a multivariable logistic regression analysis. For the secondary outcome, we compared labor durations between participants with and without FS using the Mann-Whitney U test.

RESULTS

The adjusted odds ratio of VD for FS development was 2.54 (95% confidence interval, 1.32-4.87; P = .005). The median labor duration was significantly longer in participants with FS (5.7 hours, interquartile range, 2.7-10.1) than in participants without FS (4.5 hours, 1.1-8.2) (P = .01).

CONCLUSION

VD was considerably associated with an increased risk of FS in infancy, and longer labor durations may promote FS development.

Oropharyngeal symptoms without systemic reactions as a risk factor for food allergen intolerance: a longitudinal pediatric study

Background

The determinants of tolerance to food allergens are not fully understood. We aimed to elucidate the longitudinal association between oropharyngeal symptoms without systemic reactions (OSw/oS) and tolerance to food allergens.

Methods

We included all patients diagnosed with single food allergy to egg (n = 121), milk (n = 55), and wheat (n = 41) using the oral food challenge test (OFC) from 2014 to 2017. These patients received oral immunotherapy at home and/or in the hospital after diagnosis by OFC. We compared the incidence proportion of tolerance within 2 years by OSw/oS and other variables for 217 patients with food allergy. We defined OSw/oS as isolated symptoms of oropharyngeal discomfort that occurred after ingestion of a safe dose of the allergenic food determined by the OFC in the first 6 months.

Results

Of the 217 patients (median age 37.5 months, male 64.5%), 53 developed OSw/oS (24.4%), and 151 (egg, 85 milk, 36 and wheat, 30) attained tolerance in 2 years. Patients without OSw/oS showed a significantly higher incidence of tolerance than those with the symptoms (crude hazard ratio [HR] 5.62, 95% confidence interval [CI] 3.58–8.82, p < 0.001). The association was consistently significant in the multivariable model (adjusted HR 9.50, 95% CI 5.25–17.20, p < 0.001) independent of other risk factors for intolerance, such as concomitant bronchial asthma (adjusted HR 3.33), history of anaphylaxis (adjusted HR 2.16), milk allergy (adjusted HR 2.02), and allergic symptoms with low dose OFC (adjusted HR 1.52).

Conclusion

Our results suggest that OSw/oS may be a risk factor for intolerance to food allergens. To reveal a high risk of food allergen intolerance may help patients and their families as well as healthcare professionals prepare for the challenge of continuing oral immunotherapy.

Protease-digested egg-white products induce oral tolerance in mice but elicit little IgE production upon epicutaneous exposure

BACKGROUND

Early food introduction induces tolerance, but epicutaneous exposure, especially via eczema lesions, promotes IgE sensitization. Aiming for safe and effective primary prevention of egg allergy, we examined several protease-digested egg-white (EW) products for three properties: 1) induction of oral tolerance that prevents IgE sensitization, 2) weak IgE binding that can prevent allergic reactions even in IgE-sensitized mice, and 3) minimal epicutaneous IgE sensitization even when in contact with inflamed skin.

METHODS

Heated EW was digested with several proteases under optimal conditions. First, three-week-old BALB/c female mice were intragastrically administered EW or each protease-digested EW product, followed by intraperitoneal ovalbumin (OVA) or ovomucoid (OVM) injection with alum. Serum OVA- and OVM-specific IgE titers were measured. Second, six-week-old mice were sensitized with OVA/OVM, and the rectal temperature was measured after intraperitoneal administration of EW or each protease-digested EW. Third, EW or each protease-digested EW product was applied to the tape-stripped skin for 3 days/week for 3 weeks. Serum OVA- and OVM-specific IgE titers were measured.

RESULTS

Orally administered pepsin-digested EW product (PDEW) and Thermoase PC10F-digested EW product (TDEW) significantly suppressed OVA-/OVM-specific IgE production. Neither product elicited a body temperature decline (anaphylaxis) in OVA-/OVM-sensitized mice. Serum OVA-/OVM-specific IgE levels were significantly lower in mice epicutaneously exposed to PDEW or TDEW than in EW-exposed mice.

CONCLUSIONS

Two protease-digested EWs showed potential as optimal EW products for early introduction for primary prevention of egg allergy.

Fish Roe-Induced Anaphylaxis in Italy: A Pediatric Case Report

Fish roe are not yet described as triggers of allergic reactions in Italy, especially during the pediatric age; they are more frequently involved in anaphylaxis in Eastern countries, such as Japan. For this report, we reported a case of anaphylaxis in a 2-year-old boy admitted to our Hospital Pediatric Emergency Room with a suspected allergic reaction. 15 min after the meal, he presented generalized urticaria, angioedema, wheezing, sneezing, and two vomiting episodes. The meal was smoked salmon, butter, mayonnaise, anchovies, and fish roe (salmon and lumpfish roe). Tryptase serum levels presented as elevated in the acute phase and normal after 24 h. Serum food-specific IgE tested negative for salmon and other fish, such as skin prick tests. Serum food-specific IgE showed that the patient was sensitized to cow's milk and eggs, but he doesn't have a food allergy. He had regularly consumed milk and eggs before and after the allergic reaction without clinical problems. A prick-by-prick test resulted positive for fish roe (salmon and lumpfish roe). Based on patient's history, allergy test results in vivo, and tryptase serum levels, the diagnosis of anaphylaxis induced by fish roe was confirmed. In conclusion, to the best of our knowledge, this is the first pediatric case of fish roe-induced anaphylaxis reported in Italy.

Egg Reintroduction Following Oral Food Challenge in Japanese Children

Background: Oral food challenge (OFC) is the most reliable method for diagnosing food allergies. However, the scarcity of long-term data on eating habits of people after a negative OFC poses a challenge for provisional medical care.

Objective: This study was performed to investigate the percentage of people who could reintroduce eggs into their diet several years after an OFC.

Methods: Study participants included 0–6-year-old children with negative results from an OFC using one egg as the food allergen, boiled for 20 min, from January 2012–March 2017, 1–3 years after the OFC.

Results: A total of 72 subjects were analyzed, out of which 52 were males (72.2%). The median age (range) was 20 months (16–32.3), and the median age (range) at the first OFC was 15 months (12.8–23.3). Eggs were reintroduced in 62 cases (86.1%), while 10 cases (13.9%) did not undergo any diet change. The adjusted odds ratio (OR, 95% CI), with post-OFC to pre-OFC anxiety ≥ 0.2, was 9.4 (1.0–86), p = 0.04; OR for allergic symptoms that occurred post-OFC was 2.2 (0.45–11), p = 0.34; OR for initial OFC at an age of ≥15 months was 3.2 (0.54–19), p = 0.2; and OR for the history of anaphylaxis from eggs was 0.17 (0.02–1.5), p = 0.11.

Conclusion: Most cases reintroduced eggs after an OFC. However, reintroduction did not occur in some cases, which was associated with greater anxiety among caregivers post-OFC. If the caregiver's anxiety is intense, it is necessary to provide psychological intervention and dietary guidance when reintroducing eggs at home after an OFC and to follow-up outpatient long-term progress.

A 60-minute dosing interval is safer than a 30- or 40-minute interval in oral food challenge

BACKGROUND

The interval between antigen ingestion may influence the safety of oral food challenge tests (OFCs), especially in patients with severe food allergies.

METHODS

This retrospective chart review of OFCs eliciting objective reactions to wheat, egg, and milk that were performed between April 2012 and January 2021 evaluated an equivalent number of low-dose OFCs performed at 30-, 40-, or 60-min intervals. To avoid the influence of the potential allergy severity of the patients, the prediction scores of all intervals were matched. We evaluated the total symptom score (TS), total ingested dose, and the proportions of severe reactions (TS ≥ 30) and adrenaline use.

RESULTS

We analyzed 945 OFCs (wheat, n = 186; egg, n = 561; milk, n = 198). The 60-min OFC had significantly lower TS than the 30- and 40-min OFC methods in wheat (p < 0.001 and p = 0.003, respectively), egg (p < 0.001 for both), and milk (p < 0.001 and p = 0.018, respectively). The total dose in the 60-min method was significantly lower than in the 30-min method (p < 0.001 for all). The proportion of severe reaction (TS ≥ 30) in the 60-min method was significantly lower than that in the 30-min method for the egg and milk OFCs (p = 0.001 and p < 0.001, respectively). There was no difference in the rates of adrenaline injection.

CONCLUSIONS

The 60-min interval is safer than 30- or 40-min intervals in wheat, egg, and milk OFCs in patients with a low threshold dose for food allergy.

Early Introduction of Multi-Allergen Mixture for Prevention of Food Allergy: Pilot Study

The incidence and prevalence of food allergy (FA) is increasing. While several studies have established the safety and efficacy of early introduction of single allergens in infants for the prevention of FA, the exact dose, frequency, and number of allergens that can be safely introduced to infants, particularly in those at high or low risk of atopy, are still unclear. This 1-year pilot study evaluated the safety of the early introduction of single foods (milk, egg, or peanut) vs. two foods (milk/egg, egg/peanut, milk/peanut) vs. multiple foods (milk/egg/peanut/cashew/almond/shrimp/walnut/wheat/salmon/hazelnut at low, medium, or high doses) vs. no early introduction in 180 infants between 4-6 months of age. At the end of the study, they were evaluated for plasma biomarkers associated with food reactivity via standardized blood tests. Two to four years after the start of the study, participants were evaluated by standardized food challenges. The serving sizes for the single, double, and low dose mixtures were 300 mg total protein per day. The serving sizes for the medium and high dose mixtures were 900 mg and 3000 mg total protein, respectively. Equal parts of each protein were used for double or mixture foods. All infants were breastfed until at least six months of age. The results demonstrate that infants at either high or low risk for atopy were able to tolerate the early introduction of multiple allergenic foods with no increases in any safety issues, including eczema, FA, or food protein induced enterocolitis. The mixtures of foods at either low, medium, or high doses demonstrated trends for improvement in food challenge reactivity and plasma biomarkers compared to single and double food introductions. The results of this study suggest that the early introduction of foods, particularly simultaneous mixtures of many allergenic foods, may be safe and efficacious for preventing FA and can occur safely. These results need to be confirmed by larger randomized controlled studies.

Development of allergic rhinitis in early life: A prospective cohort study in high-risk infants

BACKGROUND

Allergic rhinitis (AR) is the most common allergic disease in children. The development process of AR in early childhood, however, is not well understood. We prospectively investigated the process in regard to not only the nasal symptoms and sensitization but also the nasal cytology, in relation to recurrent wheeze in a high-risk cohort.

METHODS

Infants under 2 years of age with atopic dermatitis (AD) and/or food allergy (FA) symptoms were recruited and followed prospectively for 2 years. The phenotype of perennial AR was classified based on the presence/absence of (1) persistent nasal symptoms, (2) nasal eosinophils, and (3) HDM sensitization, the most common allergen for perennial AR in Japan. AR-like phenotypes were defined as positive for at least two of those three categories. High-risk recurrent wheezer was diagnosed based on the Japanese guidelines and Global Initiative for Asthma. Cox proportional hazards regression analyses for high-risk recurrent wheeze and the AR-like phenotype, adjusting for known covariate risk factors for asthma.

RESULTS

A total of 299 children were enrolled, and 237 subjects (78%) completed the 2-year observation. The prevalence of eosinophilia in nasal secretions increased from 18.5% to 69.9%, while HDM-specific IgE ≥ 0.35 kU_A /L increased from 30.6% to 74.8%. AR-like phenotypes increased from 18.4% to 65.0%. The AR-like phenotype at 2 years was associated with development of high-risk recurrent wheezer (HR 2.062; 95% CI 1.005-4.796).

CONCLUSIONS

The prevalence of an HDM-related AR-like phenotype was markedly increased during infancy in infants with AD/FA and was associated with high-risk recurrent wheezer.

Relationship of food allergy with quality of life and sleep in psychiatric patients

AIM

Few studies have examined the relationship between food allergy (FA) and psychiatric disorders. We aimed to examine the possible relationship of FA with quality of life (QOL) and sleep in adult patients with psychiatric disorders.

METHODS

Of the 812 participants (451 females, mean age: 42.7 ± 11.3 years), 430 had schizophrenia/schizoaffective disorder, 106 had depression, 124 had bipolar disorder, 40 had anxiety disorders, 38 had developmental disorders, and 11 had eating disorders; 63 were other cases. We documented FA and sleep disturbance via a questionnaire. QOL was assessed with the Medical Outcomes Study 8-Item Short-Form Health Survey (SF-8 Japanese version).

RESULTS

There were 126 patients (15.5%) reporting FA. SF-8 physical component summary (PCS) and mental component summary (MCS) scores were both significantly lower among individuals with FA than those without. Moreover, PCS and MCS scores decreased as the number of allergens increased. Sleep disturbance was common among patients (76.0%). The proportions of individuals with sleep disturbance and nocturnal awakening were significantly higher in the group with FA, with the proportions increasing with higher number of allergens.

CONCLUSION

We obtained the first evidence that FA is associated with impaired QOL and sleep in psychiatric patients, which can be improved by avoiding exposure to food allergens.

Inter-laboratory comparison of semiquantitative allergen-specific Immunoglobulin E test: 7 years of experience in Korea

INTRODUCTION

Multiple allergen simultaneous test (MAST) is widely used as a screening tool for allergic diseases and has the advantage of providing specific IgE (sIgE) results for various allergens in semiquantitative class. We have continuously conducted external quality assessment (EQA) since 2012 for clinical laboratories performing MAST using AdvanSure allergy screen test (LG CHEM, Korea). This study provides an account of the EQA experience.

METHODS

Samples were prepared using pooled sera collected from patients with suspected allergic disease and sent to each laboratory twice a year. Each round included 4-6 serum samples with sIgE for 10-20 inhaled or food allergens. The acceptable class value was the most frequently reported MAST class ±1 titer that exceeded 80% of the total laboratory results.

RESULTS

The average number of participating laboratories was 76 (49-90) and the average response rate was 97.3% during the entire survey period. The acceptable rates were consistently high at 97.7% ± 3.7%. Of the total 537 trials, 18 trials (3.4%) were regarded as nonconsensus results, in which acceptable answers did not exceed 80%. For unacceptable results, the false-negative rate (1.5% ± 2.8%) was higher than the false-positive rate (0.8% ± 2.7%) (p < 0.001). MAST class results were correlated with quantitative IgE results by ImmunoCAP (Spearman's correlation coefficient of 0.682 (p < 0.001) and gamma index of 0.777 (p < 0.001).

CONCLUSION

Although EQA for MAST showed a high level of acceptable answer, some allergen assays require harmonization. Continuous performance of systematic EQA is needed to improve the accuracy of sIgE assays and quality control in clinical laboratories.

Association of egg protein levels in dust with allergy status and related factors

BACKGROUND

Levels of peanut protein in dust have been reported to be associated with sensitization and allergy to it, so controlling food protein in dust may help prevent food allergy. However, studies of factors associated with egg protein levels in dust are scarce. This study aimed to determine the factors contributing to egg protein levels in dust.

METHODS

This cross-sectional study included 159 participants in the Sub-Cohort Study of the Japan Environment and Children's Study in Yamanashi Prefecture at a 6 year follow up. House dust at 6 years was collected and egg protein concentrations were measured for whole egg protein. Household factors, including the maternal frequency of egg consumption, were assessed by questionnaires. A linear regression model was used to analyze the effect of household environmental factors on egg protein in dust.

RESULTS

In multivariate analysis, frequent maternal egg consumption (≥5 times a week) was associated with higher egg protein concentrations in house dust (β = 0.96, P = 0.01). The egg protein load was significantly associated with a higher number of cohabitants (≥5, β = 0.85, P = 0.02) in addition to frequent maternal egg consumption. Among the participants, 140 (88.1%) had no egg allergy, 15 (9.4%) were egg tolerant, and 4 (2.5%) had an egg allergy at 6 years old. There was no significant association between the current egg allergy status and egg protein concentrations in dust.

CONCLUSIONS

The frequency of maternal egg consumption and the number of inhabitants are contributing factors to egg protein levels in dust.

Elemental diet therapy for eosinophilic gastroenteritis and dietary habits

BACKGROUND

Eosinophilic gastrointestinal disorders (EGID) are a group of conditions with increased eosinophilic infiltration in any part of the gastrointestinal tract. Although an allergic reaction to certain foods is considered the main cause of EGID, their detailed pathomechanism has not yet been elucidated, nor have proper management strategies been fully established. Moreover, some patients with intractable EGID are resistant to such therapies as an empirical elimination diet and corticosteroids.

METHODS

We analyzed retrospectively the medical records of four children with intractable eosinophilic gastroenteritis (EGE) managed with elemental diet therapy (EDT) using an amino acid-based formula.

RESULTS

All patients displayed resolution of their symptoms after 2 weeks of EDT. Three patients successfully completed food reintroduction and could return to their normal life. No adverse events related to EDT were recorded.

CONCLUSIONS

Elemental diet therapy appears effective and safe for treating pediatric intractable EGE symptoms. Afterwards, the patient's dietary habits should be considered during carefully monitored food reintroduction. With the relatively small number of published case reports and no randomized trials, more study is needed on EDT for EGE.

Subtypes of atopic dermatitis: From phenotype to endotype

Atopic dermatitis (AD) is a heterogenous disorder and can be classified into different types. Stratification of subtypes may enable personalized medicine approaches. AD can be categorized into the IgE-high, extrinsic subtype and the IgE-normal, intrinsic subtype. While extrinsic AD is the major subtype possessing skin barrier impairment (high incidence of filaggrin mutations), intrinsic AD occupies about 20% of AD with female dominance and preserved barrier. Extrinsic AD exhibits protein allergy and food allergy, but intrinsic AD shows metal allergy possibly in association with suprabasin deficiency. In particular, accumulated knowledge of food allergy has more clearly characterized extrinsic AD. European American (EA) and Asian AD subtypes have been also proposed. Asian patients with AD are characterized by a unique blended immune dysregulation and barrier feature phenotype between EA patients with AD and those with psoriasis. In another ethnic study, filaggrin loss-of-function mutations are not prevalent in African American patients with AD, and Th1/Th17 attenuation and Th2/Th22 skewing were seen in these patients. Recent endotype classification provides new insights for AD and other allergic disorders. Endotype is defined as the molecular mechanisms underlying the visible features/phenotype. Endotype repertoire harbors activation of type 2 cytokines, type 1 cytokines, and IL-17/IL-22, impairment of epidermal barrier, and abnormalities of intercellular lipids. Classification of endotype has been attempted with serum markers. These lines of evidence indicate a need for personalized or precision medicine appropriate for each subtype of AD.

Food allergy across the globe

The prevalence of food allergy (FA) is increasing in some areas of the globe, highlighting the need for better strategies for prevention, diagnosis, and therapy. In the last few decades, we have made great strides in understanding the causes and mechanisms underlying FAs, prompting guideline updates. Earlier guidelines recommended avoidance of common food allergens during pregnancy and lactation and delaying the introduction of allergenic foods in children aged between 1 and 3 years. Recent guidelines for allergy prevention recommend consumption of a healthy and diverse diet without eliminating or increasing the consumption of allergenic foods during pregnancy or breast-feeding. Early introduction of allergenic foods is recommended by most guidelines for allergy prevention after a period of exclusive breast-feedng (6 months [World Health Organization] or 4 months [European Academy of Allergy and Clinical Immunology]). New diagnostics for FA have been developed with varied availability of these tests in different countries. Finally, the first oral immunotherapy drug for FA was approved by the US Food and Drug Administration and European Medicines Agency in 2020. In this review, we will address the global prevalence of FA, our current understanding of the causes of FA, and the latest guidelines for preventing, diagnosing, and treating FA. We will also discuss similarities and differences between FA guidelines.

Increased corn oil intake during an allergy sensitization period aggravates food allergy severity after oral allergen exposure

Egg white (EW) allergy model mice underwent 15-day oral immunotherapy (OIT) using diets with different corn-oil content and 1% EW. After OIT, mortality following an oral food challenge in OIT groups was approximately 90%. However, in previous studies, mortality was 0%. This phenomenon is to be associated with increased corn-oil intake during allergy sensitization and allergen exposure for 2 weeks.

Comprehensive hospital-based regional survey of anaphylaxis in Japanese children: Time trends of triggers and adrenaline use

BACKGROUND

Since few studies have analyzed time trends in pediatric anaphylaxis, including triggers and adrenaline usage, this study aimed to reveal these issues in a comprehensive analysis of pediatric anaphylaxis cases.

METHODS

The Aichi Medical Association performed a comprehensive survey of pediatric anaphylaxis cases aged under 15 years from 87 secondary and 25 tertiary emergency care hospitals in Aichi Prefecture (population 7.5 million), Japan.

RESULTS

Between April 2016 and March 2020, 3423 cases of anaphylaxis were identified. Food items were the most frequent trigger (73%), followed by exercise after food ingestion (4.3%), and drugs (2.2%). Egg (19%) and milk (17%) specifically were the most frequent among food triggers, while the largest proportional increase was observed in tree nuts from 6.0% in 2017 to 15% in 2019. Overall, 1647 (48%) cases were admitted to the hospital, of which 26 (0.8%) were admitted to the intensive care unit. Drug-induced anaphylaxis was associated with the highest admission rate (71%). Of the 2493 food-induced anaphylaxis cases, 1107 (44%) were treated with adrenaline. Among them, 343 cases included previously prescribed adrenaline auto-injectors (AAI), with 225 (66%) usages prior to hospital arrival. There was no significant difference in the admission rate between the cases in which AAIs were used and those with adrenaline administered in the hospital (68% and 72%, respectively).

CONCLUSIONS

The proportion of tree nuts in food-induced anaphylaxis increased significantly. Although prehospital AAI use has become widespread, it was not associated with lower admission rate compared to in-hospital adrenaline usage.

Factors associated with outcome of egg allergy 1 year after oral food challenge: A good baseline quality of life may be beneficial

BACKGROUND

Safely liberalizing the diet to include an allergenic food may accelerate resolution of food allergy. The outcome of liberalization, however, varies among patients.

METHODS

We conducted a prospective observational study to identify factors associated with outcome for egg allergy 1 year after oral food challenge (OFC). We enrolled children <72 months old who had egg allergy and underwent OFC for determination of the safe intake quantity of egg allergen. Each child's baseline clinical background was recorded. Caregivers used the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) to assess their children's QoL. Dietary advice based on the OFC result was provided to support safe egg consumption. At 1 year after OFC, the quantity of egg each child safely consumed in daily life was surveyed. We classified the outcome as Successful (Group S) if the quantity increased during the 1 year, or as Unsuccessful (Group U) if it did not. Factors associated with the outcome were investigated by multivariate logistic regression analysis.

RESULTS

A total of 93 children were enrolled, and after 1 year, 57 finished in Group S and 36 in Group U. The mean FAQLQ-PF score at baseline was significantly lower (ie, a better QoL) in Group S than in Group U. Multivariate logistic regression analysis identified a good QoL and absence of comorbid asthma or atopic dermatitis as factors predicting a favorable outcome.

CONCLUSION

QoL may affect food allergy outcome. Intervention focusing on the QoL may promote outgrowing of food allergies.

Clinical Manifestations of Pediatric Food Allergy: a Contemporary Review

Food allergies (FAs) are an emerging health care issue, and a "second wave of the allergy epidemic" was named. There are extensive data that documented the prevalence rate as high as approximately 10%. FAs are immunological adverse reactions, including IgE-mediated mechanisms, cell-mediated mechanisms, or mixed IgE- and cell-mediated mechanisms. A diagnosis of FA is made by specific symptoms encounter with food, detailed past history, sensitization tests, and oral food challenges (OFCs) if necessary. The component-resolved diagnostics (CRD) test can distinguish true or cross-reaction. "Minimal elimination" from the results of CRD and OFC could avoid unnecessary food restriction. Strict food limitation is harsh and stressful on patients and their families. Children with FAs experience a higher rate of post-traumatic stress symptoms (PTSS) and bullying than others. In the last 20 years, oral immunotherapy (OIT), sublingual immunotherapy (SLIT), and epicutaneous immunotherapy (EPIT) are treatment strategies. OIT and EPIT are the most two encouraging treatments for FA. This review aims to introduce FAs in diverse clinical disorders, new perspectives, and their practical implications in diagnosing and treating FA.