Two-step egg introduction for prevention of egg allergy in high-risk infants with eczema (PETIT): a randomised, double-blind, placebo-controlled trial

Oral Immunotherapy: An Overview

Oral immunotherapy (OIT) is an alternative treatment of IgE-mediated food allergy that has been shown to increase tolerance threshold to many of the top food allergens, although this effect may be dependent on age, dose, frequency, and duration. OIT has been shown to be effective and safe in infants, and early initiation can improve rates of desensitization even for those foods whose natural history favors loss of allergy. Studies looking at protocol modification to improve OIT success are ongoing as is the evaluation of clinical tools to help monitor OIT effects.

Management of Infant Atopic Eczema to Prevent Severe Eczema and Food Allergy

Early intervention and active management of infant atopic eczema may play a crucial role in limiting eczema severity and preventing the onset of immediate-type food allergy. Eczema management involves education, skincare and medications targeting skin inflammation and barrier repair. Topical corticosteroids are the mainstay of anti-inflammatory therapy, with nonsteroidal options available for some infants. Proactive therapy, addressing subclinical inflammation, is useful for preventing eczema flares, especially in infants with recurrent eczema flares despite reactive therapy. In clinical practice, holistic consideration of overall infant and family health is essential. Providing advice on maternal stress management, nutritional guidance and recommendations for proper sleep and lifestyle is crucial for the well-being of children and their families, not limited to eczema treatment alone.

Regular consumption following early introduction of allergenic foods and aggressive treatment of eczema are necessary for preventing the development of food allergy in children

PURPOSE OF REVIEW

Over the past two decades, food allergy prevention strategies have shifted from 'delayed introduction' to 'no delayed introduction' to 'early introduction' of allergenic foods. This article reviews important research in this field published in the early 2020s to support future strategies for food allergy prevention.

RECENT FINDINGS

Recent randomized controlled trials (RCTs), systematic reviews, meta-analyses, and real-world studies have reported that early allergenic food introduction, especially peanut and egg, are effective for preventing food allergies. However, there are also reports that food-induced anaphylaxis admission rates in infants are increasing.

SUMMARY

Early allergenic food introduction by itself is not sufficient to prevent the development of food allergies. Recent RCTs (SPADE study and COMEET study) have demonstrated that continued regular cow's milk consumption after early introduction is important for preventing the onset of cow's milk allergy. Furthermore, an RCT (PACI study) reported that early and aggressive anti-inflammatory topical therapy for eczema can contribute to the prevention of egg allergy by suppressing percutaneous sensitization. Food allergies may be prevented through a combination of early food introduction, regular consumption, and active eczema treatment. Further research is needed to develop well tolerated, effective, and practical strategies to prevent food allergies.

Maternal and Infant Dietary Patterns Are Not Related to Food Allergy Risk in Singapore Children: GUSTO Cohort Study

BACKGROUND

We previously reported that delayed allergenic food introduction in infancy did not increase food allergy risk until age 4 y within our prospective cohort. However, it remains unclear whether other aspects of maternal or infant diet play roles in the development of childhood food allergy.

OBJECTIVES

We examined the relationship between maternal pregnancy and infant dietary patterns and the development of food allergies until age 8 y.

METHODS

Among 1152 Singapore Growing Up in Singapore Towards healthy Outcomes study mother-infant dyads, the infant's diet was ascertained using food frequency questionnaires at 18 mo. Maternal dietary patterns during pregnancy were derived from 24-h diet recalls. Food allergy was determined through interviewer-administered questionnaires at regular time points from infancy to age 8 y and defined as a positive history of allergic reactions, alongside skin prick tests at 18 mo, 3, 5, and 8 y.

RESULTS

Food allergy prevalence was 2.5% (22/883) at 12 mo and generally decreased over time by 8 y (1.9%; 14/736). Higher maternal dietary quality was associated with increased risk of food allergy (P ≤ 0.016); however, odds ratios were modest. Offspring food allergy risk ≤8 y showed no associations with measures of infant diet including timing of solids/food introduction (adjusted odds ratio [aOR]: 0.90; 95% confidence interval [CI]: 0.42, 1.92), infant's diet quality (aOR: 0.93; 95% CI: 0.88, 0.99) or diet diversity (aOR: 0.84; 95% CI: 0.6, 1.19). Most infants (89%) were first introduced to cow milk protein within the first month of life, while egg and peanut introduction were delayed (58.3% introduced by mean age 8.8 mo and 59.8% by mean age 18.1 mo, respectively).

CONCLUSIONS

Apart from maternal diet quality showing a modest association, infant's allergenic food introduction, diet quality, and dietary diversity were not associated with food allergy development in this Asian pediatric population. Interventional studies are needed to evaluate the efficacy of these approaches to food allergy prevention across different populations.

Tolerance induction through early feeding to prevent food allergy in infants and children with sensitization against food allergens (TIFFANI): rationale, study design, and methods of a randomized controlled trial

BACKGROUND

Children with sensitization against foods have to be orally food-challenged before eating these foods for the first time. However, the waiting time for an oral food challenge (OFC) in Germany is about 3-6 months. In contrast, there are hints that an early introduction of allergenic foods might be protective regarding the development of food allergy. The aim of this clinical trial is therefore to investigate, whether an introduction and regular consumption of small amounts of food allergens is safe and will result in an increase of tolerance in children with sensitization against food allergens with unknown clinical relevance.

METHODS

In this randomized, placebo-controlled, double-blind, single-center trial, 138 children (8 months to 4 years of age) sensitized to the target allergen(s) hen's egg, cow's milk, peanuts, and/or hazelnuts with unknown clinical relevance will be randomized in a 1:1 ratio to either an active or a placebo group, daily receiving a rusk-like biscuit powder with or without the target allergen(s) for 3-6 months until an OFC will be performed in routine diagnostics. The primary endpoint is an IgE-mediated food allergy to the primary target allergen, after the interventional period.

DISCUSSION

Children with sensitization against food allergens with unknown clinical relevance often have to avoid the corresponding foods for several months until an OFC is performed. Therefore, the "window of opportunity" for an early preventive introduction of allergenic foods might be missed. This trial will assess whether an introduction of small allergen amounts will favor tolerance development in these children.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00032769. Registered on 02 October 2023.

Introduction of allergenic food to infants and allergic and autoimmune conditions: a systematic review and meta-analysis

OBJECTIVES

To evaluate the effects of early introduction to allergenic foods compared with late introduction and its impact on food allergy, food sensitisation and autoimmune disease risk.

DESIGN AND SETTING

The systematic review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Four electronic databases (MEDLINE, CENTRAL, EMBASE and CINAHL) were searched from inception till 24 October 2022 using keywords and MeSH without limitations on publication's language or date. A forward and backwards citation analysis was also conducted. Risk of bias was assessed by three authors independently, in pairs using the Cochrane Risk of Bias Tool 2. Findings were narratively and quantitatively synthesised. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.

PARTICIPANTS

Randomised controlled trials (RCTs) on allergenic food introduction prior to 12 months of age that evaluated its effect on the development of allergic and autoimmune conditions.

INTERVENTION

Early introduction to allergenic foods to infants diet.

MAIN OUTCOME MEASURES

(1) Food allergy and sensitisation with main measures including oral food challenge, specific-IgE, skin prick testing, physician assessment and parental reporting. (2) Allergic and autoimmune conditions such as asthma and eczema.

RESULTS

Of the 9060 identified records, we included 12 RCTs. We found high to moderate certainty evidence suggested that early introduction of allergen-containing foods reduces the risk of multiple food allergies (4 RCTs, 3854 participants, RR 0.49, 95% CI 0.33 to 0.74), egg (8 RCTs, 5193 participants, RR 0.58, 95% CI 0.44 to 0.78), peanut (3 RCTs, 4183 participants, RR 0.31, 95% CI 0.17 to 0.54) and atopic dermatitis or eczema (4 RCTs, 3579 participants, RR 0.88, 95% CI 0.78 to 1.00). Effects on other food allergies including milk, wheat, fish; autoimmune conditions, and food sensitisation are very uncertain and informed by low and very-low certainty evidence. No important subgroup differences were observed related to baseline risk of allergy and age at introduction. Sensitivity analyses limited to low risk of bias RCTs showed similar results.

CONCLUSIONS

This systematic review and meta-analysis shows that early introduction of allergen-containing food from 4 to 12 months of age, was associated with lower risk of multiple food allergy and eczema. Further research on other allergenic foods, and their long-term impact on food allergy and autoimmune risk is essential for enhancing our understanding on development of these conditions and guiding future clinical recommendations.

PROSPERO REGISTRATION NUMBER

CRD42022375679.

Complementary Feeding: Tradition, Innovation and Pitfalls

According to WHO, "complementary feeding (CF) is the process starting when breast milk alone or infant formula alone is no longer sufficient to meet the nutritional requirements of infants, and therefore, other foods and liquids are needed, along with breast human milk or a breastmilk substitute". CF is one of the most important "critical and sensitive periods" in human life: indeed, timing and approaches to solid foods introduction in an infant's nutrition are of utmost importance as potential epigenetic factors from infancy to adulthood. CF is also deeply influenced by each country and single-family traditions, culture, and beliefs. The aim of our narrative review is to analyze traditional CF practices, including innovative and alternative ones that emerged in the last decades, such as baby-led weaning or plant-based weaning, and to evaluate their effects on the risk of developing non-communicable diseases. Moreover, we will discuss pitfalls and misunderstandings that pediatricians frequently have to face when dealing with complementary feeding. Health care professionals must not have prejudices against parents' wishes or traditions about CF; rather, they should support and educate them in case of any alternative CF choice, always pursuing the infant's adequate growth, neuro- and taste development, and the achievement of correct eating behavior as the primary goal.

Epidemiology and the Growing Epidemic of Food Allergy in Children and Adults Across the Globe

PURPOSE OF REVIEW

Food allergies are immune-mediated, complex disorders, which are the source of increasing health concern worldwide. The goal of this review is to present an updated summary of the food allergy (FA) burden among children and adults across different populations, focusing on research from the past 5 years.

RECENT FINDINGS

FAs impact a growing number of global residents-particularly those residing in higher-income, industrialized regions. Moreover, growing epidemiologic evidence suggests that the population health burden of non-IgE-mediated FAs, such as food protein-induced enterocolitis syndrome, may also be higher than previously reported. FA is a complex trait that impacts infants, children, as well as adults across the globe. The population health burden of both IgE- and non-IgE-mediated FAs is likely to grow in the absence of rapid advances and widespread implementation of effective FA prevention and treatment interventions. Systematic epidemiological research initiatives are needed, both nationally and globally, to better understand and reduce the burden of these allergic diseases.

Psychosocial Impact of Food Allergy on Children and Adults and Practical Interventions

PURPOSE OF REVIEW

IgE- and non-IgE-mediated food allergies are increasing in prevalence in children and adults worldwide. A food allergy diagnosis can be associated with a sense of overwhelm and stress and commonly has a negative impact on quality of life.

RECENT FINDINGS

While there is an increased recognition of the psychosocial effects of food allergy, the current research reflects the experience of mostly White, well-educated wealthier populations. Some studies have now explored the psychosocial impact among other populations; however, further study is needed. It is important that physicians and allied health professionals screen for the potentially negative psychosocial effects of food allergy and provide education to promote safety and self-efficacy at each visit; however, time may be a limiting factor. Numerous validated questionnaires are now available to help assess the psychosocial impact of food allergies. Allergy-friendly foods are typically more expensive, and thus, it is imperative that physicians screen for food insecurity as well. Educational resources should be offered regarding living well with food allergies at each visit. For patients and families experiencing anxiety or food allergy burden that is difficult to manage, referral to a mental health provider should be considered. Resources regarding programs to help accessing safe foods should also be available. Further research is needed among diverse populations focusing on interventions to best support patients and families with food allergy.

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.

Dietary Intervention during Weaning and Development of Food Allergy: What Is the State of the Art?

Food allergy (FA) affects approximately 6-8% of children worldwide causing a significant impact on the quality of life of children and their families. In past years, the possible role of weaning in the development of FA has been studied. According to recent studies, this is still controversial and influenced by several factors, such as the type of food, the age at food introduction and family history. In this narrative review, we aimed to collect the most recent evidence about weaning and its role in FA development, organizing the gathered data based on both the type of study and the food. As shown in most of the studies included in this review, early food introduction did not show a potential protective role against FA development, and we conclude that further evidence is needed from future clinical trials.

Management of Food Allergies and Food-Related Anaphylaxis

Importance

An estimated 7.6% of children and 10.8% of adults have IgE-mediated food-protein allergies in the US. IgE-mediated food allergies may cause anaphylaxis and death. A delayed, IgE-mediated allergic response to the food-carbohydrate galactose-α-1,3-galactose (alpha-gal) in mammalian meat affects an estimated 96 000 to 450 000 individuals in the US and is currently a leading cause of food-related anaphylaxis in adults.

Observations

In the US, 9 foods account for more than 90% of IgE-mediated food allergies-crustacean shellfish, dairy, peanut, tree nuts, fin fish, egg, wheat, soy, and sesame. Peanut is the leading food-related cause of fatal and near-fatal anaphylaxis in the US, followed by tree nuts and shellfish. The fatality rate from anaphylaxis due to food in the US is estimated to be 0.04 per million per year. Alpha-gal syndrome, which is associated with tick bites, is a rising cause of IgE-mediated food anaphylaxis. The seroprevalence of sensitization to alpha-gal ranges from 20% to 31% in the southeastern US. Self-injectable epinephrine is the first-line treatment for food-related anaphylaxis. The cornerstone of IgE-food allergy management is avoidance of the culprit food allergen. There are emerging immunotherapies to desensitize to one or more foods, with one current US Food and Drug Administration-approved oral immunotherapy product for treatment of peanut allergy.

Conclusions and Relevance

IgE-mediated food allergies, including delayed IgE-mediated allergic responses to red meat in alpha-gal syndrome, are common in the US, and may cause anaphylaxis and rarely, death. IgE-mediated anaphylaxis to food requires prompt treatment with epinephrine injection. Both food-protein allergy and alpha-gal syndrome management require avoiding allergenic foods, whereas alpha-gal syndrome also requires avoiding tick bites.

Reaching Communities Through Food Allergy Advocacy, Research, and Education: A Comprehensive Analysis

This article explores the multifaceted approach of food allergy (FA) advocacy, research, and education to address the diverse challenges associated with FA, such as disparities in socioeconomic status, food security, quality of life, and the overall burden of the disease. Advocacy initiatives are instrumental in driving policy changes, raising public awareness, and directing substantial research funding, with a focus on reducing disparities. They have influenced allergen labeling regulations and improved access to epinephrine, emphasizing the importance of school-based management plans, especially in underserved communities. Research in FA informs medical practices and offers them hope for improved treatments. Recent breakthroughs in peanut allergy prevention and oral immunotherapy trials exemplify the potential for advancements while highlighting the need to address disparities in health care access. Education is a critical tool for prevention, raising awareness, and reducing the risk of allergic reactions. Efforts should be tailored to reach marginalized communities, particularly in schools where education on FA management is essential. Collaborating directly with communities is imperative to ensure inclusivity and address disparities. Barriers such as mistrust, language and cultural differences, and lack of diversity among researchers must be overcome to encourage diverse participation in research studies. This article concludes by emphasizing the significance of a comprehensive approach to FA research that prioritizes equity and inclusivity. The call to action highlights the need for global initiatives to reshape the landscape of FA care and address disparities in health care access and outcomes.

Anaphylaxis: A 2023 practice parameter update

This practice parameter update focuses on 7 areas in which there are new evidence and new recommendations. Diagnostic criteria for anaphylaxis have been revised, and patterns of anaphylaxis are defined. Measurement of serum tryptase is important for diagnosis of anaphylaxis and to identify underlying mast cell disorders. In infants and toddlers, age-specific symptoms may differ from older children and adults, patient age is not correlated with reaction severity, and anaphylaxis is unlikely to be the initial reaction to an allergen on first exposure. Different community settings for anaphylaxis require specific measures for prevention and treatment of anaphylaxis. Optimal prescribing and use of epinephrine autoinjector devices require specific counseling and training of patients and caregivers, including when and how to administer the epinephrine autoinjector and whether and when to call 911. If epinephrine is used promptly, immediate activation of emergency medical services may not be required if the patient experiences a prompt, complete, and durable response. For most medical indications, the risk of stopping or changing beta-blocker or angiotensin-converting enzyme inhibitor medication may exceed the risk of more severe anaphylaxis if the medication is continued, especially in patients with insect sting anaphylaxis. Evaluation for mastocytosis, including a bone marrow biopsy, should be considered for adult patients with severe insect sting anaphylaxis or recurrent idiopathic anaphylaxis. After perioperative anaphylaxis, repeat anesthesia may proceed in the context of shared decision-making and based on the history and results of diagnostic evaluation with skin tests or in vitro tests when available, and supervised challenge when necessary.

Parental stress and food allergy phenotypes in young children: A National Birth Cohort (JECS)

BACKGROUND

Food allergy children and their families tend to have emotional distress and anxiety. There have been few reports of differences in parenting stress and a child's food allergy phenotypes.

METHODS

We examined the associations between food allergy phenotypes in children and parenting stress assessed by the Parenting Stress Index-Short Form (PSI-SF) from a national birth cohort (Japan Environment and Children's Study).

RESULTS

We included 65,805 children for statistical analysis. Of them, 7.2% of children had a food allergy diagnosis at 2 years old. The means of the total PSI-SF (39.9 ± 10.3, 39.1 ± 9.9), CD-SF (19.5 ± 5.4, 19.1 ± 5.2), and PD-SF (20.5 ± 6.3, 20.0 ± 6.1) scores are similar for caregivers in the with and without food allergy groups. Food allergy diagnosis resulted in significantly higher total PSI scores (coefficient .47, 95% CI 0.19-0.75, p = .001), CD-SF (coefficient .22, 95% CI 0.07-0.38, p = .004), and PD-SF (coefficient .24, 95% CI 0.08-0.41, p = .004). A similar trend was observed for allergy reactions to hen's egg. However, there was no clear relationship between allergic reactions to milk, wheat, nuts, and PSI-SF.

CONCLUSIONS

Parental stress was significantly related to a child's food allergy. Furthermore, hen's egg allergy increased parental stress. Multiple food avoidance might also increase parental stress. Healthcare providers need to be aware of parental stress in our daily clinic.

Complementary Feeding Practices: Recommendations of Pediatricians for Infants with and without Allergy Risk

AIM

To investigate the routine guidance provided by pediatricians concerning the timing of complementary feeding (CF) for both healthy infants and those at a heightened risk of allergies.

METHODS

A total of 233 pediatricians participated in an anonymous online survey that included questions about demographics and recommendations for CF. Specifically, they provided guidance on the types of foods, preparation methods, supplements, time intervals for introducing new foods to infants at low and high allergy risk, and delayed food introductions for high-risk cases.

RESULTS

The respondents advised introducing certain foods at specific ages: fruits, starchy non-gluten grains, vegetables, olive oil, and meat were appropriate at 6 months; gluten-rich grains at 7 months; yogurt, hard-boiled eggs, and legumes at 8 months; fish at 8.5 months; and nuts at 9 months. Pediatricians, especially those with less than 15 years of practice, often introduced egg, seafood, gluten-rich grains, legumes, and nuts earlier for high-risk infants. Parenthood and male gender were associated with the earlier introduction of eggs and grains.

CONCLUSIONS

Greek pediatricians follow a structured food introduction schedule for CF in infants. Interestingly, they tend to delay the introduction of common food allergens and recommend longer intervals between introducing new foods, particularly for high-risk infants. Key Notes: Despite recent evidence-based indications on healthy complementary feeding strategies for infants, discrepancies persist among pediatricians regarding food choices and the order and timing of food introduction, both for healthy infants and those at risk of allergy. Guidance on complementary feeding by pediatricians is influenced by their individual characteristics. Pediatricians tend to delay the introduction of common food allergens and recommend longer intervals between introducing new foods, particularly for high-risk infants.

Overviewing allergy epidemiology in Japan - Findings from birth cohorts (JECS and T-Child study)

The escalating global allergy epidemic has emerged as a pressing and persistent challenge, exerting a profound impact on human health systems across centuries. This burgeoning predicament can be attributed to contemporary lifestyles, environmental influences, and genetic predispositions. The manifestation of allergy-related factors exhibits dynamic fluctuations contingent on temporal shifts, geographical distinctions, cultural variances, and diverse demographic strata. In this review, we present recent epidemiological insights derived from two distinct birth cohorts: the Japan Environment and Children's Study (JECS), encompassing the entirety of Japan, and the Tokyo Children's Health, Illness, and Development Study (T-Child Study) within Tokyo. Through this comprehensive review, we offer a comprehensive overview of the latest epidemiological discoveries stemming from these pivotal Japanese birth cohorts, thereby affording a unique opportunity to deliberate on imperative strategies for the optimal management of the allergy epidemic.

Timing of complementary feeding for early childhood allergy prevention: An overview of systematic reviews

OBJECTIVE

To summarise and critically appraise systematic review (SR) evidence on the effects of timing of complementary feeding (CF) on the occurrence of allergic sensitisation and disease.

DESIGN

Overview of SRs. AMSTAR-2 and ROBIS were used to assess methodological quality and risk of bias (RoB) of SRs. RoB 2 Tool was used to assess RoB of primary randomised controlled trials (RCTs) (or extracted). The certainty of evidence (CoE) was assessed using GRADE. Findings were synthesised narratively.

DATA SOURCES

MEDLINE (via PubMed and Ovid), the Cochrane Library and Web of Science Core Collection (2010 to 27 February 2023).

ELIGIBILITY CRITERIA

SRs investigating the effects of timing of CF in infants or young children (0-3 years) on risk of developing food allergy (FA), allergic sensitisation, asthma, allergic rhinitis, atopic eczema and adverse events based on RCT evidence.

RESULTS

Eleven SRs were included. Only two SRs had low RoB; common issues were failure to report on funding of primary studies and failure to provide a list of excluded trials. Common limitations of included trials were lack of blinding of outcome assessment or detailed trial preregistration, and inadequate handling of high loss to follow up. Primary study overlap was very high for specific FA and slight to moderate for FA in general and other primary outcomes. Introducing specific foods (peanut, cooked egg) early probably reduces the risk of specific FA. Evidence for other allergic outcomes was mostly very uncertain and based on few primary studies. Trials varied regarding timing of CF, nature of complementary foods and population risk, which limited comparability between SRs.

CONCLUSIONS

For developing guidelines to support decision-making on the timing of CF as a preventive strategy, early introduction of specific foods (i.e. egg and peanut) seems promising and safe, whereas more extensive research is required regarding other allergic outcomes and potential adverse events.

Development of peanut, sesame and tree nut allergy in Polish children at high risk of food allergy: a protocol for a cross-sectional study

INTRODUCTION

Peanut allergies cause serious health problems worldwide. A strong finding has shown that the early introduction of peanuts into the diet of infants at high risk of food allergy reduces the prevalence of peanut allergy. Allergies to peanuts, sesame and tree nuts have been shown to coexist in 60% of cases and vary according to geographical location and dietary habits. Insights into the prevalence of nut and seed allergies in societies with varying consumption levels are essential for developing population-specific weaning guidelines. Understanding the age at which peanut allergy develops is paramount for successful early introduction strategies.

METHODS AND ANALYSIS

We will perform a cross-sectional study at two tertiary allergy centres in Warsaw and Bydgoszcz. Two hundred forty children aged 4-36 months with eczema or egg allergy will undergo an extensive assessment of their peanut, sesame and tree nut allergy status through skin testing, specific IgE measurements and oral food challenges. The primary outcome is the prevalence of peanut, sesame and tree nut allergies in Polish children at high risk of food allergy. Additionally, the timing of the development of peanut, sesame and tree nut allergies in the first 3 years of life in a high-risk population will be assessed.

ETHICS AND DISSEMINATION

The Ethics Committee of the Medical University of Warsaw, Poland approved this protocol (KB/86/2021). The results of this study will be submitted to a peer-reviewed journal no later than 1 year after data collection. The abstract will be presented at relevant national and international conferences.Although the authors may be able to commit to journal submission no later than 1 year after data collection, publication dates remain beyond their control.

TRIAL REGISTRATION NUMBER

NCT05662800.

Updates in Food Allergy Prevention in Children

Although significant evidence exists that feeding early has a role in the prevention of food allergy, this intervention in isolation may not be sufficient. Recent evidence highlights that early introduction of peanut specifically has had no significant impact on the populational prevalence of peanut allergy. Other factors that may contribute to food allergy prevention include regularity of ingestion once an allergen is introduced and consideration to the form in which the allergen is introduced (such as baked versus cooked egg). There are also many practicalities to early feeding and some discrepant viewpoints on these practicalities, which has led to poor implementation of early feeding strategies. In general, preemptive screening before food introduction is not recommended by most international allergy societies. Although there is little guidance to inform early introduction of allergens other than milk, egg, and peanut, the mechanism of sensitization is thought to be similar and there is no harm to early introduction. In terms of frequency and duration of feeding, there is little evidence to inform any concrete recommendations.

Oral immunotherapy as a curative treatment for food-allergic preschool children: Current evidence and potential underlying mechanisms

The worldwide rising prevalence of food allergy is a major public health concern. Standard care consists of allergen avoidance and rescue medication upon accidental exposure. Oral immunotherapy (OIT) is increasingly being studied as a treatment option. Although desensitization (an increased reaction threshold) is often achieved during OIT, sustained unresponsiveness (SU; clinical nonreactivity after finishing OIT) is not achieved in most patients. A few studies have investigated the effectiveness of OIT in children younger than 4 years of age (early = e-OIT) and have shown a much more favorable outcome in terms of SU development. Together with food allergy prevention studies, which have demonstrated high efficacy of early oral allergen exposure, the outcomes of e-OIT studies indicate an early-life window of opportunity to achieve SU, allowing unrestricted dietary intake. However, the underlying mechanism of the high effectiveness of e-OIT is not understood yet. Both cohort and OIT studies indicate early-life immune plasticity. An immature food-allergic response in the first years of life seems to be a major driver of this immune plasticity, along with a higher tolerogenic immunological state. Allergy maturation can likely be disrupted effectively by early intervention, preventing the development of persistent food allergy. Upcoming studies will provide important additional data on the safety, feasibility, and effectiveness of e-OIT. Combined with immune mechanistic studies, this should inform the implementation of e-OIT.

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

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

Association of umbilical cord serum TARC/CCL17 with childhood allergies: A birth cohort study

BACKGROUND

Early identification of infants at high risk of allergies can improve the efficacy of preventive interventions. However, an established quantifiable risk assessment method in the early postnatal period does not exist. TARC (or CCL17) is a Th2 chemokine used as an activity marker for atopic dermatitis (AD). Therefore, we evaluated the association between cord blood TARC (cTARC) and the development of allergic diseases in childhood.

METHODS

This is a high-risk birth cohort for allergy, consisting of children with a family history of allergy. We collected 263 pairs of maternal and child cord blood samples perinatally and child blood samples at ages 1, 2, and 5 years. TARC and allergen-specific immunoglobulin E levels were measured, and the relationship between allergic diseases was analyzed.

RESULTS

The median cTARC was 989 pg/mL (interquartile range [IQR]: 667-1430 pg/mL). The cTARC levels in children who developed AD were higher than those in children who did not develop AD, and the association strengthened with younger age (median [IQR] at 1 year: 1285 [816-1965] vs. 933 [662-1330] pg/mL, p < 0.01; at 2 years: 1114 [787-1753] vs. 950 [660-1373] pg/mL, p = 0.02). In the multivariate analysis, cTARC was associated with AD, egg white sensitization, food allergy, allergic rhinitis, and Japanese cedar pollen sensitization.

CONCLUSIONS

cTARC was associated with the development of allergic diseases and allergen sensitization in early childhood. These results suggest that, infantile AD-mediated atopic march starts during fetal life, and this immune status is reflected in the cTARC at birth.

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.

Food allergy and infant feeding practices: Are they related?

BACKGROUND

Immunoglobulin (Ig)E-mediated food allergy is a growing health problem affecting up to 10% of children. It is well-established that early introduction to peanuts and eggs from 4 months of age has a preventive effect. In contrast, there is no consensus about the effect of breastfeeding on food allergy development.

OBJECTIVE

To evaluate the effect of breastfeeding and cows' milk formula (CMF) feeding on the development of IgE-mediated food allergy.

METHODS

Infants in the Cow's Milk Early Exposure Trial were followed for 12 months. The cohort was divided according to parental feeding preferences for the first 2 months of life: group 1: exclusive breastfeeding (EBF); group 2: breastfeeding with at least 1 daily meal of CMF; and group 3: feeding with CMF only.

RESULTS

Among a total of 1989 infants, 1071 were on EBF (53.8%), 616 were breastfed with addition of CMF (31%), and 302 were fed with CMF only (15.2%), from birth. By 12 months, 43 infants developed an IgE-mediated food allergy (2.2%); 31 in the EBF group (2.9%), 12 in the breastfeeding and CMF combined group (1.9%), and none in the CMF feeding-only group (P = .002). Family atopic comorbidity did not affect the results.

CONCLUSION

In this prospective cohort, breastfed infants developed significantly higher rates of IgE-mediated food allergy during the first year of life. Perhaps the mechanism is related to compounds ingested by the mother and secreted in the breastmilk. Future larger cohorts should validate these results and offer the lactating mother recommendations.

TRIAL REGISTRATION

The COMEET study and its derivatives were approved by the Ethics Committee of Meir Medical Center, IRB number 011-16-MMC. It was registered at the National Institutes of Health Clinical Trials Registry: NCT02785679.

Complementary feeding practices are related to the risk of food allergy in the ELFE cohort

BACKGROUND

Conflicting results have been obtained when analyzing the relationship between complementary feeding (CF) practices and allergic diseases in childhood. This study aims to further explore the association between allergic diseases in early childhood (10.1016/j.jaci.2012.02.036) and the age at CF introduction (10.1016/S0140-6736(15)00149-X), food diversity in the first year of life (10.1016/j.ijporl.2019.109759) and the delayed introduction of major allergenic foods.

METHODS

This analysis focused on 6662 children from the French nationwide ELFE cohort. Data on feeding practices were collected monthly from 3 to 10 months old. Their age at CF introduction was calculated alongside a diversity score, and the number of major allergenic foods (out of eggs, fish, wheat, and dairy products) not introduced at 8 and 10 months. Their associations with parent-reported allergy-related health events between 1 and 5.5 years were assessed using logistic regressions adjusted for confounding factors. A sensitivity analysis excluding early allergic cases (occurring between 2 months and 1 or 2 years) was conducted.

RESULTS

Late CF (>6 months) was related to a higher risk of food allergy (OR [95% CI] = 1.35 [1.02; 1.78]), a low diversity score at 8 months to a higher risk of asthma (OR [95% CI] = 1.22 [1.01; 1.48]), and two allergenic foods or more not being introduced at 10 months to a higher risk of rhinoconjunctivitis (OR [95% CI] = 1.20 [1.00; 1.44]) and food allergy (OR [95% CI] = 2.46 [1.77; 3.42]). Only this last association remained significant after the exclusion of early cases.

CONCLUSION

The delayed introduction of major allergenic foods is related to a higher risk of food allergy, which supports the updated guidelines for allergy prevention.

Spanish Pediatricians' Positions Regarding Prevention, Diagnosis, Nutritional Management, and Challenges in Cow's Milk Protein Allergy

Management of cow's milk protein allergy (CMPA) can vary depending on the experience and area of expertise of the clinician responsible for the patient's follow-up, which may or may not align with the recently published literature. To analyze the perspectives of Spanish pediatricians on this topic, a survey was conducted. The survey aimed to determine the current opinions and attitudes of 222 primary care and hospital pediatricians toward CMPA prevention and nutritional management. Participating pediatricians completed the questionnaire, providing insights into their daily clinical practices, including access to testing, attitudes with respect to various aspects of CMPA diagnosis, prevention, oral food challenges, and treatment. The findings revealed that pediatricians generally agree on the use of extensively hydrolyzed formulas (eHFs) to prevent CMPA in high-risk atopic children, despite limited evidence supporting the widespread use of this practice. However, consensus was lacking regarding the utility of formulas with prebiotics and probiotics for expediting tolerance development. In most cases, pediatricians preferred eHFs for the nutritional management of CMPA, followed by hydrolyzed rice formulas (HRFs), with amino-acid-based formulas (AAFs) being the third option. Certain issues remained controversial among pediatricians, such as prevention methods, symptom assessment, and the role of probiotics. These variations in management approaches reflect the influence of clinician experience and area of expertise, underscoring the need for standardized guidelines in this field.

The SunBEAm birth cohort: Protocol design

Background

Food allergy (FA) and atopic dermatitis (AD) are common conditions that often present in the first year of life. Identification of underlying mechanisms and environmental determinants of FA and AD is essential to develop and implement effective prevention and treatment strategies. Objectives: We sought to describe the design of the Systems Biology of Early Atopy (SunBEAm) birth cohort.

Methods

Funded by the National Institute of Allergy and Infectious Diseases (NIAID) and administered through the Consortium for Food Allergy Research (CoFAR), SunBEAm is a US population-based, multicenter birth cohort that enrolls pregnant mothers, fathers, and their newborns and follows them to 3 years. Questionnaire and biosampling strategies were developed to apply a systems biology approach to identify environmental, immunologic, and multiomic determinants of AD, FA, and other allergic outcomes.

Results

Enrollment is currently underway. On the basis of an estimated FA prevalence of 6%, the enrollment goal is 2500 infants. AD is defined on the basis of questionnaire and assessment, and FA is defined by an algorithm combining history and testing. Although any FA will be recorded, we focus on the diagnosis of egg, milk, and peanut at 5 months, adding wheat, soy, cashew, hazelnut, walnut, codfish, shrimp, and sesame starting at 12 months. Sampling includes blood, hair, stool, dust, water, tape strips, skin swabs, nasal secretions, nasal swabs, saliva, urine, functional aspects of the skin, and maternal breast milk and vaginal swabs.

Conclusions

The SunBEAm birth cohort will provide a rich repository of data and specimens to interrogate mechanisms and determinants of early allergic outcomes, with an emphasis on FA, AD, and systems biology.

Infant egg consumption during introduction to solid food remains low in the United Kingdom but increases with infant age and a baby-led weaning approach

BACKGROUND

As a nutritious food-providing protein, essential fatty acids, vitamin D, iodine and choline eggs have historically been central to an infant weaning diet. However, food poisoning scares and allergy concerns have contributed to low consumption among infants aged 6-12 months.

METHODS

This paper presents a secondary data analysis of infant egg exposure and intake using three weaning data sets: a 7-day food frequency questionnaire (n = 297), a 24-h recall (n = 180) and a 3-day weighed food diary (n = 71). Egg introduction, frequency of consumption and intake in grams were analysed for infants aged 6-8, 9-10 and 11-12 months). Comparisons were made by whether infants were following a baby-led approach to weaning (where infants self-feed family foods) or a traditional approach where pureed foods are given alongside finger foods. Data were collected in the United Kingdom between 2015 and 2018.

RESULTS

Our data showed that despite introduction being recommended from the start of weaning at 6 months of age by the Department of Health, just 54% of infants aged 6-8 months had ever been offered eggs. Average egg intake was one to two times per week, increasing with age. However, in terms of frequency and grams consumed, our data suggest a small increase in consumption compared with previous research, although limitations of our smaller sample size should be noted. Finally, a baby-led approach was associated with increased exposure and consumption; baby-led infants consumed eggs twice as frequently as spoon-fed infants.

CONCLUSIONS

The findings have important implications for public health messaging and for supporting families in introducing solid foods.

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.

Primary Prevention of Allergy - Is It Feasible?

The allergy epidemic has been attributed to environmental influences related to urbanization and the modern lifestyle. In this regard, various theories exploring the role of microbes (hygiene, old friends, microbiota, and biodiversity hypotheses), and the epithelial barrier (epithelial, dual allergen exposure and vitamin D hypotheses) have been proposed. These hypotheses have guided clinical studies that led to the formulation of intervention strategies during the proposed window of opportunity dubbed as the "first thousand days." The most significant intervention is a paradigm shift from allergen avoidance to early introduction of allergenic foods, particularly egg and peanut, around 6 months of age for the prevention of food allergy. This recommendation has been adopted globally and included in allergy prevention guidelines. Other strategies with less robust clinical evidence include: encouraging a healthy balanced diet, rich in fish, during pregnancy; continuing allergenic food intake during pregnancy and lactation; vitamin D supplementation in pregnant women with asthma; discouraging social indications for caesarean section delivery; judicious use of antibiotics in early childhood; daily emollient use from birth in high risk babies; and avoiding cow's milk formula use in the first week of life. However, if early supplementation with cow's milk formula is required, continuing at least 10 mL of formula daily until age 2 months may be considered. Translating these strategies to public health and clinical practice is still a work in progress. Long-term population studies are crucial to assess the feasibility of these measures on allergy prevention.

Recent advances in cellular and molecular mechanisms of IgE-mediated food allergy

Food allergy is a public health issue the prevalence of which is steadily increasing. New discoveries have contributed to the understanding of the molecular and cellular mechanisms that lead to IgE-mediated food allergy. Novel scientific findings have defined roles for specific cell types, such as T follicular helper cells, in induction of high-affinity IgE by B cells. Also, not only mast cells and basophils contribute to food anaphylaxis, but also other cell types, such as neutrophils and macrophages. Elucidation of mechanisms involved in sensitization to food allergens through organs including the skin is key to deepening our understanding of the "dual exposure" hypothesis, which suggests that allergic sensitization is mainly acquired through inflamed skin while the oral route induces tolerance. This review considers the latest scientific knowledge about the molecular and cellular mechanisms of IgE-mediated food allergy. It reveals crucial components involved in the sensitization and elicitation phases and emerging approaches in anaphylaxis pathophysiology.

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.

Eggs: Healthy or Risky? A Review of Evidence from High Quality Studies on Hen's Eggs

Hen's eggs (from Gallus gallus domesticus) provide choline, folate, vitamin D, iodine, B vitamins and high-quality protein and are no longer viewed by national bodies as a risk factor for hypercholesterolaemia and cardiovascular disease (CVD). Yet, questions remain about the benefits and risks of eating eggs regularly. This review evaluates recent high-quality evidence from randomised controlled trials (RCT) and meta-analyses of observational studies and considers new areas of interest, such as weight management, protein metabolism, allergy risk and sustainability. In several RCT, eggs increased muscle protein synthesis and lowered fat mass, which could support optimal body composition. Eggs within a meal improved satiety, which could translate into lower energy intakes, although more RCT are needed. In observational studies, higher egg consumption was associated with a null effect or a modest reduced risk of CVD. For type 2 diabetes (T2D) incidence and risk of CVD in people with T2D, there were inconsistencies between observational and RCT data, with the former noting positive associations and the latter seeing no effect of higher egg intake on markers of T2D and CVD. Sustainability metrics suggest that eggs have the lowest planetary impact amongst animal proteins. To lower allergy risk, earlier introduction of eggs into weaning diets is warranted. In conclusion, the balance of evidence points to eggs being a nutritious food suggesting there are broad health benefits from including eggs in the diet at intakes higher than that currently consumed by European populations.

Oral allergy induction through skin exposure to previously tolerated food antigens in murine models

Food allergies (FAs) are caused by a failure of the immune system to regulate oral tolerance (OT). The use of soap containing hydrolyzed wheat overrides acquired OT to wheat through skin exposure. However, in mouse models, the experimental OT is robust, suggesting that acquired OT to allergens prevents the development of FAs. We aimed to analyze the mechanisms and developed a mouse model of FA that overrides acquired OT via skin exposure. Three murine FA models (intraperitoneal [IP], epicutaneous [EC], and intradermal [ID]) were compared to evaluate if allergies to ovalbumin (OVA) that had been previously tolerated orally could be induced. In the ID model, OT was overridden, and allergic reactions of severe anaphylaxis were developed. To analyze this effect in the ID model, we measured the migration of dendritic cells (DCs) into lymph nodes. The induction of OT promoted the migration of CD103⁺ dermal DCs; moreover, repeated percutaneous doses of OVA for sensitization gradually increased the migration of CD11b⁺ dermal DCs. The difference in the proportion of regulatory T cells between ID-sensitized groups at the first ID injection disappeared at the tenth injection. Although OT was robust in the IP model, ID sensitization was found to override OT.

Timing of Allergenic Food Introduction and Risk of Immunoglobulin E-Mediated Food Allergy: A Systematic Review and Meta-analysis

Importance

Earlier egg and peanut introduction probably reduces risk of egg and peanut allergy, respectively, but it is uncertain whether food allergy as a whole can be prevented using earlier allergenic food introduction.

Objective

To investigate associations between timing of allergenic food introduction to the infant diet and risk of food allergy.

Data Sources

In this systematic review and meta-analysis, Medline, Embase, and CENTRAL databases were searched for articles from database inception to December 29, 2022. Search terms included infant, randomized controlled trial, and terms for common allergenic foods and allergic outcomes.

Study Selection

Randomized clinical trials evaluating age at allergenic food introduction (milk, egg, fish, shellfish, tree nuts, wheat, peanuts, and soya) during infancy and immunoglobulin E (IgE)-mediated food allergy from 1 to 5 years of age were included. Screening was conducted independently by multiple authors.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was used. Data were extracted in duplicate and synthesized using a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation framework was used to assess certainty of evidence.

Main Outcomes and Measures

Primary outcomes were risk of IgE-mediated allergy to any food from 1 to 5 years of age and withdrawal from the intervention. Secondary outcomes included allergy to specific foods.

Results

Of 9283 titles screened, data were extracted from 23 eligible trials (56 articles, 13 794 randomized participants). There was moderate-certainty evidence from 4 trials (3295 participants) that introduction of multiple allergenic foods from 2 to 12 months of age (median age, 3-4 months) was associated with reduced risk of food allergy (risk ratio [RR], 0.49; 95% CI, 0.33-0.74; I2 = 49%). Absolute risk difference for a population with 5% incidence of food allergy was -26 cases (95% CI, -34 to -13 cases) per 1000 population. There was moderate-certainty evidence from 5 trials (4703 participants) that introduction of multiple allergenic foods from 2 to 12 months of age was associated with increased withdrawal from the intervention (RR, 2.29; 95% CI, 1.45-3.63; I2 = 89%). Absolute risk difference for a population with 20% withdrawal from the intervention was 258 cases (95% CI, 90-526 cases) per 1000 population. There was high-certainty evidence from 9 trials (4811 participants) that introduction of egg from 3 to 6 months of age was associated with reduced risk of egg allergy (RR, 0.60; 95% CI, 0.46-0.77; I2 = 0%) and high-certainty evidence from 4 trials (3796 participants) that introduction of peanut from 3 to 10 months of age was associated with reduced risk of peanut allergy (RR, 0.31; 95% CI, 0.19-0.51; I2 = 21%). Evidence for timing of introduction of cow's milk and risk of cow's milk allergy was very low certainty.

Conclusions and Relevance

In this systematic review and meta-analysis, earlier introduction of multiple allergenic foods in the first year of life was associated with lower risk of developing food allergy but a high rate of withdrawal from the intervention. Further work is needed to develop allergenic food interventions that are safe and acceptable for infants and their families.

[Early introduction of potentially allergenic foods in pediatric patients under six months of age]

OBJECTIVE

To review the available evidence on the early introduction of allergenic foods and the possible protection in the development of food allergy in later stages.

METHODS

An exploratory review of randomized clinical trials whose study population included infants less than 6 months of age at enrollment with or without a diagnosis of food allergy was conducted. For the purposes of this review, eggs, peanuts, and wheat were included as potentially allergenic foods. The following databases were consulted: Medline, EBSCO, OVID, Science Direct and JSTOR (Journal Storage), Scielo, LILACS, Redalyc and Imbiomed from August to December 2021.

RESULTS

429 articles were identified, 412 were excluded, and the final analysis included 9 studies that met the inclusion criteria. Six trials correspond to allergy to eggs, two to peanuts and one to wheat. The age of introduction differs in all trials. The earliest exposure was at 3.5 months and the latest at 5.5 months. The reduction in the risk of developing food allergy occurred in children at risk of allergy. Adverse reactions were common, particularly with the introduction of egg.

CONCLUSIONS

We found no evidence that early introduction (< 6 months of age) of allergenic foods reduces the risk of developing food allergy in infants without risk factors.

Quality of systematic reviews on timing of complementary feeding for early childhood allergy prevention

BACKGROUND

Only rigorously prepared analyses can provide the highest level of evidence to inform decision-making. Several recent systematic reviews (SRs) examined the hypothesis that the early introduction of specific allergenic complementary foods (CFs) to infants may lead to a lower incidence of one or more allergic outcomes. However, the methodological rigour and quality of reporting of SRs in this area has not yet been systematically evaluated.

METHODS

We comprehensively searched PubMed, Medline (Ovid), and Web of Science Core Collection on 13th January 2022, using a pre-specified and tested search syntax for SRs with RCT evidence on the early introduction of allergenic CFs as a means for allergy prevention in infants and children. We examined the quality and risk of bias (RoB) using AMSTAR-2 and ROBIS tools, examined adherence to the Preferred Reporting Items for SRs and Meta-Analyses (PRISMA), and checked whether certainty of the evidence was assessed.

RESULTS

Twelve SRs were included. Application of both tools resulted in similar overall judgements in terms of direction and extent for nine of the 12 SRs. Nine SRs were found to be of critically low to low quality according to AMSTAR-2 and to be at high RoB according to ROBIS. One SR received a moderate quality rating (AMSTAR-2) and high RoB rating (ROBIS). However, for two SRs, judgements between AMSTAR-2 and ROBIS were at stark variance. Only two SRs fully adhered to the PRISMA checklist. Six SRs evaluated the certainty of the body of RCT evidence. Several SRs failed to consider unpublished studies either by an explicit a priori exclusion or by inadequate search strategies.

CONCLUSIONS

Well-conducted SRs are important for decision-making and informing guideline development, the quality of their methodology should therefore be considered. The methodological rigour and the reporting quality of SRs on the timing of CF for allergy prevention must be improved.

REGISTRATION

https://osf.io/7cs4b .

A systematic review of quality and consistency of clinical practice guidelines on the primary prevention of food allergy and atopic dermatitis

Background and aims

With an increasing number of Clinical Practice Guidelines (CPGs) addressing primary prevention of food allergy and atopic dermatitis, it is timely to undertake a comprehensive assessment of the quality and consistency of recommendations and evaluation of their implementability in different geographical settings.

Methods

We systematically reviewed CPGs from 8 international databases and extensive website searches. Seven reviewers screened records in any language and then used the AGREE II and AGREE REX instruments to critically appraise CPGs published between January 2011 and April 2022.

Results

Our search identified 2138 relevant articles, of which 30 CPGs were eventually included. Eight (27%) CPGs were shortlisted based on our predefined quality criteria of achieving scores >70% in the "Scope and Purpose" and "Rigour of Development" domains of the AGREE II instrument. Among the shortlisted CPGs, scores on the "Applicability" domain were generally low, and only 3 CPGs rated highly in the "Implementability" domain of AGREE-REX, suggesting that the majority of CPGs fared poorly on global applicability. Recommendations on maternal diet and complementary feeding in infants were mostly consistent, but recommendations on use of hydrolysed formula and supplements varied considerably.

Conclusion

The overall quality of a CPG for Food Allergy and Atopic Dermatitis prevention did not correlate well with its global applicability. It is imperative that CPG developers consider stakeholders' preferences, local applicability, and adapt existing recommendations to each individual population and healthcare system to ensure successful implementation. There is a need for development of high-quality CPGs for allergy prevention outside of North America and Europe.

PROSPERO registration number

CRD42021265689.

Pathogenesis of allergic diseases and implications for therapeutic interventions

Allergic diseases such as allergic rhinitis (AR), allergic asthma (AAS), atopic dermatitis (AD), food allergy (FA), and eczema are systemic diseases caused by an impaired immune system. Accompanied by high recurrence rates, the steadily rising incidence rates of these diseases are attracting increasing attention. The pathogenesis of allergic diseases is complex and involves many factors, including maternal-fetal environment, living environment, genetics, epigenetics, and the body's immune status. The pathogenesis of allergic diseases exhibits a marked heterogeneity, with phenotype and endotype defining visible features and associated molecular mechanisms, respectively. With the rapid development of immunology, molecular biology, and biotechnology, many new biological drugs have been designed for the treatment of allergic diseases, including anti-immunoglobulin E (IgE), anti-interleukin (IL)-5, and anti-thymic stromal lymphopoietin (TSLP)/IL-4, to control symptoms. For doctors and scientists, it is becoming more and more important to understand the influencing factors, pathogenesis, and treatment progress of allergic diseases. This review aimed to assess the epidemiology, pathogenesis, and therapeutic interventions of allergic diseases, including AR, AAS, AD, and FA. We hope to help doctors and scientists understand allergic diseases systematically.

Introduction of Egg White and Yolk to Infant Diets and Early Childhood Atopic Dermatitis

This study investigated whether the introduction of allergenic foods in infancy is associated with atopic dermatitis (AD) in early childhood. Information regarding parental allergic histories, the introduction of six possible allergenic foods (fruits, egg white, egg yolk, fish, shellfish, and peanuts), and physician-diagnosed AD was obtained using age-specific questionnaires (0–2 years). Immunoglobulin E, specific to 20 food allergens, was also quantified at 12 months of age. Logistic regression analyses were used to determine the association between individual food introduction and the outcomes of food sensitization and AD. We found AD development by 2 years of age was significantly related to a parental history of allergy (adjusted odds ratio (aOR) = 1.29) and not being introduced to egg white and yolk during infancy (aORs = 2.27 and 1.97, respectively). Stratified analyses revealed that the introduction of both egg white and yolk was negatively associated with AD by 2 years of age, especially for those children where both parents had allergic diseases (aOR = 0.10). In summary, the introduction of egg white and yolk to an infant’s diet may be a modifiable factor in reducing the risk of physician-diagnosed AD by 2 years of age, which may be particularly important for infants where both parents have allergies.

Prevention of food allergy in infancy: the role of maternal interventions and exposures during pregnancy and lactation

There is increased focus on the role of maternal interventions in the prevention of food allergy in infancy. There is no role for maternal dietary modifications during pregnancy or lactation, such as allergen avoidance, as a means of infant allergy prevention. Although exclusive breastfeeding is the recommended infant nutrition source globally, the effect of breastfeeding on infant allergy prevention remains unclear. There is emerging evidence that irregular cow's milk exposure (ie, infrequent formula supplementation) might increase the risk of cow's milk allergy. Although further studies are required, there is also emerging evidence that maternal peanut ingestion during breastfeeding along with early peanut introduction in infancy might have a preventive role. The effect of maternal dietary supplementation with vitamin D, omega-3, and prebiotics or probiotics remains unclear.

Epicutaneous Sensitization and Food Allergy: Preventive Strategies Targeting Skin Barrier Repair-Facts and Challenges

Food allergy represents a growing public health and socio-economic problem with an increasing prevalence over the last two decades. Despite its substantial impact on the quality of life, current treatment options for food allergy are limited to strict allergen avoidance and emergency management, creating an urgent need for effective preventive strategies. Advances in the understanding of the food allergy pathogenesis allow to develop more precise approaches targeting specific pathophysiological pathways. Recently, the skin has become an important target for food allergy prevention strategies, as it has been hypothesized that allergen exposure through the impaired skin barrier might induce an immune response resulting in subsequent development of food allergy. This review aims to discuss current evidence supporting this complex interplay between the skin barrier dysfunction and food allergy by highlighting the crucial role of epicutaneous sensitization in the causality pathway leading to food allergen sensitization and progression to clinical food allergy. We also summarize recently studied prophylactic and therapeutic interventions targeting the skin barrier repair as an emerging food allergy prevention strategy and discuss current evidence controversies and future challenges. Further studies are needed before these promising strategies can be routinely implemented as prevention advice for the general population.

A Murine Model of Food Allergy by Epicutaneous Adjuvant-Free Allergen Sensitization Followed by Oral Allergen Challenge Combined with Aspirin for Enhanced Detection of Hypersensitivity Manifestations and Immunotherapy Monitoring

Food allergy is one of the major existing health problems, but no effective treatment is available. In the current work, a murine model that closely mimics pathogenesis of human food allergy and its quantifiable diagnostic parameter design, even for mild hypersensitivity reactions, were established. BALB/c mice were epicutaneously sensitized with 1 mg chicken egg ovomucoid (OVM) or cow's milk casein, free of adjuvants, five times a week for two consecutive weeks. Eleven days later, allergen-specific IgG1 and IgE in serum were measured by ELISA. On day 25, 20 mg OVM or 12 mg α-casein was administered orally, and allergic reactions such as the fall in rectal temperature, symptom scores during 90-120 min, serum mast cell protease-1 and cytokine levels were monitored. The detection of mild allergic reactions due to adjuvant-free allergen sensitization and oral allergen challenge routes was amplified by the combination of oral allergen and aspirin administration simultaneously or aspirin administration within 15-30 min before an allergen challenge. Quantification of the maximum symptom score and the frequency of symptoms during the monitoring period improved evaluation accuracy of food allergy signals. Based on these results, efficacy of casein oral immunotherapy for cow's milk allergies, which are generally difficult to detect, was monitored adequately.

Oral Immunotherapy

Oral immunotherapy (OIT) is an alternative treatment of IgE-mediated food allergy that has been shown to increase tolerance threshold to many of the top food allergens, although this effect may be dependent on age, dose, frequency, and duration. OIT has been shown to be effective and safe in infants, and early initiation can improve rates of desensitization even for those foods whose natural history favors loss of allergy. Studies looking at protocol modification to improve OIT success are ongoing as is the evaluation of clinical tools to help monitor OIT effects.

Early, continuing exposure to cow's milk formula and cow's milk allergy: The COMEET study, a single center, prospective interventional study

BACKGROUND

Cow's milk allergy (CMA) is a common food allergy among infants. Information regarding the best timing for first exposure to cow's milk formula (CMF) is controversial and more evidence is required. Few randomized control trials have tried to accurately assess the timing and preventive effect of exposure to CMF on small cohorts.

OBJECTIVE

This study assessed the association between early, continuing exposure to CMF on the basis of the parents' preferences and the development of immunoglobulin E (IgE)-mediated CMA in a large birth cohort.

METHODS

Newborns were prospectively recruited shortly before birth and divided into 2 groups according to parental feeding preference for the first 2 months of life: (1) exclusive breastfeeding (EBF); or (2) at least 1 meal of CMF (with or without breastfeeding) daily. Infants were followed up monthly until the age of 12 months.

RESULTS

Among 1992 infants participating in the study, 1073 (53.86%) were in the EBF group until 2 months of age. IgE-mediated CMA was confirmed in 0.85% (n = 17); all were in the EBF group. Within this group, the prevalence of IgE-mediated CMA was 1.58% compared with 0 in the other groups (relative risk, 29.98; P < .001). Post hoc analysis revealed IgE-mediated CMA prevalence of 0.7% in the per-protocol EBF group vs 3.27% among breastfed infants who were exposed to a small amount of CMF during the first 2 months of life. A family atopic background did not affect the results.

CONCLUSION

Early, continuing exposure to CMF from birth has the potential to prevent the development of IgE-mediated CMA and should be encouraged. However, the exposure needs to be consistent because occasional exposure increases the risk of developing IgE-mediated CMA and should be avoided.

The clinical and immunological basis of early food introduction in food allergy prevention

IgE-mediated food allergy has an estimated prevalence of 6%-10% in developed countries. Allergen avoidance has long been the main focus in the prevention of food allergy and late solid food introduction after 6-12 months of age was recommended in high-risk infants. However, the rising prevalence of food allergy despite delayed exposure to allergens and the observations that IgE-mediated sensitization to food products could even occur before the introduction of solid foods resulted in a shift towards early solid food introduction as an attempt to prevent IgE-mediated food allergy. Since then, many trials focused on the clinical outcome of early allergen introduction and overall seem to point to a protective effect on the development of IgE-mediated food allergies. For non-IgE-mediated diseases of food allergy, evidence of early food introduction seems less clear. Moreover, data on the underlying immunological processes in early food introduction is lacking. The goal of this review is to summarize the available data of immunological changes in early food introduction to prevent IgE and non-IgE mediated food allergy.