Prevention of food allergy - Early dietary interventions

Worldwide Heterogeneity of Food Allergy: Focus on Peach Allergy in Southern Italy

Food allergy (FA) has shown an increasing prevalence in the last decades, becoming a major public health problem. However, data on the prevalence of FA across the world are heterogeneous because they are influenced by several factors. Among IgE-mediated FA, an important role is played by FA related to plant-derived food which can result from the sensitization to a single protein (specific FA) or to homologous proteins present in different foods (cross-reactive FA) including non-specific lipid transfer proteins (nsLTPs), profilins, and pathogenesis-related class 10 (PR-10). In addition, the clinical presentation of FA is widely heterogeneous ranging from mild symptoms to severe reactions up to anaphylaxis, most frequently associated with nsLTP-related FA (LTP syndrome). Considering the potential life-threatening nature of nsLTP-related FA, the patient's geographical setting should always be taken into account; thereby, it is highly recommended to build a personalized approach for managing FA across the world in the precision medicine era. For this reason, in this review, we aim to provide an overview of the prevalence of nsLTP-mediated allergies in the Mediterranean area and to point out the potential reasons for the different geographical significance of LTP-driven allergies with a particular focus on the allergenic properties of food allergens and their cross reactivity.

The Role of Diet and Nutritional Interventions for the Infant Gut Microbiome

The infant gut microbiome plays a key role in the healthy development of the human organism and appears to be influenced by dietary practices through multiple pathways. First, maternal diet during pregnancy and infant nutrition significantly influence the infant gut microbiota. Moreover, breastfeeding fosters the proliferation of beneficial bacteria, while formula feeding increases microbial diversity. The timing of introducing solid foods also influences gut microbiota composition. In preterm infants the gut microbiota development is influenced by multiple factors, including the time since birth and the intake of breast milk, and interventions such as probiotics and prebiotics supplementation show promising results in reducing morbidity and mortality in this population. These findings underscore the need for future research to understand the long-term health impacts of these interventions and for further strategies to enrich the gut microbiome of formula-fed and preterm infants.

Trends in the prevalence of breastfeeding up to 6 months of age using structured data from routine child healthcare visits

AIM

The Norwegian Action Plan for a Healthier Diet (2017-2021) set the target that 25% of infants should be exclusively breastfed for 6 months by 2022. Our aim was to determine trends in the prevalence and duration of breastfeeding in the municipality of Bergen.

METHODS

Data on breastfeeding status in 2010-2018 were extracted from a standardised electronic medical record kept by public child health centres and recorded as exclusive, partial or none, at 6 weeks and 6 months of age.

RESULTS

We found that 28,503 and 26,735 infants attended the 6-week and 6-month consultations, respectively. The prevalence of any breastfeeding was 92.0% at 6 weeks and 78.0% at 6 months with no trend over time between 2010 and 2018. The prevalence of exclusive breastfeeding at 6 weeks was 73.9% and stable over time, but it declined at 6 months, from 28.1% in 2010 to 11.1% in 2014 and remained stable thereafter.

CONCLUSION

During 2010-2018, the prevalence of any and exclusive breastfeeding at 6 weeks and any breastfeeding at 6 months was stable. Exclusive breastfeeding at 6 months declined halfway through the study period, to a stable, but low, prevalence of 11.1% by 2014.

Oral Tolerance Induction-Opportunities and Mechanisms

Oral tolerance is the active absence of response to food allergens, which involves complex mechanisms in the gut-associated lymphoid tissue. Food allergy results from the disruption of such tolerance or the absence of its establishment in the first place. It follows allergic sensitization with the production of allergen-specific IgE and results from the degranulation of basophils and mast cells on subsequent exposure to the allergen. Oral tolerance induction has been explored in the contexts of prevention and treatment of food allergy. Early introduction of allergenic foods (i.e., egg and peanut) in the diet of infants, before allergic sensitization occurs (i.e., via inflamed skin affected with eczema) has shown to be beneficial. Guidelines have changed to recommend the introduction of these allergenic foods by 6 months of age. For food allergic individuals, oral tolerance induction has been attempted using allergen-specific immunotherapy, which involves the administration of an allergen, modified or not, through various possible routes, including oral, sublingual, epicutaneous, and subcutaneous, with or without concomitant administration of antibody-based biologics. Further research into the immune mechanisms of food allergy and oral tolerance can lead to the identification of novel targets to suppress the food allergic response and reverse the current food allergy epidemic.

Factors associated with parental burden among parents of children with food allergies in China: a cross-sectional study

OBJECTIVE

This study aimed to investigate the factors associated with parental burden among parents of children with food allergies (FA) in China.

DESIGN

Cross-sectional study.

SETTING

The participants were recruited through the internet and one child health centre of a tertiary hospital in Changsha, China.

PARTICIPANTS

A total of 346 parents of children with FA were recruited using a convenience sampling method. After excluding the invalid questionnaires, 330 questionnaires were included for the analysis.

OUTCOME MEASURES

The data of general and disease-specific information of children with FA and their parents, as well as parental burden, social support and coping style of parents, were collected using a self-developed questionnaire and standard measurement tools with good psychometric properties. Univariate analysis and multivariate stepwise regression analysis were used to analyse the data.

RESULTS

Financial affordability regarding their children's FA and parents' social support were key protective factors against parental burden (β=-0.224, p<0.001 and β=-0.226, p<0.001, respectively). This study also found that parents' working conditions, the number of highly suspected food allergens, the number of children's FA-affected systems and whether children took amino acid milk powder were the factors associated with parental burden.

CONCLUSIONS

Health professionals should pay more attention to parents who are not at work and whose children have more highly suspected food allergens and more FA-affected systems because these parents often have a higher parental burden. Furthermore, it is important to improve financial support for children's FA and social support for parents of children with FA to decrease their parental burden.

Advances in the Relationships Between Cow's Milk Protein Allergy and Gut Microbiota in Infants

Cow's milk protein allergy (CMPA) is an immune response to cow's milk proteins, which is one of the most common food allergies in infants and young children. It is estimated that 2-3% of infants and young children have CMPA. The diet, gut microbiota, and their interactions are believed to be involved in the alterations of mucosal immune tolerance, which might lead to the development of CMPA and other food allergies. In this review, the potential molecular mechanisms of CMPA, including omics technologies used for analyzing microbiota, impacts of early microbial exposures on CMPA development, and microbiota-host interactions, are summarized. The probiotics, prebiotics, synbiotics, fecal microbiota transplantation, and other modulation strategies for gut microbiota and the potential application of microbiota-based design of diets for the CMPA treatment are also discussed. This review not only summarizes the current studies about the interactions of CMPA with gut microbiota but also gives insights into the possible CMPA treatment strategies by modulating gut microbiota, which might help in improving the life quality of CMPA patients in the future.

Oral Immunotherapy in Patients with IgE Mediated Reactions to Egg White: A Clinical Trial Study

BACKGROUND

Oral immunotherapy (OIT) is under consideration as a promising treatment for desensitization of egg-allergic patients. The objective of this study was to assess the effectiveness of egg-white OIT in patients with IgE-mediated allergy to egg white and to compare the clinical and laboratory findings before and after OIT.

METHODS

This clinical trial was performed from February to August 2018 in Rasool e Akram Hospital, Tehran, Iran. Patients' selection criteria included a history of allergic symptoms, skin prick test (SPT) reactivity to egg white, and the inability to pass the Oral Food Challenge (OFC). Egg-white OIT was done for eight patients in the OIT group for 6 months while egg-white-free products were administrated for controls. The SPT reactivity, specific IgE, and IgG4 for egg white and ovomucoid were evaluated before and after OIT.

RESULTS

Hundred percent of the subjects in OIT group were desensitized and tolerated 40 cc raw egg white following 6-month maintenance whereas none of the controls was able to pass the OFC. The findings obtained from the evaluations indicated a significant decrease in the wheal size and specific IgE to egg white after OIT (P = .001). Furthermore, a significant decrease of IgE/IgG4 ratio to egg white was found in OIT group (P = .01).

CONCLUSION

This OIT protocol was successful as all OIT patients were able to continue 6-month OIT process and the reaction threshold to egg white increased in the OIT group. Therefore, it could be regarded as an effective and safe protocol to treat egg-allergic patients.

The evidence for interventions in early childhood allergy prevention - towards a living systematic review: protocol

Background: Research in early childhood allergy prevention (ECAP) is flourishing and new intervention strategies have proven to be promising. Due to the dynamic nature of ECAP, gaps between what is known and how guidelines inform practice are likely. A living systematic review (LSR) can narrow this gap by incorporating new evidence as it becomes available. No efficacy comparisons across various ECAP interventions for similar outcomes have been carried out. Networks of randomised clinical trials can be evaluated in the context of a network meta-analysis (NMA). We aim to establish a LSR on the efficacy and safety of any intervention investigated in randomised controlled trials (RCT) to prevent the occurrence of allergic sensitisation (AS), symptoms or diagnoses of allergic diseases in infancy and early childhood (0-3 years). Methods: A baseline SR will synthesise the evidence from existing SRs of RCTs as well as RCTs not yet considered in these. After completion of the baseline SR we propose to conduct a LSR. Using this methodology, we aim to undertake constant evidence surveillance, three-monthly search updates, and review updates every three months, should new evidence emerge. Conclusions: The ECAP evidence landscape has undergone dramatic transformations and this process is likely to continue. As a response to this, a LSR offers the potential to allow more timely synthesis of new evidence as it emerges. Long gaps between updates of SRs makes it harder for guidelines and recommendations to be up to date. Users of information, such as parents, may be confused if they encounter new evidence that is not part of a trusted guideline. A LSR approach allows us to continuously search the literature and update the evidence-base of existing ECAP interventions resulting in a decreased timespan from evidence accrual to informing clinical practice.

Advancing Food Allergy Through Epidemiology: Understanding and Addressing Disparities in Food Allergy Management and Outcomes

Epidemiological studies have been pivotal in advancing understanding of the etiology of food allergy and in guiding the development of evidence-based guidelines for food allergy prevention and clinical management. In recent years, as research into the population-level distribution and determinants of food allergy has accumulated, data indicate that substantial differences in food allergy outcomes and management exist across racial/ethnic and other socioeconomic strata. This clinical commentary aims to provide a review of existing epidemiological studies and shed valuable light on the disparate burden of food allergy. Emerging methods to quantify environmental exposure and food allergy outcomes are detailed, as are specific areas in which future research is warranted. We also highlight the role that epidemiology plays in advancing health equity and provide a framework as to how it can effectively inform health policy at all phases of the policy cycle-from initial population health assessment to the evaluation and refinement of specific health policies (ie, national guidelines to promote earlier introduction of peanut-containing foods for allergy prevention).

Adolescents Living with Food Allergies in Select Global Cities: Does a WhatsApp-Based Mindful Eating Intervention Promote Wellbeing and Enhance their Self-Concept?

PURPOSE

Food allergy prevalence in children and adolescents is increasing globally. Dietary restrictions are linked to the identities of food-allergic adolescents, which influences their wellbeing and self-concept. Mindful eating (ME) has been widely used to treat eating disorders. This study investigates whether WhatsApp-based mindful eating (ME) posts are effective for food-allergic adolescents in managing the condition, building self-concept and wellbeing.

DESIGN AND METHODS

A waitlist control design study was conducted with food-allergic adolescents (N _pre-test = 244; N _post-test = 215). Three measures were used to assess the outcomes pre- (T1) and post-test (T2): Mindful Eating Questionnaire (MEQ), Brief Psychological Wellbeing Scale for Adolescents (BPWBS-A), and Piers-Harris 2 Children's Self-Concept Scale (PH-2-CSCC).

RESULTS

The intervention was overall effective and more so for girls, middle class adolescents, with mothers as primary caregivers, whose primary caregivers had higher or postgraduate and professional qualifications, who were in turn also more likely to report no anaphylactic reaction and hospitalization emergency episodes at T2. Intervention compliance mediated the association between demographic predictors and outcome scores. Discriminant function analysis indicated stronger associations between certain predictors and subdomains of the self-concept outcome.

CONCLUSIONS

With adequate emphasis on intervention compliance and condition management, the WhatsApp-based ME posts would be effective for food-allergic adolescents.

PRACTICAL IMPLICATIONS

Pediatric nurses can recommend the intervention for community-dwelling food-allergic adolescents across contexts. Some refinements may be needed for boys, upper class adolescents, with father/kin as primary caregivers and less qualified parents.

An epidemiological investigation of food allergy among children aged 3 to 6 in an urban area of Wenzhou, China

BACKGROUND

The prevalence of food allergy (FA) has increased worldwide. In China, the prevalence of FA in infants and school-aged children is well known, but the prevalence in preschool children is unknown.

METHODS

A total of 4151 preschool children aged 3 to 6 years in urban Wenzhou, China, were recruited for this cross-sectional study. Their parents completed a preliminary screening questionnaire, and a detailed FA questionnaire was given to parents whose children had suspected FA according to the preliminary screening. According to the results of the detailed FA questionnaires, some children underwent a skin prick test (SPT) and specific IgE (sIgE) measurement. Children with abnormal SPT and/or sIgE results who did not meet the diagnostic criteria and those with negative SPT and sIgE results whose histories strongly supported FA underwent an oral food challenge (OFC).

RESULTS

Of the 4151 children's parents who completed the surveys, 534 (12.86%) indicated a positive medical history of FA. Among the 40 children who underwent an OFC, 24 were positive. According to SPT and sIgE measurements, 11 children were diagnosed with FA. The prevalence of FA was at least 0.84%; children who dropped out during the study were considered FA-negative. Among the 35 children with FA, the most common allergic manifestation was skin symptoms. The most common allergic foods were egg, fish and shrimp.

CONCLUSIONS

The parent-reported rate of FA in preschool children in urban Wenzhou was 12.86%. The prevalence of FA was at least 0.84%. Among all cases, the most common allergic food was eggs, and the most common allergic manifestation was skin symptoms.

TRIAL REGISTRATION

NCT03974555, registered on 30 May 2019 (www.clinicaltrials.gov).

Food Hypersensitivity Reactions to Seafish in Atopic Dermatitis Patients Older than 14 Year of Age - The Evaluation of Association with Other Allergic Diseases and Parameters

Background

Seafood allergy is among one of the common food allergies. Decrease in consumption of omega-3 polyunsaturated fatty acids (PUFAs), prevalent especially in oily fish, has been proposed to contribute to the increased prevalence of allergic diseases.

Aim

The aim of this study was to evaluate, in atopic dermatitis (AD) patients, the relation between the occurrence of food hypersensitivity reaction (FHR) to seafish and the occurrence of other atopic diseases and parameters.

Methods

Complete dermatological and allergological examination was performed in patients included in the study; 332 patients were examined, with the average age 26.8 years (SD 9.2 years).

Results

The FHR to seafish was confirmed in 11% of patients. Patients suffering from FHR to seafish suffered significantly more from sensitization to fungi (in 46%), from reactions to celery (in 34%), and from persistent eczematic lesions (in 82%).

Conclusion

FHRs to seafish in AD patients are associated with persistent eczematic lesions and with the higher occurrence of sensitization to fungi and reactions to celery. The occurrence of bronchial asthma, rhinitis, positive family history, and onset of AD under 5 years of age is higher in patients with reactions to seafish, but the difference is not statistically significant.

Nutrition and Avoidance Diets in Children With Food Allergy

Food allergy (FA) is a significant health issue which considerably influences the quality of life of both children and their family. The increasing prevalence of FA, documented in the last 3 decades, has led to the reassessment of FA prevention strategies and particularly to giving up the approach based on delaying the introduction of potential food allergens. Several observational and interventional studies demonstrated a potential effectiveness of the early food introduction strategy in FA prevention, although strong evidence from randomized controlled trials are lacking and, sometimes, contrasting. The current approach to FA is mainly based on avoidance diet and the use of rescue medications in case of allergic reaction, although active allergen immunotherapy has recently become an increasingly important therapeutic strategy to approach IgE-mediated FA, potentially able to induce improvement through desensitization to a specific food. This review provides an overview on the historical evolution of recommendations about FA and on evidence published in the last 15 years on nutritional intervention strategy, i.e., early introduction of allergen or avoidance diet, in the prevention and management of IgE-mediated and non-IgE-mediated FA in children.

Influences of Maternal Factors Over Offspring Allergies and the Application for Food Allergy

The prevalence of food allergy has been steadily rising worldwide with the highest incidence noted among younger children, and increasingly recognized as a growing public concern. The first known ingestion of foods often causes allergic reaction, suggesting that sensitization of offspring with food allergens may occur during pregnancy and/or through breastfeeding. This creates a milieu that shapes the neonatal immune responses to these allergens. However, the effects of maternal allergen exposure and maternal sensitization with allergens on development of allergies in offspring remain controversial. This review discusses recent advances from human data in our understanding of how maternal factors, namely, food allergens, allergen-specific immunoglobulins, cytokines, genetics, and environmental factors transferred during pregnancy or breastfeeding influence offspring allergies and how such effects may be applicable to food allergy. Based on information obtained from mouse models of asthma and food allergy, the review also dissects the mechanisms by which maternal factors, including the impact of immune complexes, transforming growth factor-β, vitamin A, and regulatory T-cell responses, contribute to the induction of neonatal tolerance vs. development of allergic responses to maternally transferred allergens.

How to prevent food allergy during infancy: what has changed since 2013?

PURPOSE OF REVIEW

The purpose of this review is to summarize recent studies and emerging consensus guidelines regarding food allergy prevention in infants of the past 5 years.

RECENT FINDINGS

Prior to 2013, the general consensus regarding prevention of food allergy in infants was to recommend delayed introduction or complete avoidance of commonly allergenic foods, such as milk, egg and peanut. However, in the past 5 years, several landmark studies have been conducted, particularly with peanut. The results of these studies have led to a paradigm shift from recommending delayed introduction to early introduction and frequent feeding of highly allergenic foods such as peanut, with hopes of achieving primary and secondary prevention of food allergy in infants.

SUMMARY

Recent clinical trials have demonstrated that early introduction and frequent feeding, rather than delayed introduction or complete avoidance, of commonly allergenic foods plays a critical role in preventing food allergy in infants. More studies are required to risk-stratify infants by personal and family atopic history to tailor guidelines for groups with inherently different risks. The universal acceptance of the guidelines and their application outcome are still to be determined.

Parental concerns of allergy or hypersensitivity and the infant's diet

AIM

To investigate a possible association between children's current diet and parents' reported avoidance of appropriate foods in the child's diet at the age of 10 months, due to fears of allergic or hypersensitivity reactions.

DESIGN

A cross-sectional study.

METHODS

In 10 randomly selected municipalities willing to participate, 686 children represented by their parents visiting the child health centre were enrolled in the study. From January 2015-January 2017, 440 (64%) parents completed a semi-quantitative food frequency questionnaire concerning their child.

RESULTS

Thirty-four percent of parents reported that they avoided introducing some food items due to fears of allergy or hypersensitivity in their child. A statistically significant relationship emerged between this reporting and parents wanting more information about food for infants and toddlers. However, the reported fear was not associated with dietary restrictions regarding actual feeding of the child.

Allergy to Peanuts in Atopic Dermatitis Patients 14 Year or Older and the Association with Food Hypersensitivity, Inhalant Allergens, Asthma Bronchiale and Rhinitis

BACKGROUND

In adult patients suffering from atopic dermatitis (AD), studies investigating the co-prevalence of AD and food allergy are still scarce, and exact data are not available.

AIMS AND OBJECTIVES

To evaluate the occurrence of food allergy to peanuts in significant relation to food hypersensitivity, inhalant allergy and to asthma bronchial and rhinitis.

MATERIALS AND METHODS

Altogether 332 patients of AD 14 year or older were included in the study. The complete dermatological and allergological examinations were performed in all included patients (including examination of specific immunoglobulin E, skin prick test to different food and inhalant allergens, anamnestic data about food reactions, evaluation of allergic rhinitis, and allergic asthma bronchiale). We evaluated whether there was some relation between the food allergy to peanuts and followed parameters. Pairs of these categories were entered in the contingency tables, and the Chi-square test for the relationship of these variables was performed with the level of significance set to 5%.

RESULTS

Altogether 332 persons suffering from AD were included in the study of which 120 were male and 212 were female; the average age was 27.2 year. The significant relation between the allergy to peanuts and the occurrence of food hypersensitivity (FH) reactions to tomatoes, kiwi, apples, oranges, carrot and to the sensitization to grass, trees, mites, and the occurrence of rhinitis was found.

CONCLUSION

The significant relation between the allergy to peanuts and the occurrence of FH reactions and the sensitization to inhalant allergens and rhinitis was found. The future studies may show if the decrease in food allergy to peanuts can lead to the decrease of the occurrence of other FH reactions and sensitization to inhalant allergens and rhinitis in AD patients.

Development of the gut microbiota in infancy and its impact on health in later life

Gut microbial ecology and function are dynamic in infancy, but are stabilized in childhood. The 'new friends' have a great impact on the development of the digestive tract and host immune system. In the first year of life, especially, the gut microbiota dramatically changes through interactions with the developing immune system in the gut. The process of establishing the gut microbiota is affected by various environmental factors, with the potential to be a main determinant of life-long health. In this review, we summarize recent findings regarding gut microbiota establishment, including the importance of various factors related to the development of the immune system and allergic diseases later in life.

The Role of Nutritional Aspects in Food Allergy: Prevention and Management

The prevalence of food allergy in childhood appears to be increasing in both developed and transitional countries. The aim of this paper is to review and summarise key findings in the prevention and management of food allergy, focusing on the role of dietary components and nutritional habits in the development and optimal functioning of the immune system. Essential fatty acids, zinc and vitamin D are likely to enhance the anti-inflammatory and antioxidative barrier and promote immunologic tolerance. Additionally, nutritional components such as pre- and probiotics represent a novel research approach in the attempt to induce a tolerogenic immune environment. For all these reasons, the traditional avoidance diet has been, in recent years, completely reconsidered. New findings on the protective effect of an increased diversity of food introduced in the first year of life on allergic diseases are consistent with the hypothesis that exposure to a variety of food antigens during early life might play a role in the development of immune tolerance. Accordingly, therapeutic (and even preventive) interventions should be planned on an individual basis.

Restaurant-based intervention to facilitate healthy eating choices and the identification of allergenic foods at a family-oriented resort and a campground

BACKGROUND

Restaurant-based interventions can be an enjoyable way to encourage healthier eating choices by all members of a family. Thus, the principal aims of this study were a) to promote healthy diets by increasing healthy food offerings and b) to increase the number of foods offered specifically as gluten-free and lactose-free and to inform patrons by including nutritional and allergen information that complies with Regulation 1169/2011 regarding the food served in restaurants, takeaways and snack bars.

METHODS

A restaurant-based intervention was implemented at 16 food establishments at 2 resorts (the Cambrils Park Resort and Camping Sangulí, Spain, from 2014 to 2015) based on the following 4 components: 1) providing nutritional and allergen analyses of the offered dishes, 2) increasing the number of healthy food choices, 3) identifying menu items associated with allergies and intolerance, and 4) training staff on healthy eating and allergens. Customer satisfaction regarding food aspects was assessed using surveys (10-point scale).

RESULTS

Both resorts significantly increased their offerings of healthy dishes (28.6% to 44.7%; P = 0.003) and desserts with fruit (20% to 51.3%; P = 0.013), thus obtaining the Spanish Government's Mediterranean Diet certification. Additionally, both resorts obtained Catalan Celiac Association certification. Moreover, both resorts significantly increased their percentages of gluten-free dishes (2.1% to 50.5%; P < 0.001) and lactose-free dishes (5.5% to 37.5%; P < 0.001) after the intervention. Customer satisfaction increased (mean ± standard deviation) from 6.9 ± 1.6 to 8.5 ± 1.5 (P < 0.001).

CONCLUSION

This restaurant-based intervention expanded the number of healthy and allergen-free foods offered in a family-oriented holiday resort environment to encourage healthy food choices, resulting in increased customer satisfaction.

The role of dietary interventions in the prevention of IgE-mediated food allergy in children

Over the last 30 years, the prevalence of food allergy has been on the rise and remains a disease that can have a significant impact on the quality of life of children and their families. There are several hypotheses that have been suggested to account for the increasing prevalence, but this review will focus on the impact that dietary factors have on food allergy development. In the past food allergy, prevalence has largely focused on allergen avoidance; however, there is increasing evidence from interventional studies that have shown that early introduction to potential food allergens may have a beneficial role in allergy prevention. This review aims to look at the evidence in support of early introduction of allergens into infant diets to prevent against the development of food allergy.