Prevalence and longitudinal trends of food allergy during childhood and adolescence: Results of the Isle of Wight Birth Cohort study

The Prevalence of IgE-Mediated Food Allergy and Other Allergic Diseases in the First 10 Years: The Population-Based, Longitudinal HealthNuts Study

BACKGROUND

There are limited longitudinal data on the population prevalence of allergic conditions during childhood, and few studies have incorporated the reference standard oral food challenge to confirm food allergy.

OBJECTIVE

To describe the population prevalence of IgE-mediated food allergy, eczema, asthma, and rhinitis at ages 6 and 10 years in Melbourne, Australia.

METHODS

The HealthNuts study recruited 5,276 1-year-old infants in Melbourne, Australia, with repeat assessments at ages 6 and 10 years. At ages 6 and 10 years, carers completed a questionnaire on symptoms and doctor diagnosis of allergic conditions (International Study of Asthma and Allergies in Children). Children were invited to attend a clinic assessment including skin prick test, lung function tests, and oral food challenges when indicated. To minimize the impact of attrition bias, prevalence estimates among participants at ages 6 and 10 years were weighted to reflect characteristics of the whole cohort at recruitment.

RESULTS

In total, 4,455 and 4,065 families participated at ages 6 and 10 years, respectively (84% and 77% of the original cohort). Of those, 73% and 55% of participants ages 6 and 10 years, respectively, completed clinical assessments. Overall, 36.5% (95% CI, 34.8-38.2) and 38.2% (95% CI, 36.5-40.1%) of 6- and 10-year-olds had at least one current allergic disease, and around one third of those had two or more allergic diseases. Food allergy occurred in 6.4% (95% CI, 5.6-7.2) of 6-year olds and 6.3% (95% CI, 5.5-7.2) of 10-year-olds. Among infants with challenge-confirmed food allergy in infancy, 45% had persistent disease at age 10 years. The prevalence of current diagnosed asthma at ages 6 and 10 years were 12.1% (95% CI, 10.9-13.3) and 13.1% (95% CI, 11.9-14.4), respectively, current eczema decreased slightly from 15.3% (95% CI, 14.1-19.7) at age 6 years to 12.9% (95% CI, 11.7-14.2) at age 10 years, and current rhinitis increased from 15.1% (95% CI, 13.9-16.5) at age 6 years to 25.0% (95% CI, 23.4-26.7) at age 10 years.

CONCLUSIONS

Allergic diseases affect 40% of primary school-age children; one third have multiple allergic diagnoses. Challenge-confirmed food allergy prevalence remains high, and 45% of infants with food allergy have persistent disease to age 10 years.

Understanding the burden of food allergy among urban and rural school children from north India

Background

There is paucity of reliable epidemiological data regarding the burden of food allergy in most developing countries, including India.

Objective

To provide current estimates of the prevalence and distribution of food allergy among urban and rural school children aged 6-14 years in Delhi and the National Capital Region (NCR) of Khekra in India.

Methods

A cross-sectional study was conducted from January 2022 to February 2023 to enroll school children, 6-14 years, from select urban and rural schools in Delhi and NCR. A questionnaire consisting of questions focused on household environment, early life factors, and pediatric food allergy characteristics was administered by a trained medical researcher to collect parent-proxy data. Univariate statistics were used to describe frequencies, percentages, and 95% confidence intervals for survey items.

Results

The estimated prevalence of parent-reported food allergy was 0.8% (95% CI: 0.4-1.5; urban: 0.4%, 95% CI: 0.1-1.1; rural: 1.7%, 95% CI: 0.7-3.5). Fruits such as mango (0.3%, 95% CI: 0.1-0.9), strawberry (0.1%, 95% CI: 0.0-0.7), orange (0.1%, 95% CI: 0.0-0.7), and custard apple (0.1%, 95% CI: 0.0-0.7) were reported only by urban children, while rural children reported yogurt (0.6%, 95% CI: 0.1-1.8) and wheat (0.3%, 95% CI: 0.0-1.3). Both groups reported brinjal (also known as eggplant) and banana, 0.1% (95% CI: 0.0-0.7) of urban and 0.3% (95% CI: 0.0-1.3) of rural, respectively. Overall, commonly reported clinical symptoms were diarrhea and/or vomiting (100%, 95% CI: 76.2-100), abdominal pain (88.9%, 95% CI: 58.6-98.8), and rash/itchy skin (66.7%, 95% CI: 34.8-89.6). Among children with parent reported food allergy, 66.7% (95% CI: 34.8-89.6) of food allergies were physician diagnosed, of which 33.3% were diagnosed via history alone (95% CI:7.7-71.4) while 66.7% (95% CI: 28.6-92.3) were confirmed via skin prick test and/or blood test.

Conclusion

The overall prevalence of food allergy is very low in Delhi and Khekra, India. Future work should focus on elucidating the complex interplay of early-life, environmental, genetic, and lifestyle factors to understand the reasons for India's low food allergy burden and improve epidemiological clues to prevention for the nations with higher disease burden.

Sociodemographic inequities in food allergy: Insights on food allergy from birth cohorts

A large and growing corpus of epidemiologic studies suggests that the population-level burden of pediatric FA is not equitably distributed across major sociodemographic groups, including race, ethnicity, household income, parental educational attainment, and sex. As is the case for more extensively studied allergic disease states such as asthma and atopic dermatitis epidemiologic data suggest that FA may be more prevalent among certain populations experiencing lower socioeconomic status (SES), particularly those with specific racial and ethnic minority backgrounds living in highly urbanized regions. Emerging data also indicate that these patients may also experience more severe FA-related physical health, psychosocial, and economic outcomes relating to chronic disease management. However, many studies that have identified sociodemographic inequities in FA burden are limited by cross-sectional designs that are subject to numerous biases. Compared with cross-sectional study designs or cohorts established later in life, birth cohorts offer advantages relative to other study designs when investigators seek to understand causal relationships between exposures occurring during the prenatal or postnatal period and the atopic disease status of individuals later in life. Numerous birth cohorts have been established across recent decades, which include evaluation of food allergy-related outcomes, and a subset of these also have measured sociodemographic variables that, together, have the potential to shed light on the existence and possible etiology of sociodemographic inequities in food allergy. This manuscript reports the findings of a comprehensive survey of the current state of this birth cohort literature and draws insights into what is currently known, and what further information can potentially be gleaned from thoughtful examination and further follow-up of ongoing birth cohorts across the globe.

The Natural History and Risk Factors for the Development of Food Allergies in Children and Adults

PURPOSE OF REVIEW

This narrative review explores food allergy prevalence and natural history stratified by life stages, especially in context of evolving knowledge over the last few decades.

RECENT FINDINGS

The prevalence of food allergy remains highest in early childhood with common food triggers being cow's milk, soy, hen's egg, wheat, peanut, tree nuts, sesame, fish, and shellfish. This correlates with certain risk factors especially pertinent in the postnatal period which appear to predispose an individual to developing a food allergy. Some allergies (such as milk and egg) were previously thought to be easily outgrown in early life; however, recent studies suggest increasing rates of persistence of these allergies into young adulthood; the reason behind this is unknown. Despite this, there is also evidence demonstrating that food allergies can be outgrown in adolescents and adults. An understanding of the paradigm shifts in the natural history of food allergy allows clinicians to provide updated, age-appropriate, and tailored advice for patients on the management and prognosis of food allergy.

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

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

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.

Natural history of cow's milk allergy in children aged 6-12 years

BACKGROUND

Approximately 50%-90% of children with immediate-type cow's milk allergy (CMA) acquire tolerance by pre-school age. We aimed to investigate the acquisition rate of CMA tolerance in children aged 6-12 years.

METHODS

We included children with CMA who persisted until the age of 6. Tolerance was defined as passing an oral food challenge with 200 mL of unheated cow's milk (CM) or consuming 200 mL of CM without symptoms, whereas persistent CMA was defined as fulfilling neither of these criteria by 12 years old. Children receiving oral immunotherapy (OIT) were excluded from the primary analysis. Risk factors associated with persistent CMA were assessed using Cox regression analysis.

RESULTS

Of 80 included children, 30 (38%) had previous CM anaphylaxis, and 40 (50%) had eliminated CM completely from their diet. The median CM-specific immunoglobulin E (sIgE) level at 6 years old was 12.0 kUA /L. Tolerance was acquired by 25 (31%) and 46 (58%) children by the age of 9 and 12 years, respectively. At baseline, persistent CMA was associated with higher CM-sIgE levels (hazard ratio 2.29, 95% confidence interval 1.41-3.73, optimal cutoff level 12.7 kUA /L), previous CM anaphylaxis (2.07, 1.06-4.02), and complete CM elimination (3.12, 1.46-6.67). No children with CMA who had all three risk factors (n = 14) acquired tolerance.

CONCLUSION

Except for OIT patients, more than half of children with CMA at 6 years old acquired tolerance by 12 years old. Children with CMA who have the risk factors are less likely to acquire tolerance.

Prevalence estimates of eight big food allergies in Europe: Updated systematic review and meta-analysis

In 2014, the European Academy of Allergy and Clinical Immunology published prevalence estimates for food allergy (FA) and food sensitization (FS) to the so-called eight big food allergens (i.e. cow's milk, egg, wheat, soy, peanut, tree nuts, fish and shellfish) in Europe for studies published between 2000 and 2012. The current work provides 10-year updated prevalence estimates for these food allergens. A protocol was registered on PROSPERO before starting the research (reference number CRD42021266657). Six databases were searched for studies published 2012-2021, added to studies published up to 2012, resulting in a total of 93 studies. Most studies were graded as at moderate risk of bias. The overall pooled estimates for all age groups of self-reported lifetime prevalence were as follows: cow's milk (5.7%, 95% confidence interval 4.4-6.9), egg (2.4%, 1.8-3.0), wheat (1.6%, 0.9-2.3), soy (0.5%, 0.3-0.7), peanut (1.5%, 1.0-2.1), tree nuts (0.9%, 0.6-1.2), fish (1.4%, 0.8-2.0) and shellfish (0.4%, 0.3-0.6). The point prevalence of food challenge-verified allergy were as follows: cow's milk (0.3%, 0.1-0.5), egg (0.8%, 0.5-1.2), wheat (0.1%, 0.01-0.2), soy (0.3%, 0.1-0.4), peanut (0.1%, 0.0-0.2), tree nuts (0.04%, 0.02-0.1), fish (0.02%, 0.0-0.1) and shellfish (0.1%, 0.0-0.2). With some exceptions, the prevalence of allergy to common foods did not substantially change during the last decade; variations by European regions were observed.

An Extensively Hydrolyzed Formula Supplemented with Two Human Milk Oligosaccharides Modifies the Fecal Microbiome and Metabolome in Infants with Cow's Milk Protein Allergy

Cow's milk protein allergy (CMPA) is a prevalent food allergy among infants and young children. We conducted a randomized, multicenter intervention study involving 194 non-breastfed infants with CMPA until 12 months of age (clinical trial registration: NCT03085134). One exploratory objective was to assess the effects of a whey-based extensively hydrolyzed formula (EHF) supplemented with 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT) on the fecal microbiome and metabolome in this population. Thus, fecal samples were collected at baseline, 1 and 3 months from enrollment, as well as at 12 months of age. Human milk oligosaccharides (HMO) supplementation led to the enrichment of bifidobacteria in the gut microbiome and delayed the shift of the microbiome composition toward an adult-like pattern. We identified specific HMO-mediated changes in fecal amino acid degradation and bile acid conjugation, particularly in infants commencing the HMO-supplemented formula before the age of three months. Thus, HMO supplementation partially corrected the dysbiosis commonly observed in infants with CMPA. Further investigation is necessary to determine the clinical significance of these findings in terms of a reduced incidence of respiratory infections and other potential health benefits.

The Combination of Binding Avidity of Ovomucoid-Specific IgE Antibody and Specific IgG4 Antibody Can Predict Positive Outcomes of Oral Food Challenges during Stepwise Slow Oral Immunotherapy in Children with Hen's Egg Allergy

To increase the prediction accuracy of positive oral food challenge (OFC) outcomes during stepwise slow oral immunotherapy (SS-OIT) in children with a hen's egg (HE) allergy, we evaluated the predictive value of the combination of antigen-specific IgE (sIgE) with antigen binding avidity and sIgG4 values. Sixty-three children with HE allergy undergoing SS-OIT were subjected to repeated OFCs with HE. We measured the ovomucoid (OVM)-sIgE by ImmunoCAP or densely carboxylated protein (DCP) microarray, sIgG4 by DCP microarray, and the binding avidity of OVM-sIgE defined as the level of 1/IC₅₀ (nM) measured by competitive binding inhibition assays. The OFC was positive in 37 (59%) patients undergoing SS-OIT. Significant differences in DCP-OVM-sIgE, CAP-OVM-sIgE, I/IC₅₀, DCP-OVM-sIgG4, the multiplication products of DCP-OVM-sIgE, and the binding avidity of DCP-OVM-sIgE (DCP-OVM-sIgE/IC₅₀) and DCP-OVM-sIgE/sIgG4 were compared between the negative and positive groups (p < 0.01). Among them, the variable with the greatest area under the receiver operating characteristic curve was DCP-OVM-sIgE/IC₅₀ (0.84), followed by DCP-OVM-sIgE/sIgG4 (0.81). DCP-OVM-sIgE/IC₅₀ and DCP-OVM-sIgE/sIgG4 are potentially useful markers for the prediction of positive OFCs during HE-SS-OIT and may allow proper evaluation of the current allergic status in the healing process during HE-SS-OIT.

A Meta-Analysis of the Prevalence of Wheat Allergy Worldwide

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

The epidemiology of food allergy in adults

The prevalence and awareness of food allergy (FA) among US adults is arguably at a historical high, both with respect to primary immunoglobulin E-mediated food hypersensitivity and other food-triggered conditions that operate through a variety of immunologic mechanisms (eg, pollen-FA syndrome, alpha-gal syndrome, food protein-induced enterocolitis syndrome, eosinophilic esophagitis). Worryingly, not only are many adults retaining childhood-onset food allergies as they age into adulthood, it seems that many adults are experiencing adult-onset allergies to previously tolerated foods, with correspondingly adverse physical, and psychological health impacts. Consequently, this review aims to summarize what is currently known about the epidemiology and population-level burden of FA among adult populations in North America and around the globe. This article also provides insights into the natural history of these conditions and what we need to know as we look to the future to support effective care and prevent FA.

B cell repertoire in children with skin barrier dysfunction supports altered IgE maturation associated with allergic food sensitization

The skin is a major immune organ and skin barrier dysfunction is a major risk factor for the development of the inappropriate immune response seen in allergic disease. Skin barrier disruption alters the landscape of antigens experienced by the immune system and the downstream impacts on the antibody repertoire remain poorly characterized, particularly for the IgE isotype responsible for allergic specificity and in early life, when allergic disease is developing. In this study, we sequenced antibody gene repertoires from a large and well-characterized cohort of children with atopic dermatitis and found that food sensitization was associated with lower mutation frequencies in the IgE compartment. This trend was abrogated in children living with pets during the first year of life. These results elucidate potential molecular mechanisms underlying the protective effects of pet ownership and non-antiseptic environs reported for allergic disease, and the hygiene hypothesis more broadly. We also observed increased IgE diversity and increased isotype-switching to the IgE isotype, suggesting that B cell development, particularly isotype-switching, is heavily altered in the those with food allergen sensitizations relative to those without food allergen sensitizations. Unlike for food antigens, aeroallergen sensitization exhibited no effect on IgE mutation or diversity. Consistent patterns of antibody rearrangement were associated with food allergen sensitization in subjects with atopic dermatitis. Thus, we propose the Immune Repertoire in Atopic Disease (IRAD) score, to quantify this repertoire shift and to aid clinically in patient diagnosis and risk stratification.

Frequency of food allergy in Europe: An updated systematic review and meta-analysis

Food allergy (FA) is increasingly reported in Europe, however, the latest prevalence estimates were based on studies published a decade ago. The present work provides the most updated estimates of the prevalence and trends of FA in Europe. Databases were searched for studies published between 2012 and 2021, added to studies published up to 2012. In total, 110 studies were included in this update. Most studies were graded as moderate risk of bias. Pooled lifetime and point prevalence of self-reported FA were 19.9% (95% CI 16.6-23.3) and 13.1% (95% CI 11.3-14.8), respectively. The point prevalence of sensitization based on specific IgE (slgE) was 16.6% (95% CI 12.3-20.8), skin prick test (SPT) 5.7% (95% CI 3.9-7.4), and positive food challenge 0.8% (95% CI 0.5-0.9). While lifetime prevalence of self-reported FA and food challenge positivity only slightly changed, the point prevalence of self-reported FA, sIgE and SPT positivity increased from previous estimates. This may reflect a real increase, increased awareness, increased number of foods assessed, or increased number of studies from countries with less data in the first review. Future studies require rigorous designs and implementation of standardized methodology in diagnosing FA, including use of double-blinded placebo-controlled food challenge to minimize potential biases.

Prevalence of Parent-Reported Food Allergies and Associated Risk Predictors Among Children in Saudi Arabia

BACKGROUND AND OBJECTIVE

The worldwide prevalence of food allergies has been increasing recently. Due to limited data on food allergy (FA) in Saudi Arabia, this study was conducted to estimate the prevalence and risk factors of parent-reported food allergies and clinical manifestations in children in Taif, Saudi Arabia.

METHODOLOGY

A cross-sectional questionnaire-based observational study was conducted from July 2019 to December 2020. A total of 508 parents of school children (aged five to eight years) responded to the questions based on the child's health and food allergies.

RESULTS

FA (16.1%) was observed as the most common type of allergy among children. The prevalence of other atopic diseases was estimated at 30.5%. The most common allergy-causing foods were eggs (4.9%), peanuts (2.7%), and sesame (2.5%). Rash, itching without rash, and vomiting were the most common FA symptoms. The presence of childhood eczema (p< 0.0001), allergic rhinitis (p= 0.005), and the father's history of allergy (p= 0.005) were all significant and independent predictors/risk factors for FA among the studied children.

CONCLUSION

We noted substantial parents' concern with food allergies among children in Saudi Arabia, which necessitates the establishment of effective diagnosis and treatment strategies and primary prevention initiatives.

Narcolepsy-Like Sleepiness: A Symptom of Immediate-Type Reactions in Food-Allergic Children

BACKGROUND

It has been reported that sometimes children fall asleep and can barely be woken up during allergic reactions on food ingestion. Nevertheless, to date, there is scarce data on narcolepsy-like sleepiness as a symptom of allergic reactions.

OBJECTIVE

To investigate the frequency of narcolepsy-like sleepiness during oral food challenges and characterize this symptom regarding comorbidities, eliciting allergens, and severity of reactions.

METHODS

Children with immediate-type allergic reactions during oral food challenges (89% were double-blind, placebo-controlled) have been analyzed in this study. Narcolepsy-like sleepiness was defined as a somnolent condition during which patients could barely be woken up again, occurring within 2 hours of food intake and which was not due to drug side effects. Logistic generalized estimating equations were used to explore the effect of age, severity of reactions, and eliciting allergens on the occurrence of narcolepsy-like sleepiness.

RESULTS

In 106 (12.5%) of all 848 food-allergic children, narcolepsy-like sleepiness was observed during oral food challenges. Children with eczema had a higher risk of developing narcolepsy-like sleepiness (P = .006). Narcolepsy-like sleepiness occurred most often due to an allergic reaction to hazelnut (P = .009) or other tree nuts (P = .003). Moderate to severe reactions occurred more often than mild reactions (P = .026; odds ratio, 1.521; 95% CI, 1.051-2.202) in children with narcolepsy-like sleepiness.

CONCLUSIONS

We were able to show for the first time that narcolepsy-like sleepiness is a frequently occurring clinical manifestation of immediate-type allergic reactions on food ingestion in childhood. Further research is needed to unravel the underlying mechanisms to gain a deeper insight into this underestimated symptom.

Exploration of Specific Nanobodies As Immunological Reagents to Detect Milk Allergen of β-Lactoglobulin without Interference of Hydrolytic Peptides

Milk proteins are widely used for food supplementation, despite the potential risk of food allergy, especially against β-lactoglobulin (BLG), which makes BLG surveillance critical. Possible interaction of detecting antibodies with BLG-derived peptides will result in unprecise inspection. Thus, in this study, it was proposed to generate nanobodies (Nbs) and validate the immunological detection of intact BLG rather than hydrolytic peptides. Nbs were successfully retrieved and characterized with high stability and target specificity. A competitive enzyme-linked immunosorbent assay (cELISA) was developed with a linear range from 39 to 10,000 ng/mL and a detection limit (LOD) of 4.55 ng/mL, with a recovery of 86.30%-95.09% revealed by analysis of spiked samples. Meanwhile, a sandwich ELISA (sELISA) was established with Nb82 and BLG polyclonal antibody (pAb-BLG) providing a linear range from 29.7 to 1250 ng/mL and an LOD of 13.82 ng/mL with a recovery of 87.82%-103.97%. The interaction of selected Nbs with BLG-derived peptides was investigated by Nb structure modeling and BLG docking. No binding on hydrolytic peptides was revealed, confirming the precision of Nb-mediated immunoassays. In summary, this study successfully identified BLG-specific Nbs for immunoassay development and guaranteed the monitoring of intact BLG without interference of hydrolytic peptides, providing experimental evidence that our Nbs recognize intact food allergen.

Prevalence of Food Allergy in France up to 5.5 Years of Age: Results from the ELFE Cohort

Background: In France, updated data on food allergies (FAs) are lacking, despite the need for efficient FA management and prevention. This study aimed to evaluate the prevalence of FAs in children in France, describe the most common allergens and determine the prevalence of atopic diseases in children with FAs. Methods: The ELFE study comprises a French nationwide birth cohort, including 18,329 children born in 2011. FAs were assessed by parental reports of food avoidance based on medical advice related to FAs, provided at 2 months and 2, 3.5 and 5.5 years of age. Data regarding FAs were available for 16,400 children. Data were weighted to account for selection and attrition bias. Results: From birth to 5.5 years of age, FAs were reported for 5.94% (95% CI: 5.54–6.34) children. Milk was the most common allergen, followed by egg, peanut, exotic fruits, tree nuts, gluten and fish. Among children with FAs, 20.5% had an allergy to at least two different groups of allergens; 71% reported eczema at least once before 5.5 years of age; 24.4% reported incidence of asthma; and 42.3% reported incidence of allergic rhinitis or conjunctivitis. Conclusion: In France, the prevalence of FAs in children up to 5.5 years of age is approximately 6%. It was demonstrated that 1 in 5 children with allergies had multiple FAs.

The natural history of peanut and egg allergy in children up to age 6 years in the HealthNuts population-based longitudinal study

BACKGROUND

Prospectively collected data on the natural history of food allergy are lacking.

OBJECTIVE

We examined the natural history of egg and peanut allergy in children from age 1 to 6 years and assessed whether a skin prick test (SPT) result or other clinical factors at diagnosis are associated with the persistence or resolution of food allergy in early childhood.

METHODS

The HealthNuts cohort consists of 5276 children who were recruited at age 1 year and have been followed prospectively. Children with food allergy at age 1 year (peanut [n = 156] or raw egg [n = 471] allergy ) and children who developed new sensitizations or food reactions after age 1 year were assessed for food sensitization and allergy (confirmed by oral food challenge when indicated) at the 6-year follow-up.

RESULTS

New-onset food allergy developed by age 6 years was more common for peanut (0.7% [95% CI = 0.5%-1.1%]) than egg (0.09% [95% CI = 0.03%-0.3%]). Egg allergy resolved more commonly (89% [95% CI = 85%-92%]) than peanut allergy (29% [95% CI = 22%-38%]) by age 6 years. The overall weighted prevalence of peanut allergy at age 6 years was 3.1% (95% CI = 2.6-3.7%) and that of egg allergy was 1.2% (95% = CI 0.9%-1.6%). The factors at age 1 year associated with persistence of peanut allergy were peanut SPT result of 8 mm or larger (odds ratio [OR] = 2.35 [95% CI 1.08-5.12]), sensitization to tree nuts (adjusted OR [aOR] = 2.51 [95% CI = 1.00-6.35]), and early-onset severe eczema (aOR = 3.23, [95% CI 1.17-8.88]). Factors at age 1 associated with persistence of egg allergy at age 6 were egg SPT result of 4 mm or larger (OR = 2.98 [95% CI 1.35-6.36]), other (peanut and/or sesame) food sensitizations (aOR = 2.80 [95% CI = 1.11-7.03]), baked egg allergy (aOR = 7.41 [95% CI = 2.16-25.3]), and early-onset severe eczema (aOR = 3.77 [95% CI = 1.35-10.52]).

CONCLUSION

Most egg allergy and nearly one-third of peanut allergy resolves naturally by age 6 years. The prevalence of peanut allergy at age 6 years was similar to that observed at age 1 year, largely owing to new-onset food peanut allergy after age 1 year. Infants with early-onset eczema, larger SPT wheals, or multiple food sensitizations and/or allergies were less likely to acquire tolerance to either peanut or egg.

Egg Allergy in Children and Weaning Diet

Eggs are a fundamental food in the human diet, and together with cow’s milk, they are the most common food allergen. This work highlights the main nutritional characteristics of eggs to show how their absence from a child’s diet can constitute a serious deficiency. We then analyze the risk factors that facilitate the onset of egg allergy. The third part of the paper reports possible interventions to lower the appearance of food allergy that have been occurred in trials. The last part of the paper is a synthesis of this research study that has been taken from several of the latest guidelines or from position papers.

The US population-level burden of cow's milk allergy

Background

Cow's milk is a food allergen of public health importance both in the United States and globally. Its natural history and epidemiology have been most studied among infants and young children, but the public health burden it places on adults and older pediatric populations remains unclear. This study comprehensively characterizes the US population-level burden of cow's milk allergy (CMA), including its prevalence, severity, health care utilization, psychosocial impact, natural history, and other associated factors-including ability to tolerate extensively heated milk products-within a large, nationally-representative survey sample of US households.

Methods

A cross-sectional survey was administered via web and telephone. Population level inference was based on data collected from participants recruited from National Opinion Research Center (NORC) at the University of Chicago's probability-based AmeriSpeak panel. Established dual-sample complex survey calibration methods were used to augment this sample with additional participants recruited through Survey Sampling International to increase the precision of the resulting estimates. In total, surveys were administered to a nationally representative sample of 51 819 US households from October 1, 2015, through September 31, 2016. Self-report responses from 40 453 adults and parent-proxy report for 38 408 children were analyzed.

Results

Analyzing survey responses from 78 851 individuals, an estimated 4.7% (95% CI, 4.4%-4.9%) of the US population reported current CMA, whereas 1.9% (95% CI, 1.8%-2.1%) met symptom-report criteria for convincing IgE-mediated allergy. An estimated 0.9% (95% CI, 0.8%-1.0%) had CMA that met convincing symptom-report criteria and was physician diagnosed. Female and White respondents were more likely to report outgrowing CMA relative to males and those reporting other races and ethnicities. Individuals with CMA who reported tolerance to baked milk products were less likely to report severe reaction histories (33.5% vs 42.7%; p = .03), a lifetime history of food allergy-related emergency department visits (43.4% vs. 55.8%; p = .005), and treating a milk-allergic reaction with epinephrine (10.6 vs. 18.9%; p = .003). These individuals also exhibited less psychosocial burden on the validated Food Allergy Independent Measure (FAIM) than their counterparts with CMA who were allergic to baked forms of milk.

Conclusion

These data indicate a discrepancy in reported rates of allergy to cow's milk among the US general population ranging from approximately 1 in 20 with reported CMA to fewer than 1 in 50 with physician-confirmed CMA. However, they suggest a substantial population-level burden of CMA, including substantial healthcare utilization, psychosocial burden and nutritional impacts-particularly among the approximately 30% of individuals with CMA who cannot tolerate baked forms of milk.

Food Allergy Education and Management in Schools: A Scoping Review on Current Practices and Gaps

Currently, no synthesis of in-school policies, practices and teachers and school staff’s food allergy-related knowledge exists. We aimed to conduct a scoping review on in-school food allergy management, and perceived gaps or barriers in these systems. We conducted a PRISMA-ScR-guided search for eligible English or French language articles from North America, Europe, or Australia published in OVID-MedLine, Scopus, and PsycINFO databases. Two reviewers screened 2010 articles’ titles/abstracts, with 77 full-text screened. Reviewers differed by language. Results were reported descriptively and thematically. We included 12 studies. Among teachers and school staff, food allergy experiences, training, and knowledge varied widely. Food allergy experience was reported in 10/12 studies (83.4%); 20.0–88.0% had received previous training (4/10 studies; 40.0%) and 43.0–72.2% never had training (2/10 studies; 20.0%). In-school policies including epinephrine auto-injector (EAI) and emergency anaphylaxis plans (EAP) were described in 5/12 studies (41.7%). Educational interventions (8/12 studies; 66.7%) increased participants’ knowledge, attitudes, beliefs, and confidence to manage food allergy and anaphylaxis vs. baseline. Teachers and school staff have more food allergy-related experiences than training and knowledge to manage emergencies. Mandatory, standardized training including EAI use and evaluation, and the provision of available EAI and EAPs may increase school staff emergency preparedness.

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

Background

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

Objective

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

Methods

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

Results

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

Conclusion

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

An Electrochemical Molecularly Imprinted Polymer Sensor for Rapid β-Lactoglobulin Detection

Facile detection of β-lactoglobulin is extraordinarily important for the management of the allergenic safety of cow's milk and its dairy products. A sensitive electrochemical sensor based on a molecularly imprinted polymer-modified carbon electrode for the detection of β-lactoglobulin was successfully synthesized. This molecularly imprinted polymer was prepared using a hydrothermal method with choline chloride as a functional monomer, β-lactoglobulin as template molecule and ethylene glycol dimethacrylate as crosslinking agent. Then, the molecularly imprinted polymer was immobilized on polyethyleneimine (PEI)-reduced graphene oxide (rGO)-gold nanoclusters (Au-NCs) to improve the sensor's selectivity for β-lactoglobulin. Under optimal experimental conditions, the designed sensor showed a good response to β-lactoglobulin, with a linear detection range between 10-9 and 10-4 mg/mL, and a detection limit of 10-9 mg/mL (S/N = 3). The developed electrochemical sensor showed a high correlation in the detection of β-lactoglobulin in four different milk samples from the market, indicating that the sensor can be used with actual sample.

The Interplay of Nutriepigenomics, Personalized Nutrition and Clinical Practice in Managing Food Allergy

Food allergy in children has been a common issue due to the challenges of prescribing personalized nutrition with a lack of nutriepigenomics data. This has indeed further influenced clinical practice for appropriate management. While allergen avoidance is still the main principle in food allergy management, we require more information to advance the science behind nutrition, genes, and the immune system. Many researchers have highlighted the importance of personalized nutrition but there is a lack of data on how the decision is made. Thus, this review highlights the relationship among these key players in identifying the solution to the clinical management of food allergy with current nutriepigenomics data. The discussion integrates various inputs, including clinical assessments, biomarkers, and epigenetic information pertaining to food allergy, to curate a holistic and personalized approach to food allergy management in particular.

A case-control study of respiratory medication and co-occurring gastrointestinal prescription burden among persons with Ehlers-Danlos syndromes

We previously reported increased pain and gastrointestinal (GI) medication prescription claims among persons with Ehlers-Danlos syndromes (EDS) and peripubertal increase in opioid and anti-emetic claims among women with EDS. Herein, we hypothesized a higher proportion of respiratory and co-occurring respiratory and GI medication prescription claims among persons with EDS compared to their matched controls with increases among peripubertal women with EDS. We compared the proportions of respiratory and co-occurring respiratory and GI medication prescription claims among persons with EDS (aged 5-62) against their age-, sex-, state of residence-, and earliest claim date-matched controls using 10 years of private prescription claims data. Prescription claims among persons with EDS versus matched controls were increased for eight medication classes (p < .0001): intranasal/inhaled corticosteroids (ICS) (30.8% vs. 19.0%), oral steroids (30.0% vs. 16.5%), H1-antihistamines (26.2% vs. 12.2%), short-acting beta agonists (22.7% vs. 11.6%), decongestants (21.6% vs. 15.9%), leukotriene modifiers (8.9% vs. 3.6%), ICS/long-acting beta agonists (5.7% vs. 2.9%), muscarinic antagonists (2.5% vs. 0.9%), and co-occurring prescriptions (29% vs. 10%). Our results suggest a critical time window for peripubertal intervention and research and a need to focus on the pathogenesis and clinical evaluation of EDS-specific respiratory and aerodigestive disorders.

Dissemination of EAACI food allergy guidelines using a flexible, practical, whole school allergy awareness toolkit

BACKGROUND

Essential training for emergency adrenaline auto-injector administration alone provides an inadequate safeguard in school environments. Recent UK deaths have reinforced the urgency for embedding whole school (WS) allergy awareness to minimise risk. We documented the development of a practical, flexible WS Food Allergy Awareness Toolkit for UK secondary schools.

METHODS

We used a multidisciplinary participatory action research methodology, involving successive modification and retesting of a pragmatic toolkit in 3 case study schools. A School Allergy Action Group drives WS risk assessment, helping schools gradually implement best practice policy in line with their particular needs. Additional schools self-piloted the resulting toolkit with only remote monitoring. School surveys, based on EAACI guidelines were developed to identify priorities and assess change.

RESULTS

Effectiveness of the resulting process toolkit, now available online, was independently demonstrated via pre/post-intervention questionnaires from 24/10 pupils with food allergy (FA) and 97/6 pupils without FA, respectively. Pearson correlational analysis showed strong negative relationships between Food Allergy Quality of Life Questionnaire (FAQLQ) at T0 and School Support (SS) at T0 (r = -0.8, P<0.01), and between SS and Self-Efficacy (SE) (r = 0.73, P<0.05). Mean FAQLQ scores improved between T0 (3.3) and T1 (2.5). SE improved for those with FA (mean difference = 1.0). In those without FA, SE (mean difference = 0.9) and Attitudes and Knowledge (mean difference = 0.7) also improved.

CONCLUSIONS

Full stakeholder involvement in toolkit development encourages usage and, therefore, improves WS community awareness; reduces risk of reactions; fosters a more accepting societal attitude and empowers pupils with/without allergies to self-manage effectively.

Childhood food allergy and food allergen sensitisation are associated with adult airways disease: A birth cohort study

BACKGROUND

Childhood food allergy (FA) and food allergen sensitization (FAS) are associated with allergic airway disease(s) [AAD] (asthma and rhinitis) in childhood. However, the associations between childhood FA/FAS and AAD in adulthood are not well described.

METHODS

We investigated the longitudinal relationship between childhood FA/FAS to common food allergens and AAD at 18 and 26 years, in the Isle of Wight birth cohort. Study subjects (N = 1456) were followed up at fixed time points from ages 1-26 years for FA/FAS status. AAD were evaluated from 4 years onwards. The associations between FA/FAS and AAD were assessed with univariate analyses and then multivariable logistic regression, adjusting for clinically relevant co-variates.

RESULTS

Food allergy at 4 years was significantly associated with asthma at 18 years [adjusted odds ratio (aOR): 2.75, 95% CI: 1.53-4.92, p = .001] and 26 years (aOR: 2.62, 95% CI: 1.32-5.20, p = .006). Conversely, childhood FA was not associated with adulthood rhinitis whatsoever. While FAS at ages 4 and 10 were associated with both AAD, the associations between FAS and rhinitis were less robust relative to asthma.

CONCLUSION

Childhood FA increased the odds of asthma during adulthood by nearly threefold. Additionally, childhood FAS was also associated with increased odds of asthma in adulthood. Conversely, FAS but not FA in childhood was associated with rhinitis in adulthood. We suggest that children with FA/FAS should be followed up to facilitate early detection and intervention of subsequent AAD, particularly asthma.

Lactobacillus rhamnosus GG for Cow's Milk Allergy in Children: A Systematic Review and Meta-Analysis

Objective: Cow's milk allergy (CMA) is a common allergic disease. Probiotics have been suggested as a treatment for CMA, with Lactobacillus rhamnosus GG (LGG) being one of the important predominant choices. Despite reports on this topic, the effectiveness of application in CMA remains to be firmly established. Methods: To assess the effects of LGG on CMA in children, the PubMed/Medline, Embase, Cochrane Library, and Web of Science databases were searched for studies on LGG in treatment of CMA, which were published in the English language. Results: Ten studies were finally included. Significantly higher tolerability rates favoring LGG over controls were observed [risk ratio (RR), 2.22; 95% confidence interval (CI), 1.86-2.66; I 2 = 0.00; moderate-quality evidence]. There were no significant differences in SCORAD values favoring LGG over the placebo (mean difference, 1.41; 95% CI, -4.99-7.82; p = 0.67; very low-quality evidence), and LGG may have improved fecal occult blood (risk ratio, 0.36; 95% CI, 0.14-0.92; p = 0.03; low-quality evidence). Conclusion: We found that LGG may have moderate-quality evidence to promote oral tolerance in children with CMA and may facilitate recovery from intestinal symptoms. However, this finding must be treated with caution, and more gpowerful RCTs are needed to evaluate the most effective dose and treatment time for children with CMA. Registration number: CRD42021237221.

IgE-mediated fish allergy in children: is omega-3 supplementation useful?

The management of fish allergy relies on the elimination of all fish from the diet. Nevertheless, an exclusion diet can be problematic from a paediatric nutritional perspective. The issue of a substitute diet for children suffering from fish allergy seems to be not adequately addressed and the consequences of a fish exclusion diet in paediatric age are not known. Fish has an important nutritional value, it is rich in vitamins of group B, D and A, selenium, calcium and phosphorus, iron, zinc, magnesium, iodine and omega-3. While vitamins and iodine are normally present in the diet, omega-3 is present in few other foods, such as vegetable seed oils and nuts. Hence, the scientific research indicates a generic advice regarding a possible omega-3 supplementation in children with fish allergy. Given the knowledge about omega-3 supplementation having a potential good risk-benefit ratio and the absence of serious adverse events related to the omega-3 supplementation, this type of supplementation may seem advisable in children affected by fish allergy.

Growth in Infants with Cow's Milk Protein Allergy Fed an Amino Acid-Based Formula

PURPOSE

The present study assessed the role of an amino acid-based formula (AAF) in the growth of infants with cow's milk protein allergy (CMPA).

METHODS

Non-breastfed, term infants aged 0-6 months with symptoms suggestive of CMPA were recruited from 10 pediatric centers in China. After enrollment, infants were started on AAF for two weeks, followed by an open food challenge (OFC) with cow's milk-based formula (CMF). Infants with confirmed CMPA remained on AAF until 9 months of age, in conjunction with a cow's milk protein-free complementary diet. Body weight, length, and head circumference were measured at enrollment and 9 months of age. Measurements were converted to weight-for-age, length-for-age, and head circumference-for-age Z scores (WAZ, LAZ, HCAZ), based on the World Health Organization growth reference.

RESULTS

Of 254 infants (median age 16.1 weeks, 50.9% male), 218 (85.8%) were diagnosed with non-IgE-mediated CMPA, 33 (13.0%) tolerated CMF, and 3 (1.2%) did not complete the OFC. The mean WAZ decreased from 0.119 to -0.029 between birth and enrollment (p=0.067), with significant catch-up growth to 0.178 at 9 months of age (p=0.012) while being fed the AAF. There were no significant changes in LAZ (0.400 vs. 0.552; p=0.214) or HCAZ (-0.356 vs. -0.284; p=0.705) from the time of enrollment to age 9 months, suggesting normal linear and head growth velocity.

CONCLUSION

The amino acid-based study formula, in conjunction with a cow's milk protein-free complementary diet, supported normal growth till 9 months of age in a cohort of Chinese infants with challenge-confirmed non-IgE-mediated CMPA.

Current transition management of adolescents and young adults with allergy and asthma: a European survey

Background

Transition from parent-delivered to self-management is a vulnerable time for adolescents and young adults (AYA) with allergy and asthma. There is currently no European guideline available for healthcare professionals (HCPs) on transition of these patients and local/national protocols are also mostly lacking.

Methods

European HCPs working with AYA with allergy and asthma were invited to complete an online survey assessing challenges of working with these patients, current transition practices and access to specific healthcare resources.

Results

A total of 1179 responses from 41 European countries were collected. Most HCPs (86%) reported a lack of a transition guideline and a lack of a transition process (20% paediatric HCPs, 50% of adult HCPs, 56% HCP seeing all ages). Nearly half (48%) acknowledged a lack of an established feedback system between paediatric and adult medical services. Many respondents never routinely asked about mental health issues such as self-harm or depression and are not confident in asking about self-harm (66.6%), sexuality (64%) and depression (43.6%). The majority of HCPs (76%) had not received specific training in the care of AYA although 87% agreed that transition was important for AYA with allergy and asthma.

Conclusion

Although there was agreement that transition is important for AYA with allergy and asthma, there are crucial limitations and variations in the current provision of transition services across Europe. Standardisation of AYA management and specific training are required. This should improve management and continuity of care during adolescence and into adulthood to achieve the best healthcare outcomes.

Egg Allergy in US Children

BACKGROUND

Egg allergy is common in young children (<5 years) and has significant negative impacts on quality of life.

OBJECTIVE

The objective of this study was to characterize egg allergy prevalence, severity, baked egg tolerance, and other associated factors in a large US cohort.

METHODS

A national cross-sectional survey was administered from October 2015 to September 2016, resulting in complete parent-proxy responses for 38,408 children. Weighted proportions were estimated to compare egg allergy prevalence and characteristics between key subpopulations.

RESULTS

The overall prevalence of current, convincingly egg allergy was 0.9% among all children and 1.3% among children <5 years. Black children were over-represented among children with egg allergy, accounting for 23.4% (95% confidence interval: 13.1-38.4) of egg-allergic children despite comprising 13.2% (12.3-14.2) of the US pediatric population. Among children with egg allergy, 64.2% reported baked egg tolerance and 60.2% had allergy to other foods, with 29.3% having peanut allergy. Asthma was more prevalent in children with an egg allergy than children with other top 8 food allergies (46.5% [35.8-57.4] vs 33.2% [29.6-37.0], P < .05). Among children with current egg allergy, those with baked egg tolerance reported that their food allergy resulted in significantly reduced psychosocial burden, relative to their baked egg-allergic counterparts (M = 3.1 [2.9-3.3] vs M = 3.7 [3.5-3.9]).

CONCLUSIONS

Egg allergy is common amongst young children. Nearly two-thirds of children with egg allergy reported baked egg tolerance. Increased efforts are needed to ensure that children with egg allergy are appropriately evaluated as many have comorbid allergic disease and determination of baked egg tolerance may improve quality of life.

Oral immunotherapy for peanut allergy: The con argument

Background

In some countries of the world, peanut allergy represents an important source of anaphylactic reactions. Traditionally treated with the avoidance of responsible allergens, this condition can also be targeted by oral peanut immunotherapy.

Methods

In this study, we review the beneficial and side effects of currently available forms of peanut oral immunotherapy (POIT). We report the discussions resulting from the publication of a meta-analysis that brought to light the downsides of oral immunotherapy for peanuts.

Results

In some clinical situations, the risk-benefit ratio can favor peanut oral immunotherapy over avoidance. In many other situations, this is not the case. The decision must be based on the values and preferences of clinicians and patients. Those not ready to accept serious adverse effects from POIT are likely to continue the elimination diet; those motivated to achieving desensitization, and prepared to accept serious adverse effects, may choose to undergo POIT.

Conclusions

Without being prejudiced against peanut oral immunotherapy, we indicate the possible evolution of treatment for this condition is in a rapidly evolving broader scenario. Among the future options, sublingual immunotherapy, parenteral immunotherapy with modified allergens, transcutaneous immunotherapy, and the use of biologics will become important options.

Developments in the field of clinical allergy in 2018 through the eyes of Clinical and Experimental Allergy, Part II

In this article, we describe developments in the field of clinical allergy as described by Clinical and Experimental Allergy in 2018; epidemiology, asthma and rhinitis, clinical allergy and allergens are all covered.

Association of Cow's Milk Protein Allergy Prevalence With Socioeconomic Status in a Cohort of Chilean Infants

OBJECTIVES

The aim of the study was to compare the cow's milk protein allergy (CMPA) prevalence in 2 cohorts of children from different socioeconomic strata.

METHODS

Prospective birth cohort that included patients from 2 hospitals providing care for a low- and high-income population, respectively. Healthy newborns ≥34 gestational weeks were recruited and followed up to 12 months by a monthly telephone survey. If ≥2 predefined symptoms/signs suggestive of CMPA were detected, the patient was evaluated by a pediatric gastroenterologist. Diagnosis was confirmed by exclusion diet followed by open oral food challenge.

RESULTS

Overall the prevalence of CMPA was 5.2%, with a 6 times higher prevalence in the high income cohort (9.2%) compared with the low-income group (1.5%; relative risk 6.2; 95% confidence interval 1.8-20.7; P = 0.0005). All the cases were non-immunoglobulin E-mediated with predominantly gastrointestinal symptoms. High-income cohort did have higher frequency of C-section, mother's previous chronic disease, mother's history of atopy/food allergy, older age, and higher educational level of parents. Parent smoking and presence of pets at home were more frequent in the low-income cohort. Multiple logistic regression showed that the high-income cohort did have older age and higher educational level of both parents.

CONCLUSION

In these cohorts the prevalence of CMPA was higher than reported previously in other developing countries and significantly higher in the high-income group. Our findings were associated with sociodemographic characteristics of the parents.

The Sesame-Peanut Conundrum in Israel: Reevaluation of Food Allergy Prevalence in Young Children

BACKGROUND

Food allergies (FAs) are on the rise worldwide. A previous cross-sectional study from 2002 in Israel estimated the prevalence of IgE-mediated FA among young children at 0.85%. Although sesame was found to be a common allergen, peanuts were found to be a rare allergen.

OBJECTIVE

To determine the prevalence and distributions of IgE-mediated FAs among young children in Israel compared with previous data.

METHODS

A total of 1932 young children (56% males, 44% females) with a mean age of 22.4 months (range, 18-30 months) were sequentially recruited from 15 government family health care centers in north Israel. Parents completed a questionnaire with 2 screening questions for suspected FA. Subjects with suspected FA underwent further evaluation including telephone interview, skin prick tests, and oral food challenge as needed.

RESULTS

After analyzing the questionnaires, 146 subjects were suspected to have FA. Seventy-nine subjects were excluded by telephone interview and 13 were excluded on the basis of negative oral food challenge. We identified 54 of 1932 (2.8%) young children with 75 IgE-mediated FAs. Thirty-nine of 54 (72.2%) had allergy to 1 food and 9 (16.6%) to 2 foods. The most common food allergens were cow's milk (1%), eggs (0.88%), sesame (0.93%), tree nuts (0.57%), peanuts (0.2%), and fish (0.2%).

CONCLUSIONS

The prevalence of IgE-mediated FA among young children in Israel has increased dramatically from 0.85% to 2.8%. The relative prevalence of the most common food allergens is similar to that identified in 2002, with a high prevalence of sesame FA and low prevalence of peanut FA.

Prevalence of Food Sensitization and Food Allergy in Children Across Europe

BACKGROUND

For adults, prevalence estimates of food sensitization (FS) and food allergy (FA) have been obtained in a standardized manner across Europe. For children, such estimates are lacking.

OBJECTIVES

To determine the prevalence of self-reported FA, FS, probable FA (symptoms plus IgE sensitization), and challenge-confirmed FA in European school-age children.

METHODS

Data on self-reported FA were collected through a screening questionnaire sent to a random sample of the general population of 7- to 10-year-old children in 8 European centers in phase I of the EuroPrevall study. Data on FS and probable FA were obtained in phase II, comprising an extensive questionnaire on reactions to 24 commonly implicated foods, and serology testing. Food challenge was performed in phase III.

RESULTS

Prevalence (95% CI) of self-reported FA ranged from 6.5% (5.4-7.6) in Athens to 24.6% (22.8-26.5) in Lodz; prevalence of FS ranged from 11.0% (9.7-12.3) in Reykjavik to 28.7% (26.9-30.6) in Zurich; and prevalence of probable FA ranged from 1.9% (0.8-3.5) in Reykjavik to 5.6% (3.6-8.1) in Lodz. In all centers, most food-sensitized subjects had primary (non-cross-reactive) FS. However, FS due to birch pollen related cross-reactivity was also common in Central-Northern Europe. Probable FA to milk and egg occurred frequently throughout Europe; to fish and shrimp mainly in the Mediterranean and Reykjavik. Peach, kiwi, and peanut were prominent sources of plant FA in most countries, along with notably hazelnut, apple, carrot, and celery in Central-Northern Europe and lentils and walnut in the Mediterranean.

CONCLUSIONS

There are large geograhical differences in the prevalence of FS and FA in school-age children across Europe. Both primary and cross-reactive FS and FA occur frequently.

Overcoming Shellfish Allergy: How Far Have We Come?

Shellfish allergy caused by undesirable immunological responses upon ingestion of crustaceans and mollusks is a common cause of food allergy, especially in the Asia-Pacific region. While the prevalence of shellfish allergy is increasing, the mainstay of clinical diagnosis for these patients includes extract-based skin prick test and specific IgE measurement while clinical management consists of food avoidance and as-needed use of adrenaline autoinjector should they develop severe allergic reactions. Such a standard of care is unsatisfactory to both patients and healthcare practitioners. There is a pressing need to introduce more specific diagnostic methods, as well as effective and safe therapies for patients with shellfish allergy. Knowledge gained on the identifications and defining the immuno-molecular features of different shellfish allergens over the past two decades have gradually translated into the design of new diagnostic and treatment options for shellfish allergy. In this review, we will discuss the epidemiology, the molecular identification of shellfish allergens, recent progress in various diagnostic methods, as well as current development in immunotherapeutic approaches including the use of unmodified allergens, hypoallergens, immunoregulatory peptides and DNA vaccines for the prevention and treatment of shellfish allergy. The prospect of a “cure “for shellfish allergy is within reach.

Nutritional Issues in Food Allergy

Diet and nutrition play an important role in the development and management of food allergy. The diet of expectant mothers can have an effect on their offspring in terms of allergic outcomes. A host of confounding factors may influence this, with a maternal diet rich in fruits and vegetables, fish, vitamin D-rich foods associated with a lower risk of allergic disease in their children. More surprisingly, the consumption of milk and butter has also been shown to have a protective effect, especially in a farm environment. Similarly, the diet of the infant can also be important, not only in terms of breast feeding, but also the timing of the introduction of complementary foods, the diversity of the diet and the effect of individual foods on the development of allergy. One factor which has clearly been shown not to influence the development of food allergy is allergen avoidance by expectant mothers. In the infant diet, the manipulation of the gut microbiome to prevent the development of atopic disease is clearly an area which promises much, although studies have yet to provide a breakthrough in the prevention of atopic dermatitis. More concrete evidence of the value of diet in prevention has come from studies evaluating infant eating patterns which may protect gut health, through the consumption of large amounts of home-processed fruits and vegetables. The consumption of fish during the first year of life has also been shown to be protective. The importance of nutritional issues in children and adults who have a food allergy has become much more accepted in recent years. The primary allergenic foods in infancy and childhood, milk, egg, wheat and soy are also ones which are present in many foods and thus their avoidance can be problematic from a nutritional perspective. Thus, children with a food allergy can have their growth compromised through avoidance, especially pre-diagnosis, when foods may be excluded without any expert nutritional input. The management of a food allergy largely remains the exclusion of the offending food(s), but it is now clear that in doing so, children in particular can be at nutritional risk if insufficient attention is paid to the rest of the diet. Adults with food allergy are often thought not to need nutritional counselling; however, many will exclude a wide range of foods due to anxiety about trace exposure, or similar foods causing reactions. The avoidance of staple foods such as milk and wheat are common, but substitute foods very often do not have comparable nutritional profiles. Adults may also be more susceptible to on-line promotion of extreme nutritional regimes which can be extremely harmful. All food allergic individuals, whatever their age, should have a nutrition review to ensure they are consuming a healthy, balanced diet, and are not avoiding food groups unnecessarily.

Eczema phenotypes and risk of allergic and respiratory conditions in school age children

Background

Eczema phenotypes based on eczema onset and persistence might better identify groups prone to allergic and respiratory conditions than a binary definition of eczema. We examined the associations of childhood eczema phenotypes with allergic sensitization, allergy, asthma and lung function at school age.

Methods

This study among 4277 children was embedded in a multi-ethnic population-based prospective cohort study. Five eczema phenotypes (never, early transient, mid-transient, late transient, persistent) based on parental-reported physician-diagnosed eczema from age 6 months until 10 years were identified. At age 10 years, allergic sensitization was measured by skin prick tests, physician-diagnosed allergy and asthma by parent-reported questionnaires, and lung function by spirometry. Adjusted linear, logistic and multinomial regression models were applied.

Results

Compared with never eczema, all eczema phenotypes were associated with increased risks of asthma (odds ratios (OR) range (95% confidence interval): 2.68 (1.58, 4.57) to 11.53 (6.65, 20.01)), food and inhalant allergic sensitization (1.72 (1.25, 2.36) to 12.64 (7.20, 22.18)), and physician-diagnosed inhalant allergy (1.92 (1.34, 2.74) to 11.91 (7.52, 18.86)). Strongest effect estimates were observed of early and persistent eczema with the risk of physician-diagnosed food allergy (OR 6.95 (3.76, 12.84) and 35.05 (18.33, 70.00), respectively) and combined asthma and physician-diagnosed allergy (7.11 (4.33, 11.67) and 29.03 (15.27, 55.22), respectively). Eczema phenotypes were not associated with lung function measures.

Conclusion

Eczema phenotypes were differentially associated with risks of respiratory and allergic conditions in school-aged children. Children with early transient and persistent eczema might benefit from more intense follow-up for early identification and treatment of asthma and allergies.

Epidemiology and Burden of Food Allergy

PURPOSE OF REVIEW

In recent decades, food allergy has become an increasing concern for families, clinicians, and policymakers. This review aims to summarize what is currently known about the epidemiology and population-level burden of IgE-mediated food allergy, including its effects on quality of life.

RECENT FINDINGS

Prevalence surveys, healthcare utilization data, and findings from longitudinal cohort studies across the globe indicate that food allergy imposes a growing societal burden. Worryingly, recent data indicate that food allergies may be more prevalent among adult populations than previously acknowledged, with many reported cases of adult-onset allergies. While it remains unclear how much of the current population-level burden of disease results from true, IgE-mediated allergy, as much epidemiological data does not incorporate clinical confirmation of disease prevalence-it is clear that affected individuals suffer impairments in their quality of life and incur substantial economic costs-beyond the physical health burden imposed by anaphylaxis.

Are the most common food allergens in an Iranian atopic population compatible with worldwide reports? A systemic review and meta-analysis with molecular classification of frequent allergens

BACKGROUND

Undesirable immunological responses to alimentary allergens are one of the hallmarks of atopic diseases. The prevalence of common food allergens is dissimilar among different communities with distinct nutritional habits and genetic characteristics.

AIM

To assess the prevalence of the most common food allergens in Iran, using different reliable studies.

METHODS

All studies determining sensitization to common food allergens that were indexed in PubMed, Web of Science, Google Scholar, ProQuest, Scopus, Iran Medex, and Magiran were included in this review. To perform a meta-analysis, STATA 14 and metaprop command was applied. A logistic-normal random-effects model with Freeman-Tukey double arcsin transformation was applied to combine the findings of different studies and evaluate their heterogeneity. Random pooled estimate (ES) (pooled prevalence), 95% confidence interval (95% CI) and p-value were determined.

RESULTS

A total of 23 studies with data from a total of 6126 children and adults met the inclusion criteria for entering this meta-analysis. The respective pooled prevalence of a positive family history of allergy and positive specific IgE to at least one food allergen was 72% (95% CI: 66-77%) and 41% (95% CI: 33-49%), respectively. Our results in the total population revealed that allergic sensitization to egg yolk, cow's milk (CM), egg white, and wheat were 25% (95% CI: 16%-35%), 24% (95% CI: 19-29%), 23% (95% CI: 18%-28%), and 9% (95% CI: 6%-14%), respectively. Walnut, peanut, and soybean sensitization was detected in 23% (95% CI: 17%-31%), 23% (95% CI: 13%-33%), and 20% (95% CI: 12%-28%) of patients, respectively. Random pooled ES for sensitization to shrimp and fish was 32% (95% CI: 21-45%) and 12% (95% CI: 6-20%), respectively. The result of analysis in different age groups revealed that allergic sensitization to milk, egg white, and egg yolk declines in higher age groups; while shrimp sensitization increases in older patients. In patients with atopic dermatitis, egg white was the most frequent food allergen 29% (95% CI = 18-42%); while wheat was the least frequent 8% (95% CI = 4-14%).

CONCLUSIONS

Considering the prevalence of different food allergens, the results of the current meta-analysis revealed that egg yolk and cow's milk had the second and third rate after shrimp, respectively. The high prevalence of sensitization to shrimp may be attributed to its high consumption in coastal areas and/or cross-reactivity of shrimp with some aeroallergens such as mites.

High-Dose Vitamin D Supplementation Does Not Prevent Allergic Sensitization of Infants

OBJECTIVE

To investigate the effect of vitamin D supplementation dose on allergic sensitization and allergic diseases in infants, and to evaluate whether vitamin D status in pregnancy and at birth are associated with infant allergy outcomes.

STUDY DESIGN

Altogether, 975 infants participated in a randomized, controlled trial of daily vitamin D supplementation of 10 μg (400 IU) or 30 μg (1200 IU) from the age of 2 weeks. At 12 months of age, food and aeroallergen IgE antibodies were measured, and the occurrence of allergic diseases and wheezing were evaluated.

RESULTS

We found no differences between the vitamin D supplementation groups in food (OR, 0.98; 95% CI, 0.66-1.46) or aeroallergen sensitization at 12 months (OR, 0.76; 95% CI,0.34-1.71). Allergic diseases or wheezing did not differ between groups, except for milk allergy which occurred more often in infants administered 30 μg vitamin D compared with the 10 μg dose (OR, 2.23; 95% CI, 1.00-4.96). Infants with high cord blood 25-hydroxyvitamin D (≥100 nmol/L) had a higher risk of food allergen sensitization compared with those with lower 25(OH)D concentration (75-99.9 nmol/L; OR, 2.00; 95% CI, 1.19-3.39).

CONCLUSIONS

High-dose vitamin D supplementation did not prevent allergic sensitization, allergic diseases, or wheezing during the first year of life. In contrast, we observed an increased risk of milk allergy in infants randomized to higher vitamin D supplementation, and an increased risk of allergic sensitization in infants with high cord blood vitamin D status, indicating a possible adverse effect of high concentrations of vitamin D.