ICON: food allergy

Quality Appraisal of Quality of Life Research in Children and Adolescents with Food Allergy: A Systematic Review

INTRODUCTION

Quality of life (QOL) and health-related quality of life (HRQOL) in children and adolescents with food allergies have been an important and steadily growing field of research for the past 20 years. There seem to be conceptual and methodological challenges that might influence the face validity of QOL and HRQOL research in general health research, but this has not been investigated in pediatric and adolescent food allergy research up until now. The aim of this study was to perform a systematic review of the QOL and HRQOL studies on food allergy in children and adolescents under the age of 18.

METHODS

The systematic review was conducted on studies purporting to measure QOL or HRQOL in children and adolescents with food allergies. The literature search was developed in Ovid MEDLINE and databases used in the review were Embase, Cochrane Database of Systematic Reviews, CINAHL, and Scopus. Studies were evaluated based on a set of face validity criteria developed by Gill and Feinstein in 1994 and refined by Moons et al. in 2004.

RESULTS

Out of 61 studies eligible for the review, 11 (18%) defined QOL or HRQOL and two distinguished QOL from HRQOL. The Food Allergy Quality of Life (FAQLQ) instrument series is the most frequently used HRQOL measurement among the studies included. QOL and HRQOL were employed interchangeably in half of the studies, some of them also using a third term in addition.

CONCLUSION

Our findings lead to the conclusion that the research field investigated contains methodological and conceptual shortcomings regarding QOL and HRQOL. An increased awareness toward the terminology as well as consideration of points to reflect upon will be beneficial, as this will also improve the validity of future studies.

Risk Factors for Acute Asthma Exacerbations in Adults With Mild Asthma

BACKGROUND

Although individuals with mild asthma account for 30% to 40% of acute asthma exacerbations (AAEs), relatively little attention has been paid to risk factors for AAEs in this population.

OBJECTIVE

To identify risk factors associated with AAEs in patients with mild asthma.

METHODS

This was a retrospective cohort study. We used administrative data from a large managed care organization to identify 199,010 adults aged 18 to 85 years who met study criteria for mild asthma between 2013 and 2018. An asthma-coded qualifying visit (index visit) was identified for each patient. We then used information at the index visit or from the year before the index visit to measure potential risk factors for AAEs in the subsequent year. An AAE was defined as either an asthma-coded hospitalization or emergency department visit, or an asthma-related systemic corticosteroid administration (intramuscular or intravenous) or oral corticosteroid dispensing. Poisson regression models with robust SEs were used to estimate the adjusted risk ratios for future AAEs.

RESULTS

In the study cohort, mean age was 44 years and 64% were female; 6.5% had AAEs within 1 year after the index visit. In multivariate models, age, sex, race, ethnicity, smoking status, body mass index, prior acute asthma care, and a variety of comorbidities and other clinical characteristics were significant predictors for future AAE risk.

CONCLUSION

Population-based disease management strategies for asthma should be expanded to include people with mild asthma in addition to those with moderate to severe disease.

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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

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

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

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

New Approaches to Food Allergy Immunotherapy

Food allergy is an increasing public health problem in children and adults. In addition to the risk of potentially severe reactions, food allergy can have a significant burden on quality of life, nutrition, cost of living, and social activities. Traditionally, treatment has primarily included strict food allergen avoidance and use of emergency medications to treat an allergic reaction. However, in recent years, there have been significant strides in the advancement of food allergy treatment, including the approval of the first and only approved therapy (peanut oral immunotherapy) for food allergy in 2020. Clinical trials have primarily focused on food allergen immunotherapy (oral, epicutaneous, sublingual). Building off of a foundation of promising data supporting the efficacy of food oral immunotherapy and our greater understanding of the underlying mechanism of immunotherapy, newer approaches, including alternative routes of delivery, adjuncts to therapy, modified allergens, and utilization in younger patients, aim to provide safer and more effective treatment approaches to the millions of patients burdened by food allergy.

A comprehensive review on mango allergy: Clinical relevance, causative allergens, cross-reactivity, influence of processing techniques, and management strategies

Mangoes (Mangifera indica) are widely prized for their abundant nutritional content and variety of beneficial bioactive compounds and are popularly utilized in various foods, pharmaceuticals, and cosmetics industries. However, it is important to note that certain proteins present in mango can trigger various allergic reactions, ranging from mild oral allergy syndrome to severe life-threatening anaphylaxis. The immunoglobulin E-mediated hypersensitivity of mango is mainly associated with three major allergenic proteins: Man i 1 (class IV chitinase), Man i 2 (pathogenesis-related-10 protein; Bet v 1-related protein), and Man i 4 (profilin). Food processing techniques can significantly affect the structure of mango allergens, reducing their potential to cause allergies. However, it is worth mentioning that complete elimination of mango allergen immunoreactivity has not been achieved. The protection of individuals sensitized to mango should be carefully managed through an avoidance diet, immediate medical care, and long-term oral immunotherapy. This review covers various aspects related to mango allergy, including prevalence, pathogenesis, symptoms, and diagnosis. Furthermore, the characterization of mango allergens and their potential cross-reactivity with other fruits, vegetables, plant pollen, and seeds were discussed. The review also highlights the effects of food processing on mango and emphasizes the available strategies for managing mango allergy.

Diet Diversity During Infancy and the Prevalence of Sensitization and Allergy in Children up to 3 Years of Age in the Kujawsko-Pomorskie Voivodeship, Poland

The study examines the influence of a diversified diet, changes in the consistency of introduced foods, and the method of meal preparation during infancy on the development of sensitization and/or allergy in toddlers. Introducing more product groups into the diet reduced the risk of allergy at 6 months of age (adjusted odds ratio [aOR] = 0.17; 95% confidence interval [CI] 0.04-0.71; P = 0.015) and at 12 months (aOR = 0.14; 95% CI 0.03-0.57; P = 0.006). Children with allergy and/or sensitization had been introduced to fewer product groups at 6 months (P = 0.003; P < 0.001; P = 0.008) and at 12 months (P = 0.001, P < 0.001; P = 0.001) compared with those without allergy and/or sensitization. Children with allergy and/or sensitization were fed ready-made, ie, purchased, products significantly more often than self-prepared foods compared with children without allergy and/or sensitization (P = 0.001; P = 0.006). Allergic and/or sensitized children tended to be switched to solids later (11 vs 10 months, P = 0.041; P = 0.037) (12 vs 10 months, P = 0.013) than children without sensitization and/or allergy. The earlier introduction of a varied diet reduced the risk of allergy and/or sensitization. Delaying the introduction of solid foods and using ready-made products instead of self-prepared ones increases the risk of allergy in toddlers.

Clinically and industrially relevant incurred reference materials to improve analysis of food allergens, milk, egg, almond, hazelnut and walnut

Measurement of food allergen protein concentrations against thresholds can improve allergen risk management and precautionary allergen labelling. Such measurement suffers well known problems which could be ameliorated by well characterised reference materials (RMs) providing meaningful information for risk assessors. We investigated the preparation and characterisation of the first consensus informed industrially and clinically relevant multi-allergen matrix RM kit for five priority allergens. It is a medium analytical difficulty processed food chocolate paste matrix (a) devoid of allergens, and (b) incurred with five allergens at the clinically relevant concentration of 10 mg kg-1 expressed as protein. The allergen raw materials: hens' egg white powder, skimmed cows' milk powder, almond powder (full fat), hazelnut powder (partially defatted), and walnut powder (partially defatted), are also available as RMs. The preparation, gravimetric traceability to the SI, homogeneity, and stability were found to be fit-for-purpose and the RMs are now available to the analytical community.

Preparation of poly(caffeic acid)-coated epitope molecularly imprinted polymers and investigation of adsorption performance toward ovalbumin

Food allergy can lead to severe allergic reactions that are potentially fatal for human, hence the detection of food allergens such as ovalbumin (OVA) is important. In this study, a poly(caffeic acid)-coated epitope molecularly imprinted polymer (EMIP) was prepared by chelation and autoxidation of caffeic acid with hexamethylenediamine. EMIP has not only imprinted cavities highly matched with OVA in size and spatial structure, but also externally abundant hydrophilic groups, resulting in few non-specific binding and good hydrophilicity. With high specificity, significant paramagnetism, and great reusability, EMIP can distinguish OVA from other proteins and selectively enrich OVA in egg white samples, which opens up a promising route to the determination of allergens in food products.

An ESPGHAN Position Paper on the Diagnosis, Management, and Prevention of Cow's Milk Allergy

A previous guideline on cow's milk allergy (CMA) developed by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) was published in 2012. This position paper provides an update on the diagnosis, treatment, and prevention of CMA with focus on gastrointestinal manifestations. All systematic reviews and meta-analyses regarding prevalence, pathophysiology, symptoms, and diagnosis of CMA published after the previous ESPGHAN document were considered. Medline was searched from inception until May 2022 for topics that were not covered in the previous document. After reaching consensus on the manuscript, statements were formulated and voted on each of them with a score between 0 and 9. A score of ≥6 was arbitrarily considered as agreement. Available evidence on the role of dietary practice in the prevention, diagnosis, and management of CMA was updated and recommendations formulated. CMA in exclusively breastfed infants exists, but is uncommon and suffers from over-diagnosis. CMA is also over-diagnosed in formula and mixed fed infants. Changes in stool characteristics, feeding aversion, or occasional spots of blood in stool are common and in general should not be considered as diagnostic of CMA, irrespective of preceding consumption of cow's milk. Over-diagnosis of CMA occurs much more frequently than under-diagnosis; both have potentially harmful consequences. Therefore, the necessity of a challenge test after a short diagnostic elimination diet of 2-4 weeks is recommended as the cornerstone of the diagnosis. This position paper contains sections on nutrition, growth, cost, and quality of life.

[Classification of food allergy: generalities]

The prevalence of food allergy has increased in some regions of the world, and with it the incidence, according to geographical variability, in the phenotype and clinical manifestations. Food allergy arises from the specific immune response induced by exposure to the proteins of a certain food. Food intolerance refers to non-immune reactions, caused by unique physiological characteristics of the individual, including metabolic, toxic, pharmacological and undefined mechanisms. Adverse reactions to foods are classified as: IgE-mediated: Type I Hypersensitivity, non-IgE-mediated: Type IV Hypersensitivity, mixed: Types I and IV Hypersensitivity Non-Allergic; toxic, pharmacological, metabolic, intolerances. These types of alterations are rare but have increased in recent years; These include protein-induced enterocolitis syndrome, which can cause emesis, diarrhea and hypotension, and shock, which begins two hours after ingestion of the allergen. Protein-induced allergic proctocolitis is a condition that includes allergy to cow's milk protein. Delayed reactions usually affect the digestive system, are more insidious in their onset and are not immediately controlled, even with the suspension of food. There are eight foods responsible for 90% of food allergies: milk, eggs, soy, wheat, peanuts, walnuts, fish, and shellfish.

[Differential diagnosis in food allergy]

It is important to establish the differential diagnosis of food allergy with other disorders, for example: toxic reactions that occur in any person exposed to a sufficient amount of some allergen, and non-toxic reactions that depend on individual susceptibility (food allergy or intolerance). The differential diagnosis is decisive to establish the appropriate treatment. Food intolerance involves adverse reactions to foods without any immunological response involved, and commonly manifests with gastrointestinal symptoms (malaise, abdominal pain or diarrhea). Food allergy is an exaggerated reaction of the immune system, often mediated by IgE, that can trigger serious symptoms (hives, inflammation, respiratory distress, even anaphylaxis). The complex thing is because the symptoms sometimes overlap. To establish an accurate diagnosis, exhaustive clinical evaluation, laboratory tests and, in some cases, controlled provocation tests are required. It is important to understand these distinctions, because treatment and management vary significantly. Food intolerance involves the elimination or reduction of the food that triggers the allergic reaction and requires rigorous measures (complete avoidance of the allergen and availability of epinephrine in cases of severe reactions).

[Introduction to food allergy]

Food allergy is a common chronic disorder that affects infants, children, adolescents, and adults. The prevalence of food allergy has increased in recent decades throughout the world, not limited to Western countries. Since there is no treatment, this focuses on avoiding allergens, in addition to educating patients and caregivers in the emergency treatment of acute reactions, for example: application of epinephrine. Studies suggest that accidental reactions occur in about 45% of children with food allergies each year, although most reactions are mild or moderate in severity. Hospital admissions for food anaphylaxis vary from 4 to 20 per 100,000 inhabitants; Deaths are rare, with an estimated incidence of 0.03 to 0.3 per million people with food allergy. Death from food anaphylaxis is rare and appears to have remained stable, possibly due to increases in food allergen labeling, diagnostic services, rates of intramuscular epinephrine prescription, and awareness of food allergies. Omalizumab is a drug approved for several disorders (chronic hives or difficult asthma) and may help reduce symptoms associated with food allergy. The relative importance of alternative technologies, management strategies and policies for food allergy varies from one region to another, due to differences in the epidemiology, education, socioeconomic well-being, and cultural preferences of the population.

[Non-IgE-mediated food allergy]

Food allergy is an immune response to proteins in food. It usually affects 8% of children and 2% of adults in Western countries. Non-IgE-mediated food allergy mainly affects the gastrointestinal tract. Gastrointestinal food allergies are classified, by their underlying pathogenesis, as: IgE-mediated, non-IgE-mediated, or mixed. The symptoms of patients with food protein-induced allergic proctocolitis originate from local inflammation of the distal colon, which causes hematochezia in neonates. It can affect the entire gastrointestinal tract and cause symptoms of intractable emesis, with subsequent metabolic disorders and hypovolemic shock. Food protein-induced enterocolitis syndrome is a non-IgE-mediated allergy that usually appears in childhood, with prolonged repetitive vomiting, starting 1 to 4 hours after ingestion of food. The manifestation in adults is usually triggered by the consumption of shellfish. Atopic diseases affect 40-60% of patients with food protein- induced enterocolitis syndrome, including 40-50% of those with food protein-induced enteropathy and proctocolitis. Probiotics (Lactobacillus GG) can alleviate the symptoms of allergic proctocolitis induced by food proteins, by altering the composition of the intestinal microbiota. Fecal microbiota transplantation (FMT) can change intestinal microecology efficiently compared to food or probiotics.

Prospects for developing allergen-depleted food crops

In addition to the challenge of meeting global demand for food production, there are increasing concerns about food safety and the need to protect consumer health from the negative effects of foodborne allergies. Certain bio-molecules (usually proteins) present in food can act as allergens that trigger unusual immunological reactions, with potentially life-threatening consequences. The relentless working lifestyles of the modern era often incorporate poor eating habits that include readymade prepackaged and processed foods, which contain additives such as peanuts, tree nuts, wheat, and soy-based products, rather than traditional home cooking. Of the predominant allergenic foods (soybean, wheat, fish, peanut, shellfish, tree nuts, eggs, and milk), peanuts (Arachis hypogaea) are the best characterized source of allergens, followed by tree nuts (Juglans regia, Prunus amygdalus, Corylus avellana, Carya illinoinensis, Anacardium occidentale, Pistacia vera, Bertholletia excels), wheat (Triticum aestivum), soybeans (Glycine max), and kidney beans (Phaseolus vulgaris). The prevalence of food allergies has risen significantly in recent years including chance of accidental exposure to such foods. In contrast, the standards of detection, diagnosis, and cure have not kept pace and unfortunately are often suboptimal. In this review, we mainly focus on the prevalence of allergies associated with peanut, tree nuts, wheat, soybean, and kidney bean, highlighting their physiological properties and functions as well as considering research directions for tailoring allergen gene expression. In particular, we discuss how recent advances in molecular breeding, genetic engineering, and genome editing can be used to develop potential low allergen food crops that protect consumer health.

Oral immunotherapy in alpha-gal red meat allergy: Could specific IgE be a potential biomarker in monitoring management?

BACKGROUND

Oral immunotherapy (OIT) is a promising treatment for food allergies. Our aim was to establish the long-term safety and efficacy of a novel red meat (RM) OIT in galactose-alpha-1,3-galactose (alpha-gal) allergy in adults.

METHODS

Out of 20 patients with confirmed RM allergy, five (41.66%) underwent an early OIT, seven (58.33%) underwent a delayed protocol and eight patients who were not desensitized formed the patient control group. 15 and 27 day RM OIT for early-onset and delayed-onset alpha-gal allergy were administered, respectively. Desensitized patients were recommended to continue eating at least 100 g RM every day for 6 months and every other day in the following 6 months. After a year, the consumption was recommended 2/3 times in a week. Patients were followed up with skin tests with commercial beef and lamb extracts, fresh raw/cooked beef and lamb and cetuximab and also with serum alpha-gal specific Immunoglobulin-E (sIgE) in the first and fifth years.

RESULTS

All patients who underwent OIT became tolerant to RM. During the 5 year follow-up, the median alpha-gal sIgE concentration gradually decreased in nine patients who consumed RM uneventfully while remained unchanged in the control group (p = .016). In two patients, rare tick bites acted as inducers of hypersensitivity reactions with concomitant elevation of alpha-gal sIgE concentrations whereas one patient with low follow-up alpha-gal sIgE concentrations consumed RM uneventfully after frequent tick bites.

CONCLUSIONS

Our study showed the long-term safety and efficacy of alpha-gal OIT. Additionally, alpha-gal sIgE seems to be a potential biomarker to monitor OIT.

Brittle Asthma: Still on Board?

(1) Background: "Brittle Asthma" was considered an asthma clinical phenotype and deemed to be life-threatening in the early 2000s; then, this definition disappeared. The purpose of this review is to examine what has historically been referred to as this term and see whether it may be applied to modern clinical practice, thus acquiring fresh relevance and meaning. (2) Methods: A non-systematic search of the literature was conducted using both MeSH and free-text phrases. No limitations on the research design or type of publication were applied. (3) Results: Reliable data regarding "Brittle Asthma" are lacking due to the paucity of current data and the few studies available. After a few years of reworking, it was divided into two sub-classes: one characterized by a wide PEF variability despite high-dose therapy and the other by sudden acute attacks in otherwise apparently normal airway functions or well-controlled asthma. Their characteristics were hardly defined because of their low prevalence. Data regarding risk factors, atopy, mechanisms, and treatments were analyzed. (4) Conclusions: Over time, different terminology has been introduced to define asthma severity and control. It would be worth investigating whether the term "Brittle Asthma" previously used may be helpful to find new hints to stratify patients and improve disease management.

A mouse model of food allergy permitting skin and nasal symptoms

PURPOSE

Developing experimental animal models that show clinical symptoms and methods for quantitative and objective evaluation are important for understanding food allergies. Therefore, this study aimed to develop an ovalbumin (OVA)-induced mouse model of food allergy and a useful method to evaluate the symptoms of food allergy.

MATERIAL/METHODS

Mice were sensitized via intraperitoneal injection of OVA. Subsequently, local sensitization was performed once weekly by oral administration of OVA. Itching and nasal symptoms were observed after oral administration of the antigen. First, we examined the dose-dependency of the antigen. Symptoms were checked weekly. In order to confirm food allergy symptoms, the effect of histamine H1 receptor antagonist was examined. Finally, we measured antigen-specific IgE antibody levels in the serum.

RESULTS

Scratching behavior, sneezing and nasal rubbing were increased. Both itching and rhinitis symptoms increased steadily, after which, the number of symptoms remained almost constant. No difference was observed between the results of 3- and 5-week-old mice. Cetirizine inhibited these symptoms in a dose-dependent manner. In addition, antigen-specific IgE antibodies were produced in both 3- and 5-week-old mice.

CONCLUSIONS

This method may be useful for evaluating the symptoms of skin and rhinitis that could not be assessed in the conventional food allergy model and could be induced with a low dose of antigen. In particular, the developed method, which measures the number of itching and nasal symptoms, may enable quantitative, objective, and noninvasive evaluation of food allergy severity.

Inter-embodied parental vigilance; the case of child food allergy

There is developing interest in issues of embodiment in studies of children, health and illness. We take our point of departure in the parent-child-health/illness triad to explore the embodied aspects of parental vigilance in parenting children who have a food allergy, utilizing the concept of inter-embodiment. Drawing on a focus group study with parents in Sweden the analysis reveals that this vigilance can be seen as the embodied manifestation of concern for children's bodies in perpetual liminality, when constantly exposed to allergens and the risk of becoming ill. We argue that the lens of inter-embodiment, with a focus on bodies in relation, captures how parents lived experience of managing food allergy intertwines with that of their children in the parent-child-health/illness triad. The analysis uncovers a form of embodied knowledge that is often not verbalized, offering potential for new understandings of parent-child relations that center on chronic child health conditions.

Iron/iron oxide-based magneto-electrochemical sensors/biosensors for ensuring food safety: recent progress and challenges in environmental protection

Foodborne diseases have arisen due to the globalization of industry and the increase in urban population, which has led to increased demand for food and has ultimately endangered the quality of food. Foodborne diseases have caused some of the most common public health problems and led to significant social and economic issues worldwide. Food quality and safety are affected by microbial contaminants, growth-promoting feed additives (β-agonists and antibiotics), food allergens, and toxins in different stages from harvesting to storage and marketing of products. Electrochemical biosensors, due to their reduced size and portability, low cost, and low consumption of reagents and samples, can quickly provide valuable quantitative and qualitative information about food contamination. In this regard, using nanomaterials can increase the sensitivity of the assessment. Magnetic nanoparticle (MNP)-based biosensors, especially, are receiving significant attention due to their low-cost production, physicochemical stability, biocompatibility, and eco-friendly catalytic characteristics, along with magnetic, biological, chemical and electronic sensing features. Here, we provide a review on the application of iron-based magnetic nanoparticles in the electrochemical sensing of food contamination. The types of nanomaterials used in order to improve the methods and increase the sensitivity of the methods have been discussed. Then, we stated the advantages and limitations of each method and tried to state the research gaps for each platform/method. Finally, the role of microfluidic and smartphone-based methods in the rapid detection of food contamination is stated. Then, various techniques like label-free and labelled regimes for the sensitive monitoring of food contamination were surveyed. Next, the critical role of antibody, aptamer, peptide, enzyme, DNA, cells and so on for the construction of specific bioreceptors for individual and simultaneous recognition by electrochemical methods for food contamination were discussed. Finally, integration of novel technologies such as microfluidic and smartphones for the identification of food contaminations were investigated. It is important to point out that, in the last part of each sub-section, attained results of different reports for each strategy were compared and advantages/limitations were mentioned.

An unexpected allergic skin reaction to peppermint oil capsules

Peppermint oil capsules are prescribed to manage abdominal colic and distension, a common complaint in postcaesarean section patients. Arachis (peanut) oil is contained within one frequently prescribed peppermint formulation: Colpermin. This ingredient is contraindicated in patients with peanut and soya allergy; however, this is not stated in the side effects or contraindications section of the British National Formulary, or present on the medication packaging. A postpartum woman in her early 30s had an unexpected allergic reaction to the capsules, in the form of a generalised body rash, fortunately with no anaphylactic features. The patient reported the same reaction to soya in the past. After review of the patient's clinical and medication history, Colpermin capsules were thought to be responsible for the patient's symptoms. This case highlights the necessity for clearer documentation in prescribing formularies and on medication packaging to ensure patient safety.

Vitamin D and Omega-3 (Fatty Acid) Supplementation in Pregnancy for the Primary Prevention of Food Allergy in Children-Literature Review

During the last decades the prevalence of food allergy (FA), an adverse immune response to a specific food antigen, has risen, with negative effects on the quality of life (QoL) of many children and their families. The pathogenesis of FA is complex, involving both genetic and environmental factors. SPINK5, STAT6, HLA and FOXP3 are some of the genes that are reported to be implicated in FA development. Regarding environmental factors, particular interest has been focused on modification of the dietary habits of pregnant women for the primary prevention of FA. Specifically, Vitamin D and omega-3 (Ω-3) fatty acid supplementation during pregnancy may influence the development of FA in the offspring. Vitamin D is a hormone with various actions, including mediation of the immune system, reducing the production of inflammatory cytokines and promoting tolerance. Vitamin D deficiency in pregnancy suppresses T-regulatory cells in the fetus, and Vitamin D supplementation might protect against FA development. Dietary Ω-3 fatty acids are found mainly in fish and vegetable oils. They are beneficial for human health, playing a role in the immune system as anti-inflammatory agents, and providing cell membrane stabilization with inhibition of antigen presentation. It is documented that maternal supplementation with Ω-3 during pregnancy may protect from allergic sensitization in the children. The aim of this literature review was to explore the potential preventive role of maternal supplementation during pregnancy with Vitamin D and Ω-3 in the development of FA in the offspring. With the prevalence of FA rising, all the possible protective mechanisms and measures for FA prevention need to be explored, starting with those that can be modified.

Gut Microbiome Proteomics in Food Allergies

Food allergies (FA) have dramatically increased in recent years, particularly in developed countries. It is currently well-established that food tolerance requires the strict maintenance of a specific microbial consortium in the gastrointestinal (GI) tract microbiome as alterations in the gut microbiota can lead to dysbiosis, causing inflammation and pathogenic intestinal conditions that result in the development of FA. Although there is currently not enough knowledge to fully understand how the interactions between gut microbiota, host responses and the environment cause food allergies, recent advances in '-omics' technologies (i.e., proteomics, genomics, metabolomics) and in approaches involving systems biology suggest future headways that would finally allow the scientific understanding of the relationship between gut microbiome and FA. This review summarizes the current knowledge in the field of FA and insights into the future advances that will be achieved by applying proteomic techniques to study the GI tract microbiome in the field of FA and their medical treatment. Metaproteomics, a proteomics experimental approach of great interest in the study of GI tract microbiota, aims to analyze and identify all the proteins in complex environmental microbial communities; with shotgun proteomics, which uses liquid chromatography (LC) for separation and tandem mass spectrometry (MS/MS) for analysis, as it is the most promising technique in this field.

New Indications of Biological Drugs in Allergic and Immunological Disorders: Beyond Asthma, Urticaria, and Atopic Dermatitis

Asthma, chronic urticaria, and atopic dermatitis are some of the most numerous allergic diseases affecting children. Recent advances in the understanding of their specific intracellular molecular pathways have led to the approval of monoclonal antibodies targeting definite inflammatory molecules in order to control symptoms and improve quality of life. Less is known about other allergic and immunologic disorders such as rhinosinusitis with nasal polyps, eosinophilic esophagitis, anaphylaxis, and food allergy undergoing allergen immunotherapy. The increasing evidence of the molecular mechanisms underlying their pathogeneses made it possible to find in children new indications for known biological drugs, such as omalizumab and dupilumab, and to develop other ones even more specific. Promising results were recently obtained, although few are currently approved in the pediatric population. In this review, we aim to provide the latest evidence about the role, safety, and efficacy of biologic agents to treat allergic and immunologic diseases in children.

Risk assessment of azo dyes as food additives: Revision and discussion of data gaps toward their improvement

The food industry uses dyes mainly to overcome color loss during the processing and storage of products, with the azo dyes currently being the most employed. Studies on the safety of using these dyes in foods started in the 1950s and have indicated the potential for concern. This review discusses the risk assessment of food intake containing artificial azo dyes. There are case reports and, subsequently, double-blind placebo-controlled trials in some individuals who may experience adverse effects from the intake of azo dyes, but it is unclear whether these adverse effects are restricted to specific populations or more generalized. In view of this, different toxicological endpoints are evaluated to verify toxic effects in in vitro and in vivo models and to establish the no observed adverse effect level. Exposure estimation studies have shown that human exposure to azo dyes via oral intake is mainly below the acceptable daily intake established by advisory bodies. However, most countries do not have studies that estimate the oral intake of azo dyes. In this case, local food diversity and racial-ethnic specificities are not considered when stating the exposure estimate is below the acceptable daily intake for the human population and thus may not represent actual intake. Concerning the scenario established above, this review discusses the most critical gaps to be overcome to contribute to the direction of future studies and the development of more effective public policies concerning the safety of the intake of artificial azo dyes.

IgE and IgG4 Epitope Mapping of Food Allergens with a Peptide Microarray Immunoassay

Peptide microarrays are a powerful tool to identify linear epitopes of food allergens in a high-throughput manner. The main advantages of the microarray-based immunoassay are as follows: the possibility to assay thousands of targets simultaneously, the requirement of a low volume of serum, the more robust statistical analysis, and the possibility to test simultaneously several immunoglobulin subclasses. Among them, the last one has a special interest in the field of food allergy, because the development of tolerance to food allergens has been associated with a decrease in IgE and an increase in IgG4 levels against linear epitopes. However, the main limitation to the clinical use of microarray is the automated analysis of the data. Recent studies mapping the linear epitopes of food allergens with peptide microarray immunoassays have identified peptide biomarkers that can be used for early diagnosis of food allergies and to predict their severity or the self-development of tolerance. Using this approach, we have worked on epitope mapping of the two most important food allergens in the Spanish population, cow's milk, and chicken eggs. The final aim of these studies is to define subsets of peptides that could be used as biomarkers to improve the diagnosis and prognosis of food allergies. This chapter describes the protocol to produce microarrays using a library of overlapping peptides corresponding to the primary sequences of food allergens and data acquisition and analysis of IgE and IgG4 binding epitopes.

Detection of the peripheral blood antigens and clinical value in recurrent aphthous ulcer: A cross-section study

Abstract Background/purpose

Recurrent aphthous ulcer (RAU) is one of the most common diseases of oral mucosa, which is generally believed to be related to immunity, though the etiology is still unclear. It is suspected that allergies are directly related to RAU. So we sought to explore the relationship between hypersensitivity and RAU.

Materials and methods

40 RAU patients who were in ulceration period and 40 people who were in good health were selected from Jan 2016 to Feb 2017, matched in age and sex. The peripheral blood antigens of 40 RAU patients and 40 healthy people was tested, and serum specific IgE (sIgE) with 6 groups of antigens and total IgE (tIgE) analysis was performed to identify IgE-mediated allergic reaction possibly affecting RAU. We then investigated the food intolerance and IgG levels to discover the correlation between non-IgE mediated allergic reaction and RAU.

Results

The positive cases and rate of sIgE in RAU group was higher than that of control, but the difference was not statistically significant (P＞0.05). Positive grade of animal fur scraps (EX1), house dust mixed (HX2) and the serum tIgE concentration of the RAU group were significantly higher than the control group (P＜0.05).The number of food intolerance in RAU group was significantly higher than that in control group (P＜0.05).

Conclusion

Our findings suggested certain correlation between RAU and anaphylaxis. Daily contact allergens and food intolerance may be one of the causes of RAU. Moreover, this provides reference value for clinical diagnosis and treatment.

Approaches to Management of Asthma: Guidelines for Stepped Care and Self-Monitoring

While the twentieth century brought rapid changes to the diagnosis and management of asthma, consensus guidelines did not exist until the mid-1980s. Over the subsequent four decades, guidelines evolved from expert-based recommendations to comprehensive, evidenced-based references. The main two guidelines to be discussed in this chapter are the expert panel reports (EPR) published by the United States National Heart, Lung, and Blood Institute (NHLBI) and the Global Strategy for Asthma Management and Prevention Report (GINA) published by the NHLBI and World Health Organization (WHO). While these guidelines both focus on evidence-based approaches to the diagnosis and management of asthma, there are significant differences in both organization and recommendations. Just as the introduction of evidence-based guidelines was revolutionary to asthma management over the last 20 years, we anticipate further development of recommendations specific to precision medicine based on ongoing cutting-edge clinical research.

Alterations of the gut microbiota and short chain fatty acids in necrotizing enterocolitis and food protein-induced allergic protocolitis infants: A prospective cohort study

Background

Even though presenting with similar clinical manifestations, necrotizing enterocolitis (NEC) and food protein-induced allergic protocolitis (FPIAP) have completely different treatments and prognosis. Our study aimed to quantify and evaluate differences in gut microbiota and short chain fatty acids (SCFAs) between infants with NEC and FPIAP to better identify these two diseases in clinical settings.

Methods

A total of 43 infants with NEC or FPIAP in Children's Hospital of Chongqing Medical University, China between December 2020 and December 2021 were enrolled. Stool samples were prospectively collected and froze. Infants defined as NEC were those who presented with clinical courses consistent with NEC and whose radiographs fulfilled criteria for Bell's stage 2 or 3 NEC, while those who were healthy in appearance and had blood in the stool (visible or may be microscopic), had normal bowel sounds in physical examination, were resolved after eliminating the causative food, and/or had recurrence of symptoms after oral food challenge (OFC) were defined as FPIAP. Primers specific for bacterial 16S rRNA genes were used to amplify and pyrosequence fecal DNA from stool samples. Gas chromatography-mass spectrometry (GC-MS) technology was used to determine the concentrations of SCFAs.

Results

Among the 43 infants, 22 were diagnosed with NEC and 21 were diagnosed with FPIAP. The microbial community structure in NEC infant stools differed significantly from those in FPIAP infant stools. NEC infants had significantly higher proportion of Actinobacteria and reduced proportion of Bacteroidetes compared with FPIAP infants, and the proportions of Halomonas, Acinetobacter, Bifidobacterium, and Stenotrophomonas in NEC infants were significantly higher than that of FPIAP infants. In addition, infants with NEC had significantly lower levels of acetic acid, propionic acid, butyric acid, isovaleric acid, and total SCFAs, and higher level of hexanoic acid as compared to the infants of the FPIAP group.

Conclusions

The differences of gut microbiota composition and concentrations of SCFAs might represent suitable biomarker targets for early identification of NEC and FPIAP.

Detection of Fish Allergens in Foods Using an In-House Real-Time PCR Targeting the Ribosomal 18S rRNA Gene

Fish is one of the major food allergens which, in sensitised individuals, can cause life-threatening allergic reactions, even when present in small amounts. To protect consumers' health, the correct labeling of foods is important. The objective of the present study was to validate an in-house real-time PCR method targeting the ribosomal 18S rRNA gene as universal DNA marker for the detection of fish in foods. The specificity of the primers was assessed on 20 fish species commonly marketed in the Mediterranean basin and other species of molluscs and crustaceans and foods of animal and plant origin. The absolute detection of the method was assessed using DNA extracted from a fish mixture and the SureFood^® QUANTARD Allergen 40 reference material. The relative amount was assessed on a fish and béchamel sauce blend. Commercial food samples either labelled with or without fish in the ingredient list, were tested for the presence of fish DNA. The primer showed high specificity against the selected fish species. The limit of detection (LOD) and limit of quantification (LOQ) of the in-house method were 0.5 pg/µL and 5 pg/µL, respectively. The relative quantification in fish and béchamel blend samples detected a concentration as low as 0.000025%, corresponding to 0.25 mg/kg of fish, indicating the suitability of the method in a food matrix. The presence of fish DNA was always detected in commercial samples in which the presence of fish was listed in the ingredient list. The method was able to detect the presence of fish DNA also in samples in which the presence of fish was indicated as traces or was not declared on the label. The proposed method was demonstrated to be a reliable, specific, and sensitive method for the detection of fish allergens in foods. Therefore, the proposed real-time PCR method could be used as a useful instrument in the verification of compliance with allergen labelling regulations.

Treating allergies via skin - Recent advances in cutaneous allergen immunotherapy

Subcutaneous allergen immunotherapy has been practiced clinically for decades to treat airborne allergies. Recently, the cutaneous route, which exploits the immunocompetence of the skin has received attention, which is evident from attempts to use it to treat peanut allergy. Delivery of allergens into the skin is inherently impeded by the barrier imposed by stratum corneum, the top layer of the skin. While the stratum corneum barrier must be overcome for efficient allergen delivery, excessive disruption of this layer can predispose to development of allergic inflammation. Thus, the most desirable allergen delivery approach must provide a balance between the level of skin disruption and the amount of allergen delivered. Such an approach should aim to achieve high allergen delivery efficiency across various skin types independent of age and ethnicity, and optimize variables such as safety profile, allergen dosage, treatment frequency, application time and patient compliance. The ability to precisely quantify the amount of allergen being delivered into the skin is crucial since it can allow for allergen dose optimization and can promote consistency and reproducibility in treatment response. In this work we review prominent cutaneous delivery approaches, and offer a perspective on further improvisation in cutaneous allergen-specific immunotherapy.

Long-term IgE immunological tolerance to peanut allergens: An alternative to Noon's daily desensitization paradigm

Herein, we show that profound afferent long-term peanut-allergen-specific IgE immunological tolerance for 3 to 9 months induced sustained unresponsiveness (SU) in naïve or peanut-sensitized rodents after peanut allergen immunization. Rodents were vaccinated sublingually with a peanut allergen extract or recombinant peanut allergen in chenodeoxycholate (CDCA), a fanesoid X receptor (FXR, NR1H4) agonist that downregulates SREBP-1c (sterol regulatory element binding protein-1c) and upregulates SHP in bone marrow-derived tolerogenic dendritic cells (DCs). Approximately 90 ∼ 95 % of the total circulating PE-potentiated IgE and Ara h1, Ara h 2, and Ara h 6 peanut allergen-specific IgE responses were suppressed by recombinant peanut allergen-conjugated solid magnetic beads (sensitivity of 0.2 IU/ml). In contrast, peanut allergen-specific IgG production was not affected. Similarly, oleoylethanolamine (OEA), a peroxisome proliferator-activator receptor alpha (PPARα) agonist, and GW9662, a PPARγ antagonist, induced long-term peanut-specific IgE tolerance when administered via the sublingual, oral or i.p. route. Prophylactic Ara h2 DNA immunization with caNRF2 and IL-35 coexpression induced Ara h2 IgE tolerance. In summary, peanut allergen vaccination with select natural molecular ligands of nuclear receptors induced long-term peanut allergen-specific IgE tolerance via the afferent limb, which indicates that vaccination is an immune tolerance-promoting strategy that is effective at the DC level and that differs from Noon's daily desensitization program, which is effective at the mast cell level.

Comprehensive Analysis of the Structure and Allergenicity Changes of Seafood Allergens Induced by Non-Thermal Processing: A Review

Seafood allergy, mainly induced by fish, shrimp, crab, and shellfish, is a food safety problem worldwide. The non-thermal processing technology provides a new method in reducing seafood allergenicity. Based on the structural and antigenic properties of allergenic proteins, this review introduces current methods for a comprehensive analysis of the allergenicity changes of seafood allergens induced by non-thermal processing. The IgE-binding capacities/immunoreactivity of seafood allergens are reduced by the loss of conformation during non-thermal processing. Concretely, the destruction of native structure includes degradation, aggregation, uncoiling, unfolding, folding, and exposure, leading to masking of the epitopes. Moreover, most studies rely on IgE-mediated assays to evaluate the allergenic potential of seafood protein. This is not convincing enough to assess the effect of novel food processing techniques. Thus, further studies must be conducted with functional assays, in vivo assays, animal trials, simulated digestion, and intestinal microflora to strengthen the evidence. It also enables us to better identify the effects of non-thermal processing treatment, which would help further analyze its mechanism.

Insights into Microbiome and Metabolic Signatures of Children Undergoing Peanut Oral Immunotherapy

Background: Peanut oral immunotherapy has emerged as a novel, active management approach for peanut-allergic sufferers, but limited data exist currently on the role of the microbiome in successful desensitization. Objective: We examined the oral and gut microbiome in a cohort of 17 children undergoing peanut oral immunotherapy with the aim to identify the microbiome signatures associated with successful desensitization. We also set out to characterize their fecal metabolic profiles after successful therapy. Methods: Participants gradually built up their daily dose from 2 mg (starting dose) to 300 mg (maintenance dose) within approximately 40 weeks. We collected a buccal and stool specimen from each subject at two different time points: at baseline and post-therapy (1 month after reaching maintenance). The oral (buccal) and gut (fecal) microbiome was characterized based on sequencing of 16S rRNA gene amplicons with Illumina MiSeq. Fecal short chain fatty acid levels were measured using liquid chromatography-tandem mass spectrometry. Results: We report increased alpha diversity of the oral microbiome post-therapy and have also identified a significant increase in the relative abundance of oral Actinobacteria, associated with the desensitized state. However, the baseline gut microbiome did not differ from the post-therapy. Additionally, fecal short chain fatty acids increased after therapy, but not significantly. Conclusion: Our research adds to the limited current knowledge on microbiome and metabolic signatures in pediatric patients completing oral immunotherapy. Post-therapy increased trends of fecal fatty acid levels support a role in modulating the allergic response and potentially exerting protective and anti-inflammatory effects alongside successful desensitization. A better understanding of the microbiome-related mechanisms underlying desensitization may allow development of smarter therapeutic approaches in the near future. Clinical implication: The oral microbiome composition is altered following successful peanut oral immunotherapy, with a significant increase in alpha diversity and the relative abundance of phylum Actinobacteria. Capsule summary: Significant microbiome changes in children completing peanut immunotherapy include increase in alpha-diversity and overrepresentation of Actinobacteria in the oral microbiome, and increased trends for fecal short chain fatty acids, suggesting a protective effect against the allergic response.

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

Background

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

Objective

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

Methods

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

Results

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

Conclusion

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

Associations between comorbidities and annual incidence plus frequency of asthma exacerbation hospitalisation during the past year: data from CARN study

Purpose

While asthma comorbidities are associated with higher health care utilisation, lower quality of life and poorer asthma control, the impact of asthma comorbidities on hospitalisation for asthma exacerbation (H-AX) remains less recognised. We aim to analyse the impact of asthma comorbidities on H-AX.

Methods

Based on a national survey on asthma control and disease perception (CARN 2015 study), we analysed the impact of comorbidities on annual incidence and frequency of H-AX in China. Information on demographic characteristics, asthma comorbidities and annual incidence and frequency of H-AX were presented in this study.

Results

Among 3875 ambulatory asthma patients, 75.9% (2941/3875) had comorbidities, and 26.4% (1017/3858) experienced H-AX during past year. After adjusting for confounding factors such as demographic data, smoking status and asthma control, COPD [OR = 2.189, 95% CI (1.673, 2.863)] and coronary heart disease [OR = 1.387, 95% CI (1.032, 1.864)] were associated with higher annual incidence, while allergic rhinitis [OR = 0.692, 95% CI (0.588, 0.815)] was associated with lower annual incidence, of H-AX. In terms of frequency, allergic rhinitis [OR = 1.630, 95% CI (1.214, 2.187)], COPD [OR = 1.472, 95% CI (1.021, 2.122)] and anxiety [OR = 2.609, 95% CI (1.051, 6.477)] showed statistically significant correlation with frequent H-AX.

Conclusions

COPD and coronary heart disease were associated with higher annual incidence, while allergic rhinitis was associated with lower annual incidence of H-AX. Allergic rhinitis, COPD and anxiety were associated with frequent H-AX. Comorbidities may have an important role in the risk and frequency of annual hospitalisations due to asthma exacerbation. The goal of asthma control should rely on a multi-disciplinary treatment protocol.

Challenges in uncontrolled asthma in pediatrics: important considerations for the clinician

INTRODUCTION

Despite symptoms control being the primary focus of asthma management according to guidelines, uncontrolled asthma is still an issue worldwide, leading to huge costs and asthma deaths at all ages. In childhood, poor asthma control can be even more harmful, as it can irreversibly compromise the children's lung function and the whole family's well-being.

AREAS COVERED

Given the problem extent, this review aims to discuss the leading modifiable causes of uncontrolled asthma in Pediatrics, giving some practical insights regarding the critical role of families and the main tools for monitoring control and drug adherence, even at a distance. The most recent GINA documents were used as the primary reference, along with the latest evidence regarding the management of asthma control and the impact of the COVID-19 pandemic on asthma.

EXPERT OPINION

In managing pediatric asthma, a multidisciplinary, multi-determinant, personalized approach is needed, actively involving families, schools, and other specialists. In addition to current strategies for implementing control, electronic health strategies, new validated asthma control tools, and the identification of novel inflammatory biomarkers could lead to increasingly tailored therapies with greater effectiveness in reaching asthma control.

Clinical Features and Clinical Course of Food Protein-Induced Allergic Proctocolitis: 10-Year Experience of a Tertiary Medical Center

BACKGROUND

Food protein-induced allergic proctocolitis (FPIAP) is a food allergy characterized by bloody stools in well-appearing breast-fed infants.

OBJECTIVE

To determine the clinical course of FPIAP and the factors affecting the development of tolerance.

METHODS

Over a 10-year period, patients with a diagnosis of FPIAP who were followed at the outpatient Allergy-Immunology clinic in a tertiary care children's hospital in Turkey were retrospectively analyzed.

RESULTS

The frequency of FPIAP was 0.18% among 64,549 patients. The median age of symptom onset was 2 months (interquartile range, 1.0-3.5 months), and the median age of tolerance development was 12 months (interquartile range, 8.0-17.21 months). The occurrence of symptoms in the neonatal period was associated with a history of premature birth (odds ratio, 3.75; 95% CI, 1.33-10.59; P = .031) and neonatal intensive care unit hospitalization (odds ratio, 4.72; 95% CI, 1.78-12.53; P = .002). Use of a cow's milk-based formula was associated with a higher risk of the onset of symptoms after 1 month (odds ratio, 2.69; 95% CI, 1.19-6.07; P = .016). The use of an amino acid-based formula and the presence of diarrhea at admission were associated with later development of tolerance (P = .023 and P < .001, respectively). An IgE-mediated reaction was observed during oral food challenge testing in 6% of the patients.

CONCLUSIONS

The manifestations of FPIAP appeared earlier in premature infants and later in infants using formula. The use of amino acid-based formula and having had diarrhea were associated with delayed tolerance.

IgE-Mediated food allergy: Current diagnostic modalities and novel biomarkers with robust potential

Food allergy (FA) is a serious public health issue afflicting millions of people globally, with an estimated prevalence ranging from 1-10%. Management of FA is challenging due to overly restrictive diets and the lack of diagnostic approaches with high accuracy and prediction. Although measurement of serum-specific antibodies combined with patient medical history and skin prick test is a useful diagnostic tool, it is still an imprecise predictor of clinical reactivity with a high false-positive rate. The double-blind placebo-controlled food challenge represents the gold standard for FA diagnosis; however, it requires large healthcare and involves the risk of acute onset of allergic reactions. Improvement in our understanding of the molecular mechanism underlying allergic disease pathology, development of omics-based methods, and advances in bioinformatics have boosted the generation of a number of robust diagnostic biomarkers of FA. In this review, we discuss how traditional diagnostic modalities guide appropriate diagnosis and management of FA in clinical practice, as well as uncover the potential of the latest biomarkers for the diagnosis, monitoring, and prediction of FA. We also raise perspectives for precise and targeted medical intervention to fill the gap in the diagnosis of FA.

HLA-II Alleles Influence Physical and Behavioral Responses to a Whey Allergen in a Transgenic Mouse Model of Cow's Milk Allergy

The symptoms of food allergies vary significantly between individuals, likely due to genetic determinants. In humans, allergy development is initiated by antigen-presenting cells via class II human leukocyte antigen (HLA-II). The HLA-II gene is highly polymorphic, and its allelic variance is thought to influence the susceptibility of individuals to a particular allergen. However, whether antigen presentation by different HLA-II variants contributes to symptom variation is not clear. We hypothesized that HLA-II allelic variance affects symptom phenotypes, including immediate physical reactions and delayed behavioral changes, in individuals with food hypersensitivity. To test our hypothesis, male and female mice of three transgenic strains expressing an HLA-II variant, DR3, DR15, or DQ8, were used to establish a cow's milk allergy model. Mice were sensitized to a bovine whey allergen, β-lactoglobulin (BLG; Bos d 5), weekly for 5 weeks, followed by an acute oral allergen challenge. At 30 min post-challenge, BLG-sensitized DR3 mice showed moderate to severe anaphylaxis resulting in perioral redness, swelling, and death. In contrast, DQ8 and DR15 mice were generally asymptomatic. The production of allergen-specific immunoglobulins was also HLA- and sex-dependent. Both male and female DR3 and female DR15 mice significantly increased BLG-specific IgE production, while robust elevation in BLG-specific IgG1 was observed in sensitized DQ8 mice of both sexes and, to a lesser extent, in DR15 males. Furthermore, BLG-sensitized DR15 mice showed sex-specific behavior changes, with males exhibiting mobility changes and anxiety-like behavior and females showing spatial memory impairment. When splenocytes from transgenic mice were stimulated in vitro with BLG, phenotypes of immune cells were HLA- and sex-specific, further underscoring the influence of HLA-II on immune responses. Our results support that HLA-II alleles influence behavioral responses in addition to immune and physical reactions of food allergy, suggesting that certain HLA-II variants may predispose individuals to food-allergy-associated behavioral changes.

Patterns of Clinical Reactivity in a Danish Cohort of Tree Nut Allergic Children, Adolescents, and Young Adults

Background

Tree nut allergy is associated with severe reactions and poly-sensitization to other nuts and peanuts often occurs. There are regional differences in sensitization profiles that result in differences in clinical presentation. Denmark is located in a birch pollen endemic area, which could influence the allergy patterns due to pollen cross-sensitization.

Objective

This study aimed to investigate patterns of sensitization and clinical reactivity to tree nuts and peanuts and threshold levels for oral food challenges (OFCs) in a Danish cohort of tree nut allergic children, adolescents, and young adults.

Methods

Forty tree nut allergic subjects were assessed for clinical reactivity to six nuts, i.e., hazelnut, walnut, pistachio, cashew, almond, and peanut, by OFCs or convincing medical history of an immediate allergic reaction or tolerance. Clinical presentation and allergen-specific immunoglobulin E (sIgE) levels together with eliciting dose and rescue medication in OFCs were furthermore assessed.

Results

Allergy to two or more tree nuts was observed in most cases. Hazelnut-walnut dual allergy was common but not exclusively observed as concomitant allergies. Allergy to cashew was coincided in all but one of the assessed subjects with pistachio allergy. Half of all assessed subjects were allergic to peanuts. Oral symptoms followed by a skin reaction were the most common symptomatology that lead to OFC cessation and subjects often presented with symptoms from two or more organ systems. OFC threshold levels were within the same range, but cashew was distinguished from other nuts by causing allergic symptoms at the lowest dose. Clinical reactivity and the allergy patterns were to some extent reflected by sIgE levels and by correlations in sIgE between the nuts.

Conclusions

In this Northern European cohort, subjects with clinically relevant tree nut allergy were generally allergic to two or more tree nuts and close to half of them also to peanuts. There were two distinct and independent allergic phenotypes; the majority of hazelnut allergic subjects were also allergic to walnut, and all but one subject with cashew allergy were dual allergic to pistachio. These findings are consistent with a strong sIgE correlation between hazelnut and walnut and a close to total sIgE correlation between cashew and pistachio.

Dysfunction of S100A4+ effector memory CD8+ T cells aggravates asthma

Progressive loss of effector functions, especially IFN-γ secreting capability, in effector memory CD8⁺ T (CD8⁺ T_EM ) cells plays a crucial role in asthma worsening. However, the mechanisms of CD8⁺ T_EM cell dysfunction remain elusive. Here, we report that S100A4 drives CD8⁺ T_EM cell dysfunction, impairing their protective memory response and promoting asthma worsening in an ovalbumin (OVA)-induced asthmatic murine model. We find that CD8⁺ T_EM cells contain two subsets based on S100A4 expression. S100A4⁺ subsets exhibit dysfunctional effector phenotypes with increased proliferative capability, whereas S100A4^- subsets retain effector function but are more inclined to apoptosis, giving rise a dysfunctional CD8⁺ T_EM cell pool. Mechanistically, S100A4 upregulation of mitochondrial metabolism results in a decrease of acetyl-CoA levels, which impair the transcription of effector genes, especially ifn-γ, facilitating cell survival, tolerance and memory potential. Our findings thus reveal general insights into how S100A4 CD8⁺ T_EM cells reprogram into dysfunctional and less protective phenotypes to aggravate asthma. This article is protected by copyright. All rights reserved.

Tolerance induction through early feeding to prevent food allergy in infants with eczema (TEFFA): rationale, study design, and methods of a randomized controlled trial

Background

Up to 8% of all children in industrialized countries suffer from food allergies, whereas children with atopic eczema are affected considerably more frequently. In addition, the type and starting time of weaning foods seem to influence the development of food allergies. However, data from interventional studies on weaning are controversial.

The aim of this randomized-controlled clinical trial is to investigate, whether an early introduction of hen's egg (HE), cow’s milk (CM), peanut (PN), and hazelnut (HN) in children with atopic eczema can reduce the risk for developing food allergies in the first year of life.

Methods

This is a protocol for a randomized, placebo controlled, double blind, single-center clinical trial.

One hundred fifty infants with atopic eczema at 4–8 months of age will be randomized in a 2:1 manner into an active group that will receive rusk-like biscuit powder with HE, CM, PN, and HN (initially approximately 2 mg of each food protein) for 6–8 months or a placebo group, whose participants will receive the same rusk-like biscuit powder without HE, CM, PN, and HN on a daily basis. During the interventional period, the amount of allergens in the study product will be increased three times, each after 6 weeks. All study participants who are sensitized to HE, CM, PN, or HN at the end of the interventional period will undergo an oral food challenge to the respective food in a further visit.

Primary endpoint is IgE-mediated food allergy to at least one of the four foods (HE, CM, PN or HN) after 6–8 months of intervention (i.e., at around 1 year of age). Secondary endpoints include multiple food allergies, severity of eczema, wheezing, and sensitization levels against food allergens.

Discussion

This clinical trial will assess whether an early introduction of allergenic foods into the diet of children with atopic eczema can prevent the development of food allergies. This trial will contribute to update food allergy prevention guidelines.

Trial registration

German Clinical Trials Register DRKS00016770. Registered on 09 January 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06126-x.

Atopic Dermatitis and Food Allergy: Best Practices and Knowledge Gaps-A Work Group Report from the AAAAI Allergic Skin Diseases Committee and Leadership Institute Project

Allergists are often asked to evaluate children with atopic dermatitis (AD) for allergen triggers to disease. Testing, particularly for food triggers, often leads to elimination diets in an effort to improve AD control. However, the dual exposure hypothesis suggests that oral tolerance to food antigens is promoted through high-dose oral exposure, where sensitization occurs through lower dose cutaneous exposure. This suggests that strict elimination diets may pose some risks in children with AD. In addition, emerging evidence suggests an important role of skin inflammation in further allergic disease and the importance of dietary exposure to maintain oral tolerance. This work group report reviews current guidelines-based management for children with moderate-to-severe AD, the evidence for current recommendations for the evaluation and management of these children, provides a nuanced examination of these studies, and addresses current knowledge gaps in the care of these children.