How Different Parts of the World Provide New Insights Into Food Allergy

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

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

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.

Additive or Interactive Associations of Food Allergies with Glutathione S-Transferase Genes in Relation to ASD and ASD Severity in Jamaican Children

To investigate additive and interactive associations of food allergies with three glutathione S-transferase (GST) genes in relation to ASD and ASD severity in Jamaican children. Using data from 344 1:1 age- and sex-matched ASD cases and typically developing controls, we assessed additive and interactive associations of food allergies with polymorphisms in GST genes (GSTM1, GSTP1 and GSTT1) in relation to ASD by applying conditional logistic regression models, and in relation to ASD severity in ASD cases as measured by the Autism Diagnostic Observation Schedule-2nd Edition (ADOS-2) total and domains specific comparison scores (CSs) by fitting general linear models. Although food allergies and GST genes were not associated with ASD, ASD cases allergic to non-dairy food had higher mean ADOS-2 Restricted and Repetitive Behaviors (RRB) CS (8.8 vs. 8.0, P = 0.04). In addition, allergy to dairy was associated with higher mean RRB CS only among ASD cases with GSTT1 DD genotype (9.9 vs. 7.8, P < 0.01, interaction P = 0.01), and GSTP1 Val/Val genotype under a recessive genetic model (9.8 vs. 7.8, P = 0.02, interaction P = 0.06). Our findings are consistent with the role for GST genes in ASD and food allergies, though require replication in other populations.

Growing Up in Singapore with allergies - Lessons learnt from the GUSTO & S-PRESTO cohorts

Healthcare systems across the world face major challenges due to allergic diseases, known to affect people of all ages. In Singapore, two prominent cohort studies, Growing Up in Singapore Towards healthy Outcomes (GUSTO) and the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO), have made notable advancements to our knowledge and understanding of allergic diseases. These cohorts, which comprised of healthy mother-infant dyads recruited from the healthy Singapore population, have shed light on the complex connections between factors influencing health in early life, preconception and pregnancy, on the pathogenesis of allergic disorders in offspring. GUSTO highlighted significant risk factors in antenatal and early life, such as maternal diet, health and lifestyle choices, as well as infant environmental influences, that contributed to the risk of allergic diseases in the Asian Singaporean population. It also identified differential patterns of allergic disease in comparison to other populations, particularly the role of the microbiome in predicting atopic outcomes. Meanwhile, S-PRESTO further explores the long-term maternal and child outcomes associated with preconception health. Findings seem to suggest that prevention of offspring allergic conditions can be achieved through optimizing maternal health and lifestyle choices before conception. Both studies underscore the significance of early life interventions, preconception health, and personalized approaches to effectively manage and prevent allergies. By leveraging the insights and promising findings from GUSTO and S-PRESTO, future work can drive development of preventative strategies and personalized interventions to reduce burden of allergic diseases in the Singapore population.

History and Utility of Specific IgE Cutoff Levels: What is the Relevance for Allergy Diagnosis?

Allergy is defined clinically, by symptoms on allergen exposure. A patient is considered sensitized when allergen-specific IgE (sIgE) antibody can be detected in serum or plasma or a skin test result is positive, even if no clinical reaction has been experienced. Sensitization should be regarded as a requisite and risk factor for allergy but is not synonymous with an allergy diagnosis. To provide a correct allergy diagnosis, test results regarding allergen-sIgE must always be considered in view of the patient's case history and clinical observations. Correct assessment of a patient's sensitization to specific allergens relies on the use of accurate and quantitative methods for detection of sIgE antibodies. The evolution of sIgE immunoassays toward higher analytical performance and the use of different cutoff levels in the interpretation of test results sometimes cause confusion. Earlier versions of sIgE assays offered a limit of quantitation of 0.35 kilounits of sIgE per liter (kUA/L), which also became an established cutoff level for a positive test result in the clinical use of the assays. Current sIgE assays are capable of reliably measuring sIgE levels as low as 0.1 kUA/L and can thereby demonstrate sensitization in cases in which previous assays could not. When the outcome of sIgE test results is evaluated, it is critically important to distinguish between the analytical data as such and their clinical interpretation. Even though sIgE may be present in the absence of symptoms of allergy, available information suggests that sIgE concentrations between 0.1 kUA/L and 0.35 kUA/L may be clinically relevant in some individuals, not least among children, although this should be further evaluated for various allergies. Moreover, it is becoming widely adopted that nondichotomous interpretation of sIgE levels may offer a diagnostic benefit compared with using a predefined cutoff level.

Filling Analytical Gaps in Allergen Detection─Real-Time PCR for the Detection of Commercially Relevant Cephalopods and Gastropods in Food

Mollusks belong to the group of shellfish, which are considered to be among the elicitors of severe food allergies worldwide. In recent years, numerous PCR detection methods have been developed for other shellfish such as crustaceans. However, cephalopods and gastropods were not considered in the development of these shellfish detection systems. In this study, we have developed highly specific real-time PCR methods for the comprehensive detection of all commercially relevant cephalopod species and the gastropod families Helicidae, Buccinidae, and Muricidae in food matrices. In total, we cross-tested over 100 animal and plant species to show the specificity of our systems. The limit of detection (LOD12) was set at 1 pg of cephalopod and gastropod DNA or 10 ppm (mg/kg) spiked in a vegetarian food product. The robustness of the protocol was confirmed by testing multiple parameters while cooking and autoclaving of samples ensured the practical applicability of the systems.

Birth order, sibship size, and risk of atopic dermatitis, food allergy, and atopy: A systematic review and meta-analysis

BACKGROUND

Atopic dermatitis and food allergy are two frequently concomitant manifestations of the presence of atopy. A substantial number of studies have been published on the association of birth order and sibship size (number of siblings) with atopic dermatitis, food allergy, and atopy. The present work is the first systematic synthesis of the existing literature on this topic.

METHODS

Fifteen databases were searched. Screening, data extraction, and quality assessment were performed by independent pairs. Comparable numerical data were statistically synthesized using random-effects robust variance estimation.

RESULTS

In total, 114 studies were included out of 8819 papers obtained from database searches. Birth order ≥2 versus 1 was associated with lower risk of ever atopic dermatitis (pooled risk ratio [RR] 0.91, 95% CI 0.84-0.98), current food allergy (RR 0.77, 95% CI 0.66-0.90), and positive skin prick test (SPT) to common aeroallergens (RR 0.86, 95% CI 0.77-0.97). Sibship size ≥2 versus 1 was associated with decreased risk of current atopic dermatitis (RR 0.90, 95% CI 0.83-0.98), ever atopic dermatitis (RR 0.92, 95% CI 0.86-0.97), and positive SPT to common aeroallergens (RR 0.88, 95% CI 0.83-0.92). No putative associations were seen regarding atopy assessed through allergen-specific immunoglobulin E with common allergens.

CONCLUSION

The presence of siblings and being second-born or later may decrease the lifetime risk of atopic dermatitis and food allergy, albeit marginally. Similar association was seen with SPT sensitization. However, significant protection was not found for IgE sensitization.

Advances and potential of omics studies for understanding the development of food allergy

The prevalence of food allergy continues to rise globally, carrying with it substantial safety, economic, and emotional burdens. Although preventative strategies do exist, the heterogeneity of allergy trajectories and clinical phenotypes has made it difficult to identify patients who would benefit from these strategies. Therefore, further studies investigating the molecular mechanisms that differentiate these trajectories are needed. Large-scale omics studies have identified key insights into the molecular mechanisms for many different diseases, however the application of these technologies to uncover the drivers of food allergy development is in its infancy. Here we review the use of omics approaches in food allergy and highlight key gaps in knowledge for applying these technologies for the characterization of food allergy development.

Allergic sensitization to foods in India and other Low-Middle-income countries

Food allergy is an important cause of morbidity, significantly affecting the quality of life of the sufferer. Most food allergy research has been undertaken in high-income countries. Here, we summarize literature regarding food allergy in India and other low-middle-income countries (LMIC). We provide summaries of self-reported adverse food reactions and food sensitization in these regions by reviewing published community-based studies of prevalence, burden, and risk factors. We identified 2 community-based studies of food allergy prevalence in Karnataka, India, which estimate that food allergy affects just 0.14% of children and 1.2% of adults. The overall prevalence of allergic sensitization to 'any' food was 26.5% in adults and 19.1% in children by serum-specific IgE; but only 4.48% in children by skin prick test. We identified a further 28 studies in other LMICs, mainly from China but also Turkey, South Africa, Ghana, Mexico, Brazil, Thailand, Philippines, and Korea. The overall prevalence of allergic sensitization to 'any' food ranged from 0.11% to 16.8% in children using serum-specific IgE and 0.14% to 9.6% in children by skin prick test. The questionnaires and skin prick testing materials used and number of allergens tested varied significantly between studies. Other than Karnataka, there is no information on prevalence of food sensitization and probable food allergy in the community in India. Similar lack of information is noted among the majority of the 136 LMICs. Where community-based studies have been undertaken, there is wide variation in the prevalence and patterns of food sensitization across different LMICs, at least partly due to variations in study methodology. International collaboration is required in order to formally assess food allergy prevalence and burden across representative samples from multiple LMICs.

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.

IgE Mediated Wheat Allergy Associated with Resistant and Severe Forms of Allergic Conjunctivitis

Objective:

This study aimed to determine the prevalence and criteria of wheat allergy (WA) among patients with resistant allergic conjunctivitis (AC).

Methods:

A prospective comparative study was conducted on 100 patients with resistant AC. Skin prick-tests (SPTs), total and sIgE against a panel of inhalant and food allergens were performed in all patients’ sera. They were divided into 2 groups according to skin prick test (SPT) and specific IgE (sIgE) level, namely the wheat sensitive group (WSG) and wheat tolerant group (WTG). Total ocular symptom scores (TOSS) and 4-point sign scales were correlated for both groups.

Results:

Ten patients out of 100 with IgE-mediated resistant AC were wheat sensitive, and the other 90 were wheat tolerant patients. WSG included patients of significantly younger age. Positive family history of atopy was proven in 100% of WSG vs. 67% of WTG. A significantly higher frequency of multiorgan allergy was detected in 100% of WSG vs. 20% in WTG (P = 0.0001). Thirty (30%) of WSG had associated allergic rhinitis (AR) and bronchial asthma (BA). Another 30% had an associated AR only, 10% had an associated BA only, and another 20% had an associated skin allergy. TOSS, 4- point sign scale, and total IgE level were significantly higher in WSG.

Conclusion:

This study provides novel evidence that wheat allergy is responsible for some severe forms of AC.

Qualitative interviews to understand health care providers' experiences of prescribing licensed peanut oral immunotherapy

Objective

This research sought to explore health care providers’ (HCPs) experiences of delivering the first US Food and Drug Administration (FDA) and European Commission (EC) approved peanut oral immunotherapy (peanut OIT; Palforzia). Semi-structured qualitative interviews with HCPs who had initiated treatment with ≥ 3 patients in the first nine months following FDA approval sought to identify challenges faced and successful implementation strategies.

Results

Eight allergists and three nurse practitioners from eight sites based in the United States participated. The HCPs included in this research were motivated to implement this novel treatment, however, entered the process with some reservations. HCPs described how successful implementation of peanut OIT requires them to be thoughtful about their clinic’s abilities to integrate complex, time-consuming treatments into their daily practice. Prior experience of OIT was deemed beneficial, but not essential for implementation and learning from others’ experience was suggested as a way of helping new prescribers overcome perceived and actual implementation challenges. Delivering licensed peanut OIT during the COVID-19 pandemic posed both challenges and unexpected opportunities for implementation. The experiences described have the potential to benefit the wider allergy community by providing practical solutions, successful implementation strategies and opportunities to enhance training and resources.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-022-06161-6.

Current insights: a systemic review of therapeutic options for peanut allergy

PURPOSE OF REVIEW

With increasing prevalence of peanut allergy (PA) globally and the greater risk of potential reactions occurring due to the leading role of nuts in food products, PA has become a significant public health concern over the past decade, affecting up to 5 million of the US adult population. This review details updates and advances in prevalence, diagnosis, and immunotherapies that have occurred over the past year.

RECENT FINDINGS

Therapeutic and diagnostic advances remain at the forefront of research and have continued to push the food allergy (FA) field forward to provide a promising role in the detection and treatment of PA. The FA field has researched significant advances in peanut immunotherapy, biomarker diagnosis, and quality of life (QoL) improvement.

SUMMARY

Given the burden and consequences for individuals with PA, these advances delivered in clinical practice can significantly improve the QoL of individuals with PA and their caregivers. Ongoing studies will continue to investigate long-term outcome measures of desensitisation and effective management plans tailored to the families' needs.

[Peculiarities of allergy to plant foods in South-Eastern Spain]

Allergy to fruits and vegetables is the most common primary food allergy in Mediterranean countries, especially the lipid transfer proteins (LTPs) syndrome. This study is the first research that studies multiple clinical, allergological and therapeutics characteristics of allergies to plants in the South-East of Spain, and assessing whether these characteristics differ in emergency room or outpatient clinic. This is a prospective study of patients who consult for the first time for allergy to vegetables at Granada, Spain. We record demographic data, symptoms, allergological study and indicated therapy. The characteristics obtained agree with the current bibliographic except the higher prevalence than other areas of positive sensitization of Pru p 3, Cor a 9 and Ara h 9, which predisposes to severe allergic reactions. We conclude: Allergy to plant food in Granada is a more severe phenotype than other geographic areas from Spain, especially in young adults sensitized by different LTPs and pollinosis to olive pollen.

Eight tips for the implementation of the first licenced peanut allergy oral immunotherapy into clinical practice

BACKGROUND

Shared learnings from the early use of novel therapies can aid in their optimization. The recent introduction of peanut oral immunotherapy (peanut OIT; Palforzia [Peanut (Arachis hypogaea) Allergen Powder-dnfp]) for peanut allergy addresses a significant unmet need but also highlights the requirement for consideration of several factors by both prescribers and patients.

OBJECTIVE

To provide guidance for prescribers of licenced peanut OIT to facilitate treatment delivery and improve outcomes.

METHODS

Clinicians with experience of licenced peanut OIT (United States n = 6, United Kingdom n = 1) participated in a series of interviews and group discussions designed to elicit tips for successful implementation.

RESULTS

Clinicians identified 8 tips that were considered the most relevant, practical, and impactful for prescribers of Peanut (Arachis hypogaea) Allergen Powder-dnfp: (1) preparing to provide treatment, (2) assessing the medical indication for treatment and (3) shared decision making, (4) staff education, (5) establishing office processes, (6) managing patient expectations and using anticipatory guidance, (7) optimising adherence and (8) maintaining flexibility throughout the treatment process. In addition, a range of supporting materials (e.g., checklists and action plans) are provided.

CONCLUSION

The introduction of a novel therapy often requires healthcare providers to modify or adopt practices to effectively employ the treatment. The provision of guidance based upon early real-world experiences of licenced peanut OIT may help inform clinical practice and improve treatment outcomes.

Probiotic strains alleviated OVA-induced food allergy in mice by regulating the gut microbiota and improving the level of indoleacrylic acid in fecal samples

Food allergy (FA) is a common immune disorder caused by food antigens. Probiotic strains showed alleviating effects on FA, such as the alleviation of FA pathological symptoms, serum OVA-sIgE levels, and the gut microbiota diversity and composition. The results showed that intragastric administration of Lactiplantibacillus plantarum CCFM1189, Limosilactobacillus reuteri CCFM1190, and Bifidobacterium longum CCFM1029 alleviated the weight loss and FA pathological symptoms of FA mice and decreased OVA-specific IgE and histamine (HIS) levels. CCFM1189 and CCFM1190 decreased IL-4, IL-5, and IL-13 levels, while CCFM1189 and CCFM 1029 decreased IL-17 levels. The gut microbiota analysis demonstrated that CCFM1189 increased the abundance of Akkermansia, while CCFM1190 improved immune regulation bacteria such as Faecalibaculum. CCFM1029 increased Bifidobacterium and the bacteria involved in short-chain fatty acid (SCFA) production, such as Dubosiella. L. plantarum CCFM1189 and L. reuteri CCFM1190 improved indoleacrylic acid levels in mouse fecal samples using untargeted metabolomics analysis. In conclusion, CCFM1189, CCFM1190, and CCFM1029 decreased Th2 immune responses and alleviated FA pathological symptoms by regulating the gut microbiota diversity and composition, and altering gut microbial metabolites, which could provide support in clinical tests and probiotic production in the future.

Protocol for a systematic review of the diagnostic test accuracy of tests for IgE-mediated food allergy

BACKGROUND

The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of updating the guidelines on the diagnosis and management of food allergy. The existing guidelines are based on a systematic review of the literature until 30 September 2012. Therefore, a new systematic review must be undertaken to inform the new guidelines. This systematic review aims to assess the accuracy of index tests to support the diagnosis of IgE-mediated food allergy.

METHODS

The databases Cochrane CENTRAL (Trials), MEDLINE (OVID) and Embase (OVID) will be searched for diagnostic test accuracy studies from 1 October 2012 to 30 June 2021. Inclusion and exclusion criteria will be used to select appropriate studies. Data from these studies will be extracted and tabulated, and then reviewed for risk of bias and applicability using the QUADAS-2 tool. All evaluations will be done in duplicate. Studies with a high risk of bias and low applicability will be excluded. Meta-analysis will be performed if there are three or more studies of the same index test and food.

RESULTS

A protocol for the systematic review and meta-analyses is presented and was registered using Prospero prior to commencing the literature search.

DISCUSSION

Oral food challenges are the reference standard for diagnosis but involve considerable risks and resources. This protocol for systematic review aims to assess the accuracy of various tests to diagnose food allergy, which can be useful in both clinical and research settings.

Seafood Allergy in Asia: Geographical Specificity and Beyond

Asian countries have unique ways of food processing and dietary habits that may explain the observed differences in the prevalence, natural history, epidemiology and sensitization pattern of food allergic diseases when compared to western countries. Per capita consumption of seafood, including fish and shellfish, is well above the global average for many Asian countries because of their coastal geographical location and rich seafood supply. The wide availability and high abundance of seafood in Asian countries have shaped a diverse way of processing and eating this major food group. Such unique features have significant impact on the sensitization profile and allergenicity of Asians to fish and shellfish. For example, fish and shellfish are eaten raw in some countries that may promote sensitization to heat-labile allergens not otherwise seen in other regions. Fermented fish sauce is commonly used as a condiment in some countries which may promote fish sensitization. Shrimp head and shrimp roe are regarded as delicacies in some countries, but their allergen profiles are yet to be characterized. Freshwater fish and shellfish are a common food source in many Asian countries but the allergenicity of many such species remains unknown. In this review, we discuss factors that may contribute to differences in molecular profile and sensitization pattern for fish and shellfish that are observed in Asian populations and revisit the current status of seafood allergy in this part of the world. Acknowledging the similarities and differences of seafood allergy patterns between Asian and western populations can help us refine a better strategy for diagnosing and managing seafood allergy.

Diagnosis of mast cell activation syndrome: a global "consensus-2"

The concept that disease rooted principally in chronic aberrant constitutive and reactive activation of mast cells (MCs), without the gross MC neoplasia in mastocytosis, first emerged in the 1980s, but only in the last decade has recognition of "mast cell activation syndrome" (MCAS) grown significantly. Two principal proposals for diagnostic criteria have emerged. One, originally published in 2012, is labeled by its authors as a "consensus" (re-termed here as "consensus-1"). Another sizable contingent of investigators and practitioners favor a different approach (originally published in 2011, newly termed here as "consensus-2"), resembling "consensus-1" in some respects but differing in others, leading to substantial differences between these proposals in the numbers of patients qualifying for diagnosis (and thus treatment). Overdiagnosis by "consensus-2" criteria has potential to be problematic, but underdiagnosis by "consensus-1" criteria seems the far larger problem given (1) increasing appreciation that MCAS is prevalent (up to 17% of the general population), and (2) most MCAS patients, regardless of illness duration prior to diagnosis, can eventually identify treatment yielding sustained improvement. We analyze these proposals (and others) and suggest that, until careful research provides more definitive answers, diagnosis by either proposal is valid, reasonable, and helpful.

Developing National and International Guidelines

Food allergy (FA) is considered an emerging public health problem. The development of evidence-based guidelines aims to help health care professionals in an accurate diagnosis and management of such diseases. It is proven that there are differences in the factors that determine FA in the different regions of the world. It is necessary to encourage standardization processes of guidelines development. Nevertheless, in the future it will be necessary to take into consideration not only a methodologically correct analysis of the evidence but also the socio-economic realities where the guidelines will be applied.

Prevalence of Food-Hypersensitivity and Food-Dependent Anaphylaxis in Colombian Schoolchildren by Parent-Report

Background and objectives: The epidemiology of food allergy (FA) and food-dependent anaphylaxis remains unknown in Colombia. Our aim was to estimate by parent-report the prevalence of FA and food-dependent anaphylaxis in a Colombian population of schoolchildren. Materials and methods: A printed questionnaire was sent to parents of schoolchildren aged 5–12 years old from Medellín, Colombia in order to collect FA-related data. Results: Nine hundred and sixty-nine (969) parents returned the questionnaire with valid responses (response rate, 52.5%). The estimated prevalence rates (95% CI) were: adverse food reactions 12.79% (10.76–15.07), “perceived FA, ever” 10.93% (9.08–13.08), “physician-diagnosed FA, ever” 4.33% (3.14–5.81), “immediate-type FA, ever” 6.81% (5.30–8.58), “immediate-type FA, current” 3.30% (2.26–4.63), and food-dependent anaphylaxis 1.85% (1.10–2.92). The most frequently reported food allergens were milk (1.44%), fruits (0.41%), meat (0.41%), and peanut (0.3%). Sixty-one percent of “food-dependent anaphylaxis” cases sought medical attention, but only eleven percent of the cases reported the prescription of an epinephrine autoinjector. Conclusions: FA and food-dependent anaphylaxis are not uncommon among schoolchildren from Colombia. The prescription of epinephrine autoinjectors should be encouraged among health personnel for the optimal management of suspected cases of food-dependent anaphylaxis.

Current insights into the genetics of food allergy

Food allergy (FA), a growing public health burden in the United States, and familial aggregation studies support strong roles for both genes and environment in FA risk. Deepening our understanding of the molecular and cellular mechanisms driving FAs is paramount to improving its prevention, diagnosis, and clinical management. In this review, we document lessons learned from the genetics of FA that have aided our understanding of these mechanisms. Although current genetic association studies suffer from low power, heterogeneity in definition of FA, and difficulty in our ability to truly disentangle FA from food sensitization (FS) and general atopy genetics, they reveal a set of genetic loci, genes, and variants that continue to implicate the importance of barrier and immune function genes across the atopic march, and FA in particular. The largest reported effects on FA are from MALT1 (odds ratio, 10.99), FLG (average odds ratio, ∼2.9), and HLA (average odds ratio, ∼2.03). The biggest challenge in the field of FA genetics is to elucidate the specific mechanism of action on FA risk and pathogenesis for these loci, and integrative approaches including genetics/genomics with transcriptomics, proteomics, and metabolomics will be critical next steps to translating these genetic insights into practice.

Challenges of managing food allergy in the developing world

Food allergy (FA) is currently a significant health care problem in the developing world. Widely varying study populations and methodologies, the use of surrogate markers such as self report or hospitalization rates due to anaphylaxis rather than objective methods, limits robust estimation of FA prevalence in low income settings. Also, allergy is under-recognized as a clinical specialty in the developing world which compromises the chance for accurate diagnosis. In this review, most published data on food allergens from developing or low income countries are displayed. The diagnostic challenges and limitations of treatment options are discussed. It seems that FA is an under-appreciated health care issue in the developing world, and accurate determination of its burden in low-income settings represents an important unmet need. Multicenter surveillance studies, using standardized methodologies, are, therefore, needed to reveal the true extent of the problem and provide epidemiological clues for prevention. Preventive strategies should be tailored to fit local circumstances in different geographic regions. In addition, studying the gene environment interactions and impact of early life microbiota on the expression of FA in developing communities would be worthwhile. Efforts and resources should be directed toward public health education and training of health care providers dealing with food allergic patients.

Machine learning approach yields epigenetic biomarkers of food allergy: A novel 13-gene signature to diagnose clinical reactivity

BACKGROUND

Current laboratory tests are less than 50% accurate in distinguishing between people who have food allergies (FA) and those who are merely sensitized to foods, resulting in the use of expensive and potentially dangerous Oral Food Challenges. This study presents a purely-computational machine learning approach, conducted using DNA Methylation (DNAm) data, to accurately diagnose food allergies and potentially find epigenetic targets for the disease.

METHODS AND RESULTS

An unbiased feature-selection pipeline was created that narrowed down 405,000+ potential CpG biomarkers to 18. Machine-learning models that utilized subsets of this 18-feature aggregate achieved perfect classification accuracy on completely hidden test cohorts (on an 8-fold hidden dataset). Ensemble classification was also shown to be effective for this High Dimension Low Sample Size (HDLSS) DNA methylation dataset. The efficacy of these machine learning classifiers and the 18 CpGs was further validated by their high accuracy on a large number of hidden data permutations, where the samples in the training, cross-validation, and hidden sets were repeatedly randomly allocated. The 18-CpG signature mapped to 13 genes, on which biological insights were collected. Notably, many of the FA-discriminating genes found in this study were strongly associated with the immune system, and seven of the 13 genes were previously associated with FA.

CONCLUSIONS

Previous studies have also created highly-accurate classifiers for this dataset, using both data-driven and a priori biological insights to construct a 96-CpG signature. This research builds on previous work because it uses a completely computational approach to obtain a perfect classification accuracy while using only 18 highly discriminating CpGs (0.005% of the total available features). In machine learning, simpler models, as used in this study, are generally preferred over more complex ones (other things being equal). Lastly, the completely data-driven methodology presented in this research eliminates the need for a priori biological information and allows for generalizability to other DNAm classification problems.

[Research advances in influencing factors for immune tolerance to food allergens in children]

Food allergen-specific immune tolerance is defined as nonresponsiveness of the adaptive immune system to food antigens. Failed development or inhibition of such tolerance may cause food allergy. With the increasing incidence rate of food allergy year by year, more and more studies have found the association between food allergy and various diseases. The development of food allergen-specific immune tolerance in childhood has been taken more and more seriously. In recent years, many studies have shown that the development of food allergen-specific immune tolerance is influenced by various factors, which can be roughly divided into antigens, organisms, and environment. This article reviews the influencing factors for the development of immune tolerance to food allergens in children, in order to provide help for reducing the incidence of food allergy and improving the prognosis of food allergy.

Maternal Perinatal Dietary Patterns Affect Food Allergy Development in Susceptible Infants

BACKGROUND

The increasing incidence of food allergy (FA) can be attributed to interactions between genes and the environment, but these interactions are not yet fully clear.

OBJECTIVE

We aimed to evaluate the interaction between infant genetic variations and maternal dietary patterns to identify risk factors in the development of FA.

METHODS

We used the Cohort for Childhood Origin of Asthma and allergic diseases birth cohort of 1628 infants, born between 2007 and 2015. Maternal dietary intakes were assessed at 26 weeks of pregnancy using a food frequency questionnaire and grouped according to 5 dietary patterns. Infant cord blood samples were genotyped at 12 loci.

RESULTS

Among 1628 infants, 147 (9.0%) were diagnosed with FA based on history. A maternal confectionery diet characterized by a higher intake of baked and sugary products during pregnancy was associated with a higher prevalence of FA (adjusted odds ratio [OR] = 1.517, P = .02); this dietary pattern tended to be higher in trans fat (r = 0.498, P < .001). Development of FA was associated with longer periods of breastfeeding (adjusted OR = 1.792, P = .03), and this dietary pattern was more significantly related to the development of FA in infants with the homozygous TT genotype of CD14 (rs2569190) and more than 1 copy of GSTM1 and GSTT1.

CONCLUSIONS

A maternal confectionery diet during pregnancy that majorly consists of baked and sugary products, combined with a longer ensuing period of breastfeeding, may lead to the development of FA, suggesting a harmful effect of trans fats in the infant. Polymorphisms in CD14 and GST in the infant influence FA susceptibility.

Complementary Participation of Genetics and Epigenetics in Development of NSAID-exacerbated Respiratory Disease

Nonsteroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (NERD) has attracted a great deal of attention because of its association with severe asthma. However, it remains widely underdiagnosed in asthmatics as well as the general population. Upon pharmacological inhibition of cyclooxygenase 1 by NSAIDs, production of anti-inflammatory prostaglandin E2 and lipoxins ceases, while release of proinflammatory cysteinyl leukotrienes increases. To determine the underlying mechanisms, many studies have attempted to elucidate the genetic variants, such as single nucleotide polymorphisms, responsible for alterations of prostaglandins and leukotrienes, but the results of these genetic studies could not explain the whole genetic pathogenesis of NERD. Accordingly, the field of epigenetics has been introduced as an additional contributor to genomic alteration underlying the development of NERD. Recently, changes in CpG methylation, as one of the epigenetic components, have been identified in target tissues of NERD. This review discusses in silico analyses of both genetic and epigenetic components to gain a better understanding of their complementary roles in the development of NERD. Although the molecular mechanisms underlying NERD pathogenesis remain poorly understood, genetic and epigenetic variations play significant roles. Our results enhance the understanding of the genetic and epigenetic mechanisms involved in the development of NERD and suggest new approaches toward better diagnosis and management.

Peanut (Arachis hypogaea L.): A Prospective Legume Crop to Offer Multiple Health Benefits Under Changing Climate

Peanut is a multipurpose oil-seed legume, which offer benefits in many ways. Apart from the peanut plant's beneficial effects on soil quality, peanut seeds are nutritious and medicinally and economically important. In this review, insights into peanut origin and its domestication are provided. Peanut is rich in bioactive components, including phenolics, flavonoids, polyphenols, and resveratrol. In addition, the involvement of peanut in biological nitrogen fixation is highly significant. Recent reports regarding peanut responses and N₂ fixation ability in response to abiotic stresses, including drought, salinity, heat stress, and iron deficiency on calcareous soils, have been incorporated. As a biotechnological note, recent advances in the development of transgenic peanut plants are also highlighted. In this context, regulation of transcriptional factors and gene transfer for the development of stress-tolerant peanut genotypes are of prime importance. Above all, this review signifies the importance of peanut cultivation and human consumption in view of the scenario of changing world climate in order to maintain food security.