Peanut-induced anaphylaxis in children and adolescents: Data from the European Anaphylaxis Registry

Food-triggered anaphylaxis in adults

PURPOSE OF REVIEW

Adult food allergy, either unresolved from childhood, or new-onset in adult-life, is known to be increasingly prevalent. Although much of the reported anaphylaxis in adults is due to drug reactions, foods are becoming an increasingly important trigger, affecting adults of all ages, with a wide variation in food triggers which are often quite different to those reported in children.

RECENT FINDINGS

Peanuts are well known to cause anaphylaxis in some adult populations, but other legumes such as soy may be more relevant in others. Reactions to natto, fermented soybeans, are currently mainly reported in Japan, but changing dietary practices and an increase in plant-based eating mean natto, other forms of soy and other legumes are increasingly linked to anaphylaxis in Western countries. Anaphylaxis to red meat, caused by sensitization to galactose-α-1,3-galactose and first reported in North America, is now a more world-wide concern. Co-factor induced anaphylaxis is increasingly associated with both wheat allergy and lipid transfer protein allergy.

SUMMARY

More research is urgently needed to characterize adult food allergy, its triggers and symptom severity. Unusual food triggers and potential co-factors should be considered, so that anaphylaxis in adults can be correctly managed, not merely labelled as idiopathic.

Anaphylaxis: A 2023 practice parameter update

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

A case-control study for comorbidity and laboratory factors associated with food-induced anaphylaxis

Background: Food-induced anaphylaxis (FIA) is a serious and potentially life-threatening allergic reaction triggered by food allergens. Objective: This case-control study aimed to investigate comorbidities and laboratory factors associated with FIA in the pediatric population of Israel. Methods: Retrospective data from the electronic health records of Leumit Health Care Services were used to identify 711 pediatric patients with FIA and 2560 subjects with food allergy and without anaphylaxis matched for age, gender, and ethnicity. Comorbidities were identified based on medical billing diagnosis codes, and laboratory characteristics were compared between the two groups. Results: The mean ± standard deviation age of patients with FIA was 4.1 ± 4.1 years, and 37.3% were girls. Laboratory analysis revealed increased eosinophil counts (p < 0.001), elevated immunoglobulin E (IgE) (p < 0.001), and IgA levels (p = 0.001) in the FIA group compared with the controls. With regard to comorbidities, the FIA group had higher prevalence rates of allergic diseases, including allergic rhinitis (odds ratio [OR] 1.72; p < 0.001), allergic conjunctivitis (OR 1.84; p = 0.001), asthma (OR 1.36; p < 0.001), angioedema (OR 6.37; p < 0.001), atopic dermatitis (OR 1.77; p < 0.001), and contact dermatitis (OR 1.42; p = 0.001). There was a trend toward significance for chronic spontaneous urticaria (p = 0.051). There was a significant negative association between helminthiases, particularly enterobiasis, and FIA (OR 0.76 [95% confidence interval, 0.59-0.98]; p = 0.029). Conclusion: This study provides valuable epidemiologic evidence on the associations among FIA, comorbidities, and laboratory factors in the pediatric population.

Immune signatures predicting the clinical outcome of peanut oral immunotherapy: where we stand

Peanut allergy is a growing health concern that can cause mild to severe anaphylaxis as well as reduced quality of life in patients and their families. Oral immunotherapy is an important therapeutic intervention that aims to reshape the immune system toward a higher threshold dose reactivity and sustained unresponsiveness in some patients. From an immunological point of view, young patients, especially those under 3 years old, seem to have the best chance for therapy success. To date, surrogate markers for therapy duration and response are evasive. We provide a comprehensive overview of the current literature state regarding immune signatures evolving over the course of oral immunotherapy as well as baseline immune conditions prior to the initiation of treatment. Although research comparing clinical and immune traits in the first years of life vs. later stages across different age groups is limited, promising insights are available on immunological endotypes among peanut-allergic patients. The available data call for continued research to fill in gaps in knowledge, possibly in an integrated manner, to design novel precision health approaches for advanced therapeutic interventions in peanut allergy.

Preventing food allergy fatalities

Fatal anaphylaxis to food is thankfully rare, but every death is a potentially avoidable tragedy. Usually, there will be a coronial inquest to establish the 'how and why' for each death. Reviewing these food allergy-related deaths identifies a number of common themes and risk factors. While some are non-modifiable (such as age, gender and ethnicity), others are and include delayed epinephrine administration and communication difficulties in allergen avoidance. This review highlights the key messages in food allergy-related fatality prevention for healthcare professionals and patients alike, and where available, we explain the evidence behind such recommendations. We describe the data behind the good practice points to facilitate their adoption in routine practice without generating additional anxiety for what is a comparatively rare event. We also propose an information leaflet for patients and carers, developed with patients and endorsed by two major allergy charities, to facilitate dissemination of the recommendations in this review.

Food-Induced Anaphylaxis: Data From the European Anaphylaxis Registry

BACKGROUND

Food is one of the most common elicitors of anaphylaxis, with an increasing incidence over recent years.

OBJECTIVES

To characterize elicitor-specific phenotypes and identify factors enhancing the risk or severity of food-induced anaphylaxis (FIA).

METHODS

We analyzed data from the European Anaphylaxis Registry applying an age- and sex-matched analysis of associations (Cramer's V) for single food triggers and calculated odds ratios (ORs) for severe FIA.

RESULTS

We identified 3,427 cases of confirmed FIA showing an age-dependent elicitor ranking (for children: peanut, cow's milk, cashew, and hen's egg; and for adults: wheat flour, shellfish, hazelnut, and soy). The age- and sex-matched analysis revealed defined symptom patterns for wheat and cashew. Wheat-induced anaphylaxis was more frequently associated with cardiovascular symptoms (75.7%; Cramer's V = 0.28) and cashew-induced anaphylaxis with gastrointestinal symptoms (73.9%; Cramer's V = 0.20). Furthermore, concomitant atopic dermatitis was slightly associated with anaphylaxis to hen's egg (Cramer's V = 0.19) and exercise was strongly associated with anaphylaxis to wheat (Cramer's V = 0.56). Additional factors influencing the severity were alcohol intake in wheat anaphylaxis (OR = 3.23; CI, 1.31-8.83) and exercise in peanut anaphylaxis (OR = 1.78; CI, 1.09-2.95).

CONCLUSIONS

Our data show that FIA is age-dependent. In adults, the range of elicitors inducing FIA is broader. For some elicitors, the severity of FIA seems to be related to the elicitor. These data require confirmation in future studies considering a clear differentiation between augmentation and risk factors in FIA.

Low-Dose Oral Challenge Test in Pediatric Patients With Peanut Allergy: Tolerance Assessment of a Trace 5 mg Peanut Test After Symptom Induction With a 500 mg Test

Introduction Peanut allergy (PA) represents a significant public health concern, particularly prevalent in Western countries. Children at high risk for PA may undergo a low-dose oral food challenge (OFC). However, if the result is positive, complete elimination of peanuts from the diet is recommended, and further trace OFC is typically not performed.  Material and methods This cross-sectional study retrospectively examined the rate of positive peanut OFC with a total peanut load of 5 mg in children who tested positive with a total peanut load of 500 mg. Patient information was gathered from medical records. The primary endpoint was the rate at which children who tested positive in the OFC with 500 mg of peanut butter also tested positive with 5 mg of peanut butter equivalent.  Results Among 32 children who underwent an OFC with a total peanut load of 500 mg, two were excluded for not meeting the criteria. Among the remaining 30 children, 14 (46.7%) had a positive 500 mg peanut OFC test, and three (10%) experienced an anaphylactic reaction. Those who tested positive for the OFC had higher peanut-specific and Ara h2-specific immunoglobulin E (IgE) antibodies. An OFC with 5 mg of peanuts performed on 10 of the 14 patients who tested positive for 500 mg of peanuts showed no positive results. Conclusion The results of this study suggest that children with severe PA who exhibit positive symptoms to a total peanut load of 500 mg can tolerate a 5 mg dose of peanuts and should be considered for an OFC.

Cofactors in food anaphylaxis in adults

Around 25% to 50% of food-induced allergic reactions in adults cause anaphylaxis, and epidemiologic evidence suggests that food is the most common cause of anaphylaxis. Reaction severity is unpredictable, and patients will often experience reactions of variable severity, even to an identical exposure (both dose and allergen). A common explanation for this phenomenon has been the impact of "cofactors"-factors that might contribute to reaction severity independent of the allergen exposure. Cofactors can influence reaction severity in 2 ways: either by reducing the reaction threshold (ie, the dose needed to trigger any symptoms) so that patients have no symptoms in the absence of the cofactor and only react with the cofactor present, or by increasing reaction severity such that individuals have only mild symptoms in the absence of the cofactor, but a more severe reaction when the cofactor is present. Indeed, the same patient may have reactions with different cofactors or even need more than one cofactor to develop a severe reaction. Cofactors reportedly play a role in approximately 30% of anaphylaxis reactions in adults. Exercise, nonsteroidal, anti-inflammatory drugs, alcohol, and sleep deprivation are the most frequent cofactors reported. Routine evaluation of the possible involvement of cofactors is essential in managing patients with food anaphylaxis: in patients with a suggestive history but a negative oral food challenge, cofactors should be taken into account to provide appropriate advice to reduce the risk of future anaphylaxis.

[Characterization of patients with anaphylaxis in a tertiary hospital in Medellin, Colombia (2009-2019)]

OBJECTIVE

To characterize demographically and clinically the patients with anaphylaxis treated in a third level health institution in Medellin, Colombia.

METHODS

A cross-sectional descriptive observational study was carried out, which includedpatients were diagnosed with anaphylaxis between 2009 and 2019. Information was retrieved from medical records through a collection instrument. Subsequently, a descriptive statistical analysis of proportions and measures of central tendency of the variables of interest was performed.

RESULTS

A total of 1820 records were reviewed and data from 253 patients were included. Among the reported comorbidities, drug allergy was the most prevalent (28%). The most frequent manifestations of anaphylaxis were cutaneous and respiratory. Most of the cases presented basal tryptase values ≤ 11.4 ng/mL (94.7%). Different etiological agents (food, drugs, insects and latex) were reported, and their frequency varied according to age. Adrenaline, steroids, and antihistamines were the treatments of choice in 39.9, 34.3, and 39.9% of cases, respectively.

CONCLUSIONS

The characteristics of anaphylaxis in a medical center in Colombia coincide with those reported in Latin American. The treatment of anaphylaxis is not standardized, which makes it necessary to educate the health personnel and develop national guidelines.

Phase 3 Trial of Epicutaneous Immunotherapy in Toddlers with Peanut Allergy

BACKGROUND

No approved treatment for peanut allergy exists for children younger than 4 years of age, and the efficacy and safety of epicutaneous immunotherapy with a peanut patch in toddlers with peanut allergy are unknown.

METHODS

We conducted this phase 3, multicenter, double-blind, randomized, placebo-controlled trial involving children 1 to 3 years of age with peanut allergy confirmed by a double-blind, placebo-controlled food challenge. Patients who had an eliciting dose (the dose necessary to elicit an allergic reaction) of 300 mg or less of peanut protein were assigned in a 2:1 ratio to receive epicutaneous immunotherapy delivered by means of a peanut patch (intervention group) or to receive placebo administered daily for 12 months. The primary end point was a treatment response as measured by the eliciting dose of peanut protein at 12 months. Safety was assessed according to the occurrence of adverse events during the use of the peanut patch or placebo.

RESULTS

Of the 362 patients who underwent randomization, 84.8% completed the trial. The primary efficacy end point result was observed in 67.0% of children in the intervention group as compared with 33.5% of those in the placebo group (risk difference, 33.4 percentage points; 95% confidence interval, 22.4 to 44.5; P<0.001). Adverse events that occurred during the use of the intervention or placebo, irrespective of relatedness, were observed in 100% of the patients in the intervention group and 99.2% in the placebo group. Serious adverse events occurred in 8.6% of the patients in the intervention group and 2.5% of those in the placebo group; anaphylaxis occurred in 7.8% and 3.4%, respectively. Serious treatment-related adverse events occurred in 0.4% of patients in the intervention group and none in the placebo group. Treatment-related anaphylaxis occurred in 1.6% in the intervention group and none in the placebo group.

CONCLUSIONS

In this trial involving children 1 to 3 years of age with peanut allergy, epicutaneous immunotherapy for 12 months was superior to placebo in desensitizing children to peanuts and increasing the peanut dose that triggered allergic symptoms. (Funded by DBV Technologies; EPITOPE ClinicalTrials.gov number, NCT03211247.).

Factors associated with home epinephrine-treated reactions during peanut and tree-nut oral immunotherapy

BACKGROUND

Home reactions requiring epinephrine administration, a marker of their severity, restrict the widespread use of oral immunotherapy (OIT), but their risk factors are largely not known.

OBJECTIVE

To identify risk factors for such reactions during OIT to most allergenic foods.

METHODS

All patients who began OIT for peanut, tree nuts, sesame, or egg allergy at the Shamir Medical Center between April 2010 and January 2020 were enrolled. The patients were instructed to use their epinephrine autoinjectors during reactions consisting of severe abdominal pain, significant shortness of breath, or lethargy, or whenever in uncertainty of reaction severity. Patients with and without home epinephrine-treated reactions (HETRs) were compared.

RESULTS

A total of 757 OIT treatments for peanut (n = 346), tree nuts (n = 221; walnut n = 147, cashew n = 57, hazelnut n = 16, almond n = 1), sesame (n = 115), and egg (n = 75) allergies were administered to 644 patients. Eighty-three (10.9%) patients experienced HETRs. The highest rate of HETRs was experienced during walnut (20.4%) or hazelnut (25%) OIT, followed by peanut (9.8%), sesame (6.1%), egg (6.7%), and cashew (5.3%) OIT. Risk factors for HETRs included a reaction treated in an emergency department (ER) (P = .005) before starting OIT and a reaction treated with epinephrine during in-clinic induction (P < .001). Significantly fewer patients with (73.6%) than without (88.3%) HETRs achieved full desensitization (P = .001), but only a few patients with HETRs (8.4%) failed treatment.

CONCLUSION

Previous reaction severity is the main predictor for HETRs during OIT. These reactions are more frequent during walnut and hazelnut OIT than during OIT for other foods studied. Most patients experiencing HETRs achieved desensitization.

Cow's milk and hen's egg anaphylaxis: A comprehensive data analysis from the European Anaphylaxis Registry

BACKGROUND

Cow's milk (CM) and hen's egg (HE) are leading triggers of anaphylaxis in early childhood. The aim of this study was to identify clinical phenotypes and therapeutic measures for CM anaphylaxis (CMA) compared to HE anaphylaxis (HEA) in children up to 12 years of age, based on a large pan-European dataset from the European Anaphylaxis Registry.

METHODS

Data from 2007 to 2020 on clinical phenotypes and treatment from 10 European countries, as well as Brazil, were analysed. The two-step cluster analysis was used to identify the most frequent phenotypes. For each trigger, three clusters were extracted based on sex, age, and existence of symptoms in four vitally important systems.

RESULTS

Altogether 284 children with CMA and 200 children with HEA were identified. They were characterised as male (69% vs. 64%), infants (65% vs. 61%), with a most frequent grade III of Ring&Messmer classification (62% vs. 64%), in CMA versus HEA, respectively. Respiratory symptoms occurred more often in CMA (91% vs. 83%, p = 0.010), especially in infants (89% vs. 79%, p = 0.008). Cardiovascular symptoms were less frequent in CMA (30% vs. 44%, p = 0.002), in both infants (33% vs. 46%, p = 0.027), and older children (25% vs. 42%, p = 0.021). The clusters extracted in the CMA group were characterised as: (1) mild dermal infants with severe GI (40%), 2. severe dermal (35%), 3. respiratory (25%). While in HEA group: 1. infants with severe GI and/or reduction of alertness (40%), (2) conjunctival (16%), (3) mild GI without conjunctivitis (44%). The severity of the reaction was independent from the amount of ingested allergen protein, regardless of trigger. The first-line adrenaline application differed between the countries (0%-92%, as well as the reasons for not administering adrenaline, p < 0.001).

CONCLUSIONS

Despite the similarity of their age, sex, and severity grade, the clinical profiles differed between the CMA and HEA children. Adrenaline was underused, and its administration was country dependent. Further studies are needed to assess to what extent the differences in the clinical profiles are related to matrix and/or absorption effects, and/or the allergen itself.

Varying Approaches to Management of IgE-Mediated Food Allergy in Children Around the World

Food allergy is a chronic disease that affects individuals of all ages and is a significant public health problem globally. This narrative overview examines clinical management strategies for IgE-mediated food allergy in children around the world to understand variations in practice. Information was drawn from clinical practice guidelines, recent research, the websites of professional and governmental bodies with expertise in food allergy, and clinical experts from a broad cross-section of geographical regions. The structure and delivery of clinical services, allergen avoidance and food labeling, and resources to support the management of allergic reactions in the community are discussed in detail. The adoption of emerging food immunotherapies is also explored. Wide variations in clinical management of food allergy were apparent across the different countries. Common themes were continuing issues with access to specialist care and recognition of the need to balance risk reduction with dietary and social restrictions to avoid unnecessary detrimental impacts on the quality of life of food allergy sufferers. Findings highlight the need for standardized presentation of practice and priorities, and may assist clinicians and researchers when engaging with government and funding agencies to address gaps.

Endpoints and Outcomes After Immunotherapy for Food Allergy: What Is Meaningful for Patients?

Multiple novel interventions for food allergy are currently at various stages of development with the goal of reducing or eliminating allergic reactions. However, the relative success of these therapeutics in achieving meaningful, long-term improvements to patients' lives is difficult to determine as there is currently very limited understanding of the degree of alignment between clinical trial efficacy endpoints and patient-centered outcomes. Furthermore, outcome measures used in clinical trials of food allergy immunotherapies vary widely, are often misinterpreted, and not necessarily consistent with what patients expect to achieve through treatment. This review aims to assist clinicians in critically interpreting outcomes reported in clinical trials and accurately communicating risks and outcomes to patients when practicing shared decision-making.

Management of IgE-mediated food allergy in the 21st century

The 21st century has seen the propulsion of research in the field of food allergy, which has driven real changes in the clinical approach. Allergen immunotherapy has been recommended for the active management of food allergy. Data have shown promising additional methods of treatment, including biologics. Efforts have been devoted to the risk stratification of food allergy and the standardization of the assessment of food-allergic severity. Alternative routes of administration of epinephrine are under investigation to minimize any mechanical issue and the fear of injections. Evidence-based guidelines have been published by the main international societies in the field of anaphylaxis and food allergy management and new updates are in preparation. In the coming years, treatment options that are currently in pre-clinical or early clinical evaluation will hopefully lead to safe and effective disease-modifying therapies for food allergy in clinical practice. The identification of reliable biomarkers and the standardization of definitions and measurement approaches, alongside a shared decision-making with patients and families, will be key for the development of personalized care and to help minimize the substantial burden of food allergy.

Omalizumab in IgE-Mediated Food Allergy: A Systematic Review and Meta-Analysis

BACKGROUND

A growing number of studies have shown encouraging results with omalizumab (OMA) as monotherapy and as an adjunct to oral immunotherapy (OMA+OIT) in patients with single/multiple food allergies.

OBJECTIVES

To evaluate the efficacy and safety of OMA or OMA+OIT in patients with immunoglobulin E (IgE)-mediated food allergy.

METHODS

An extensive literature search (inception to December 31, 2020) was performed to identify randomized, controlled, and observational studies that assessed OMA as monotherapy or OMA+OIT in patients with IgE-mediated food allergy. The outcomes were an increase in tolerated dose of foods, successful desensitization, sustained unresponsiveness, immunological biomarkers, severity of allergic reactions to food, quality of life (QoL), and safety. A P less than .05 was considered significant.

RESULTS

In total, 36 studies were included. The OMA monotherapy (vs pre-OMA) significantly increased the tolerated dose of multiple foods; increased the threshold of tolerated dose for milk, egg, wheat, and baked milk; improved QoL; and reduced food-induced allergic reactions (all P < .01). The OMA+OIT significantly increased the tolerated dose of multiple foods (vs placebo and pre-OMA), desensitization (vs placebo+OIT and pre-OMA) (all P ≤ .01), and improved QoL (vs pre-OMA) and immunoglobulin G4 levels (both P < .01). No major safety concerns were identified.

CONCLUSIONS

In IgE-mediated food allergy, OMA can help patients consume multiple foods and allow for food dose escalation. As an adjunct to OIT, OMA can also support high-dose desensitization and higher maintenance doses. Further studies are warranted to empirically evaluate the effect of OMA and confirm these findings.

An update on anaphylaxis and urticaria

Notable scientific developments have taken place in the field of anaphylaxis and urticaria in recent years; they are highlighted in this review. Case-control studies, genome-wide association studies, and large omics analyses have promoted further insights into not only the underlying genetics but also the biomarkers of both anaphylaxis and urticaria. New evidence regarding IgE-dependent and non-IgE-dependent mechanisms of anaphylaxis and urticaria, including the Mas-related G protein-coupled receptor (MRGPR [formerly MRG]) signaling pathway, has been gained. Putative elicitors of anaphylactic reactions in the context of coronavirus disease 2019 (COVID-19) vaccination and impact of the COVID-19 pandemic on the management and course of chronic urticaria have been reported. Clinical progress has also been made regarding the severity grading and risk factors of anaphylaxis, as well as the distinction of phenotypes and elicitors of both diseases. Furthermore, novel treatment approaches for anaphylaxis and subtypes of urticaria have been assessed, with different outcome and potential for a better disease control or prevention.

Overview of registries for anaphylaxis: a scoping review

OBJECTIVE

This review aimed to describe the scope and operational features of anaphylaxis registries, and to assess their contribution to improving knowledge of anaphylaxis and care of patients who experience anaphylaxis by measuring their research output.

INTRODUCTION

Structured data collection and reporting systems, such as registries, are needed to better understand the burden of anaphylaxis and to protect the growing number of patients with severe allergy. There is a need to characterize current anaphylaxis registries to identify their value in anaphylaxis surveillance, management, and research. Information synthesized in this review will provide knowledge on benefits and gaps in current registries, which may inform the implementation and global standardization of future anaphylaxis reporting systems.

INCLUSION CRITERIA

This scoping review considered literature describing registries worldwide that enroll patients who have experienced anaphylaxis. Published and gray literature sources were included if they described the scope and operational features of anaphylaxis registries.

METHODS

This review followed the JBI methodology for scoping reviews. Embase, MEDLINE, Scopus, and CINAHL were searched for relevant articles. Identified keywords and index terms were adapted for searches of gray literature sources, using Google advanced search functions. Only full-text studies in English were considered for inclusion. Two independent reviewers conducted title and abstract screening and those that did not meet the inclusion criteria were excluded. The full text of potentially relevant articles were retrieved; full-text screening and data extraction were also conducted by two independent reviewers. Any discrepancies were resolved through discussion or with a third reviewer. Tables and a narrative summary were used to describe and compare the scope and features (eg, inclusion criteria, patient demographics, clinical symptoms) of the identified anaphylaxis registries, and to outline their output to assess their contribution to research and clinical practice for anaphylaxis.

RESULTS

A total of 77 full-text publications and eight gray literature sources were used to extract data. The literature search identified 19 anaphylaxis registries, with sites in 28 countries including Europe, the United Kingdom, Canada, the United States, Korea, and Australia. The main purposes of the identified registries were to collect clinical data for research; provide clinical support tools to improve patient care; and operate as allergen surveillance systems to protect the wider community with allergies. Differences in inclusion and health care settings exist, with 11 collecting data on anaphylaxis of any cause, two on food reactions alone, three on fatal anaphylaxis, one on perioperative anaphylaxis, and two on allergic reactions (including anaphylaxis). Five registries enroll cases in allergy centers, five in hospital settings, one in schools, and others target a combination of general practitioners, specialists in emergency departments, and other relevant hospital departments and allergy outpatient clinics. Only three registries operate under a mandatory framework. A total of 57 publications were considered research outputs from registries. All registries except two have published studies from collected data, with the greatest number of articles published from 2019 to the present. Publications mostly addressed questions regarding demographic profile, causes and cofactors, severity, fatal reactions, and gaps in management.

CONCLUSIONS

This review demonstrated that anaphylaxis registries differ in their scope and operation, having been established for different purposes. Importantly, registries have contributed significantly to research, which has highlighted gaps in anaphylaxis management, provoking allergens, and informed targets for prevention for severe and fatal events. Beyond this, registries relay information about anaphylaxis to clinicians and regulatory bodies to improve patient care and protect the community. The ability to link registry data with other health datasets, standardization of data across registries, and incorporation of clinical care indicators to promote quality health care across the health system represent important targets for future systems.

An interdisciplinary approach to characterize peanut-allergic patients-First data from the FOOD@ consortium

Background

Peanut allergy is a frequent cause of food allergy and potentially life-threatening. Within this interdisciplinary research approach, we aim to unravel the complex mechanisms of peanut allergy. As a first step were applied in an exploratory manner the analysis of peanut allergic versus non-allergic controls.

Methods

Biosamples were studied regarding DNA methylation signatures, gut microbiome, adaptive and innate immune cell populations, soluble signaling molecules and allergen-reactive antibody specificities. We applied a scalable systems medicine computational workflow to the assembled data.

Results

We identified combined cellular and soluble biomarker signatures that stratify donors into peanut-allergic and non-allergic with high specificity. DNA methylation profiling revealed various genes of interest and stool microbiota differences in bacteria abundances.

Conclusion

By extending our findings to a larger set of patients (e.g., children vs. adults), we will establish predictors for food allergy and tolerance and translate these as for example, indicators for interventional studies.

Risk factors for severe reactions in food allergy: Rapid evidence review with meta-analysis

This rapid review summarizes the most up to date evidence about the risk factors for severe food-induced allergic reactions. We searched three bibliographic databases for studies published between January 2010 and August 2021. We included 88 studies and synthesized the evidence narratively, undertaking meta-analysis where appropriate. Significant uncertainties remain with respect to the prediction of severe reactions, both anaphylaxis and/or severe anaphylaxis refractory to treatment. Prior anaphylaxis, an asthma diagnosis, IgE sensitization or basophil activation tests are not good predictors. Some molecular allergology markers may be helpful. Hospital presentations for anaphylaxis are highest in young children, yet this age group appears at lower risk of severe outcomes. Risk of severe outcomes is greatest in adolescence and young adulthood, but the contribution of risk taking behaviour in contributing to severe outcomes is unclear. Evidence for an impact of cofactors on severity is lacking, although food-dependent exercise-induced anaphylaxis may be an exception. Some medications such as beta-blockers or ACE inhibitors may increase severity, but appear less important than age as a factor in life-threatening reactions. The relationship between dose of exposure and severity is unclear. Delays in symptom recognition and anaphylaxis treatment have been associated with more severe outcomes. An absence of prior anaphylaxis does not exclude its future risk.

Beliefs about food allergies in adolescents aged 11-19 years: A systematic review

Aims

Research suggests of people with food allergy (FA), adolescents have the highest risk of fatal allergic reactions to food, yet understanding of this population and how they manage their condition is limited. Understanding beliefs and how they affect behaviour could inform ways to reduce risk taking behaviour and fatal reactions in adolescents. This systematic review aimed to explore beliefs adolescents hold about their FA, and how these may be associated with FA management.

Demographics

Adolescents aged 11-19 years with FA.

Methodology

A systematic search of seven databases was conducted. Papers of any design were included that reported on the beliefs about FA in adolescents aged 11-19 years. Data was systemised by narrative thematic analysis.

Findings

20 studies were included. Themes included navigating FA in different environments, carriage and use of adrenaline auto-injectors, management of the risk of anaphylaxis, behaviour and understanding of others, and food-allergic identity.

Implications

Adolescents with FA hold a variety of condition beliefs; some beliefs were related to behaviour that could lead to an allergic reaction, while other beliefs were related to protective behaviours. Further research into understanding adolescent beliefs in order to inform clinical management and reduce the risk of potential fatal reactions is essential.

[Role of vegan diets in food allergies-risk of developing food anaphylaxis?]

We report about a 28-year-old woman with an anaphylactic reaction to falafel. The diagnosis of type 1 allergy to peas was made based on the detailed medical history, the sensitization profile and an oral food challenge. Pea (Pisum sativum) is a legume that is increasing used, for example, as protein flour in vegetarian and vegan food products. In addition to the case report, we discuss the anaphylaxis risk of food used in the vegan diet.

Early-life predictors and risk factors of peanut allergy, and its association with asthma in later-life: Population-based birth cohort study

BACKGROUND

Understanding risk factors for peanut allergy (PA) is essential to develop effective preventive measures.

OBJECTIVE

To ascertain associates and predictors of PA, and the relationship between PA and asthma severity.

METHODS

In a population-based birth cohort, we investigated the association between objectively confirmed PA with early-life environmental exposures, filaggrin (FLG)-loss-of-function mutations and other atopic disease. We then examined the association of PA with longitudinal trajectories of sensitisation, wheeze and allergic comorbidities, which were previously derived using machine learning. Finally, we ascertained the relationship between PA and asthma severity.

RESULTS

PA was confirmed in 30/959 participants with evaluable data. In the multivariate analysis, eczema in infancy (OR=4.4, 95% CI 1.5-13.2, p=0.007), egg sensitisation at age 3 years (OR=9.7, 95% CI 3.3-29.9, p<0.001) and early-life cat ownership (OR=3.0, 95% CI 1.1-8.4, p=0.04) were independent associates of PA. In the stratified analysis among 700 participants with genetic information, in children with early-life eczema there was no difference in FLG mutations between children with and without PA (3/18 [16.7%] vs. 42/220 [19.1%], p=1.00). In contrast, among children without eczema, those with PA were almost 8-times more likely to have FLG mutations (2/6 [33.3%] vs. 27/456 [5.9%], p=0.049). We observed associations between PA and multiple allergic sensitisation profiles derived using machine learning, with ~60-fold increase in risk amongst individuals assigned to multiple early sensitisation. PA was significantly associated with persistent wheeze (but not other wheeze phenotypes), and with trajectories of atopic disease characterised by co-morbid persistent eczema and wheeze (but not with transient phenotypes). Children with PA were more likely to have asthma, but among asthmatics we found no evidence of an association between PA and asthma severity.

CONCLUSIONS

Peanut allergy is associated with multiple IgE-sensitisation and early-onset persistent eczema and wheeze. FLG loss-of-function mutations were associated with peanut allergy in children without eczema.

Primary prevention of food allergy in 2021: Update and proposals of French-speaking pediatric allergists

During the past years, there has been an alarming increase in cases of food allergy and anaphylaxis in ever-younger children. Often, these children have multiple food allergies and food sensitizations, involving allergens with high anaphylactic potential, such as peanuts and nuts, which have a major influence on their quality of life and future. After reviewing the current epidemiological data, we discuss the main causes of the increase in food allergies. We analyze data from studies on the skin barrier and its fundamental role in the development of sensitization and food allergies, data on the tolerogenic digestive tract applied in particular to hen eggs and peanuts, as well as data on the prevention of allergy to cow milk proteins. In light of these studies, we propose a practical guide of recommendations focused on infants and the introduction of cow milk, the management of eczema, and early and broad dietary diversification including high-risk food allergens, such as peanut and nuts while taking into account the food consumption habits of the family.

Recent update on the management of anaphylaxis

Anaphylaxis is a life-threatening systemic allergic reaction presenting various clinical manifestations. Its prevalence has increased in almost all age groups and both sexes. Food, venom, and drugs are major causes in both children and adults; a higher prevalence of food-induced anaphylaxis is noted in children, while a higher prevalence of drug-induced anaphylaxis is noted in adults. The pathogenic mechanism is mediated by immunologic and nonimmunologic mechanisms, where mast cells and basophils are key cells that release mediators. A diagnosis of anaphylaxis is mainly based on clinical symptoms and physical findings; however, an increased serum tryptase level is a useful biomarker. Epinephrine is the first-line drug to treat acute symptoms, and an epinephrine auto-injector should be prescribed for each patient. Antihistamines and systemic corticosteroids are used to relieve symptoms. This review updates current issues in the management of anaphylaxis as well as the new guidelines for proper diagnosis and treatment.