Incidence of food anaphylaxis in people with food allergy: a systematic review and meta-analysis

To the ER? Can Patients Treat Their Anaphylaxis at Home?

PURPOSE OF REVIEW

To discuss if all patients who use self-injectable epinephrine outside the hospital setting require immediate emergency care.

RECENT FINDINGS

Prior to 2023, anaphylaxis management guidance universally recommended that patients who use self-injectable epinephrine outside of the hospital or clinic setting immediately activate emergency medical services and seek further care. Additional food-induced anaphylaxis management recommendations specified that all patients always carry 2 auto-injector devices and give a second dose of epinephrine if there was not immediate response within 5 min of injection. Patients presenting for emergency care after epinephrine are often observed for up to 4-6 h afterwards, even when completely asymptomatic. These management steps have lacked evidence for improving outcomes, and universal implementation of these approaches is not cost-effective as guidance for food allergic patients. Epinephrine pharmacokinetics and pharmacodynamics suggest that peak physiologic response is more likely to occur closer to 15 min than before 5 min, that few patients require a second dose of epinephrine as most stabilize within 15 min of use, that 60 min of observation after a patient stabilizes after epinephrine use may be adequate as patients infrequently have further sequelae, and that not everyone needs to carry 2 epinephrine auto-injectors on their person at all times. The most recent anaphylaxis practice parameter promotes a contextualized approach to these management questions, outlining the option for watchful waiting to gauge response to epinephrine before seeking emergency care, which has been proven as a more cost-effective management strategy. The recent updated anaphylaxis care guidelines support the evolution of anaphylaxis care, in that universal, immediate activation of emergency services is not required for using self-injectable epinephrine outside the hospital setting.

Population-based incidence of all-cause anaphylaxis and its development over time: a systematic review and meta-analysis

Introduction

It is extremely difficult to compare studies investigating the frequency of anaphylaxis making it challenging to satisfactorily assess the worldwide incidence rate. Using a systematic review and meta-analysis, this publication aims to determine the current incidence of all-cause anaphylaxis worldwide. Additionally, we investigated whether the incidence of anaphylaxis has changed over time and which factors influence the rates determined by individual studies.

Methods

A literature search was performed in four databases. All articles that reported relevant information on population-based incidence rates of all-cause anaphylaxis were included. The protocol was published on INPLASY, the International Platform of Registered Systematic Review and Meta-analysis Protocols.

Results

The database query and screening process resulted in 46 eligible articles on anaphylaxis. The current incidence worldwide was found to be approximately 46 cases per 100,000 population per year (95% CI 21-103). Evaluating confounding factors showed that studies using allergy clinics and hospitalizations as data source result in comparably low rates. Moreover, children are less prone to develop anaphylaxis compared to the general population. Using a random effects Poisson model we calculated a yearly increase of anaphylaxis incidence by 7.4% (95% CI 7.3-7.6, p < 0.05).

Discussion

This seems to be the first approach to analyze every reported all-cause anaphylaxis incidence rate until 2017 for an at most accurate determination of its epidemiology. Based on these results, future research could investigate the underlying causes for the rising incidence in order find ways to decrease the condition's frequency.

Systematic Review Registration

inplasy.com, identifier [INPLASY202330047].

Allergenicity evaluation of quinoa proteins - A study in Brown Norway rats

The popularity of quinoa seeds has increased in the last decade due to their high nutritional value and natural gluten-free composition. Consumption of new proteins may pose a risk of introducing new allergies. In the present study the immunogenicity and sensitising capacity of quinoa proteins were assessed in a dose-response experiment in Brown Norway rats in comparison to proteins from spinach and peanut. Cross-reactivity between quinoa proteins and known allergens was evaluated by in silico analyses followed by analyses with 11 selected protein extracts and their anti-sera by means of ELISAs and immunoblotting. Further, an in vitro simulated gastro-duodenal digestion was performed. Quinoa proteins were found to have an inherent medium to high immunogenicity and sensitising capacity, being able to induce specific IgG1 and IgE levels higher than spinach but lower than peanut and elicit reactions of clinical relevance similar to peanut. Quinoa proteins were generally shown to resist digestion and retain capacity to bind quinoa-specific antibodies. Quinoa proteins were shown to be cross-reactive with peanut and tree nut allergens as high sequence homology and antibody cross-binding were demonstrated. Present study suggests that quinoa pose a medium to high level of allergenicity that should be further investigated in human studies.

How Common Are Allergic Reactions During Commercial Flights? A Systematic Review and Meta-Analysis

BACKGROUND

Global passenger demand for air travel has increased by over 7% annually since 2006, with a strong recovery following the coronavirus disease 2019 (COVID-19) pandemic. Prior to COVID-19, individuals with food allergies reported significant concern and anxiety over the risk of reactions when travelling by air. However, published data of in-flight medical events (IMEs) due to allergic reactions are limited.

OBJECTIVE

To undertake a systematic review with meta-analysis to estimate the incidence of IMEs due to allergic reactions on commercial flights.

METHODS

We searched MEDLINE, Embase, PsycINFO, and TRANSPORT databases and the Cochrane Register of Controlled Trials for relevant studies reporting IMEs of allergic etiology, published since 1980. Data were extracted in duplicate for meta-analysis, and risk of bias assessed.

STUDY REGISTRATION

PROSPERO CRD42022384341.

RESULTS

Seventeen studies met the inclusion criteria. At meta-analysis, a pooled estimate of 2.2% (95% confidence interval [95% CI] 1.6%-3.1%) of IMEs are coded as being due to allergic reactions. This may be higher in children (3.1%; 95% CI 1.5%-6.6%). The incidence of allergic IMEs at meta-analysis was 0.7 events per million passengers (95% CI 0.4-1.1). Reassuringly, the rate of allergic IMEs has been stable over the past 30 years, despite increasing passenger numbers and food allergy prevalence.

CONCLUSIONS

Allergic reactions coded as IMEs during commercial air travel are uncommon, occurring at an incidence approximately 10 to 100 times lower than that reported for accidental allergic reactions to food occurring in the community. Despite increasing passenger numbers and food allergy prevalence, the rate of allergic IMEs has not changed over the past 3 decades.

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.

Knowledge gaps in food allergy among the general public in Jeddah, Saudi Arabia: Insights based on the Chicago food allergy research survey

Background

Food allergy is an increasing health concern. Studies have shown that food allergy knowledge is lacking among people, especially in areas related to distinction between food allergy and intolerance, symptoms recognition, and current means of management. This knowledge gap puts allergic patients at more risk of getting fatal anaphylactic reactions, which occur mostly in public areas. Locally, Public's knowledge and attitudes of food allergy was not sufficiently investigated. Therefore, we aim to assess food allergy knowledge and attitudes among Jeddah population in Saudi Arabia.

Methods

We adopted The Chicago Food Allergy Research Survey for the General Public (CFARS-GP) and used it as a data collection tool. We hosted the questionnaire on Google Forms and distributed the link through social media outlets targeting individuals of Jeddah population who are 18 years old and above.

Results

A total of 510 individuals completed the survey. The respondents answered 56% of the knowledge-based items correctly. Knowledge was strongest in symptoms/severity and definition/diagnosis, while it was weakest in susceptibility and prevalence, distinction between food allergy and intolerance, and food allergy management. Higher knowledge was significantly associated with prior training in food allergy, food-allergic acquaintance (i.e., having food allergy or knowing an allergic patient), and being a relative of a health care worker. For the attitudes, respondents thought that food allergy negatively affects patients' quality of life, and that schools should establish policies to protect allergic children; however, they downplayed stigma associated with food allergy.

Conclusion

Increased food allergy knowledge among the general public is needed especially in areas related to susceptibility and prevalence, distinction between food allergy and intolerance, triggers and environmental risks, and the management of food allergy. Prior experience with food allergy through (1) training, (2) food-allergic acquaintance, or (3) being a relative of a health care worker increases food allergy knowledge significantly. Thus, targeted educational interventions might have a significant effect in improving food allergy knowledge among the general population.

Bridging Knowledge Gaps in Anaphylaxis Management Through a Video-Based Educational Tool

Introduction: We aimed to develop and test the effectiveness of an education tool to help pediatric patients and their families better understand anaphylaxis and its management, and to improve current knowledge and treatment guidelines adherence. Methods: From June 2019 to May 2022, 128 pediatric patients with history of food-triggered anaphylaxis who presented to the allergy outpatient clinics at the study institution were recruited. Consenting families were asked to complete 6 questions related to the triggers, recognition, and management of anaphylaxis at the time of presentation to the clinic. Participants were shown a 5-min animated video on the causes, presentation, and management of anaphylaxis. At the end of the video, the participants were redirected to the same 6 questions to respond again. The scores were recorded in proportion of correct answers (minimum 0.0; maximum 1.0). Results: The mean age of the patients was 5.8 ± 4.5 years (range: 0.5-18.8 years). The majority were males (70 patients; 54.7%). The mean baseline prevideo education questionnaire score was 0.76 ± 0.2 (range: 0.3-1.0), whereas the mean follow-up score was 0.82 ± 0.2 (range: 0.3-1.0). This score difference of 0.06 was statistically significant (P < 0.001). There were no significant associations between change in scores and age or gender of the participants. Conclusion: Our video teaching method was successful in educating patients and their families to better understand anaphylaxis and its management at the moment of the clinical encounter. Retention of knowledge at long-term follow-up should be assessed.

The Impact of Allergy Specialty Care on Health Care Utilization Among Peanut Allergy Children in the United States

BACKGROUND

The influence of allergist management on peanut allergy (PA)-related health care utilization is unknown.

OBJECTIVE

To determine whether allergist care lowers PA costs.

METHODS

IBM MarketScan Commercial Claims and Encounters Database was analyzed for PA diagnosis/reaction-related codes (January 2010-June 2019) in patients 64 years or younger, with demographically matched non-PA food allergy controls (NPAFACs). Outcomes were measured and compared 12 months before/after first claim date.

RESULTS

Among 72,854 persons with PA (39,068 with ≥1 allergist visit, 53.6%), and 166,825 NPAFACs, the number of National Drug Codes and International Classification of Diseases, 10th Revision codes was higher for persons with PA with versus without an allergist visit during both baseline and follow-up (all P < .001). Persons with PA with versus without an allergist visit were prescribed epinephrine at significantly higher rates (RR, 1.67; P < .001). Rates of epinephrine claims, mean epinephrine costs, and proportion with peanut anaphylaxis were higher among the PA group with versus without an allergist visit (69.9% vs 63.3%; $676 vs $493, 48.9% vs 20.7%; all P < .001). The proportion with anaphylaxis episodes was higher in the PA group versus the NPAFAC group (53.1% vs 31.6%; P < .001). Total health care costs were higher in the NPAFAC group versus the PA group ($7863 vs $7261; P < .001) and lower for persons with PA with versus without an allergist visit ($6347 vs $8270; P < .001), with no significant differences in PA reaction-related costs between PA groups.

CONCLUSIONS

Higher rates of anaphylaxis were seen among the PA group with versus without an allergist visit during the follow-up period (53.6% of overall PA group). Allergist care was associated with a reduction in total health care costs and higher rates of epinephrine prescription.

Anaphylaxis in Children and Adolescents: Greek Data Analysis from the European Anaphylaxis Registry (NORA)

The European Anaphylaxis Registry (NORA) was designed in order to create a comprehensive Anaphylaxis Registry regarding anaphylactic reactions characteristics and management in several European countries, including Greece. This study aims to analyze Greek data obtained in the NORA framework and describe anaphylaxis’ characteristics in this pediatric cohort. An online questionnaire was filled out by the Allergy Unit of the 2nd Pediatric Department of NKUA, regarding reported anaphylaxis characteristics. A total of 284 pediatric patients were analyzed. Patients were predominantly male. A previous, mild reaction (59.5%) to the same allergen was documented in 44.4% of patients. The most common system involved was skin and/or mucosa, followed by the respiratory system. Food was the most common eliciting factor (82.4%). First line treatment was most administered solely by a healthcare professional, followed by a lay person (38.7%). Auto injected adrenaline use by lay persons was third in frequency (29.2%). Most patients received post-reaction counseling and appropriate drug prescription. This study provides insight in anaphylactic cases’ characteristics and management in a Greek pediatric cohort. A low rate of adrenaline autoinjector administration was noted in lay people; however, drug prescription and counseling following the reaction could help increase correct acute anaphylaxis management in the future.

Analysis of the Serum Profile of Cytokines Involved in the T-Helper Cell Type 17 Immune Response Pathway in Atopic Children with Food Allergy

The main risk factor for the development of food allergies (FAs) in children is atopic dermatitis (AD). AD is usually recognized as the Th1/Th2 paradigm of allergic disease. Recently, the Th1/Th2 paradigm in allergy and autoimmunity has been revised, including the role of the Th17 cell population and related cytokines. However, there are only a few studies that have found Th17 cytokine involvement in the allergic inflammatory response, especially with food allergens. This research aimed to analyze the serum profile of cytokines involved in the T-helper cell type 17 immune response pathway in young, atopic children with an IgE-mediated and delayed-type FA. The study involved 76 children (0−5 years old) with chronic AD. We used the Bio-Plex system to simultaneously determine the concentrations of 15 different cytokines in one experiment. In accordance with complete dermatological and allergological examination, including OFC testing and ALEX2 assays, participants were divided into 3 groups: IgE-mediated FA, delayed-type FA, and the control group. Data were analyzed using univariate statistical tests. In the IgE-mediated FA group, the circulating levels of tested cytokines had increased compared with those of other patients; however, a statistically significant difference was only obtained for IL-1beta (p < 0.05). According to the ROC curves, IL-1beta may be considered an effective predictor of IgE-mediated FA in AD children (p < 0.05; AUC = 0.67). In the delayed-type FA group, the concentration of most cytokines had slightly decreased compared to the control group. The obtained results suggest that FA influences the Th17-related cytokine profile in the serum of AD children. More advanced studies are needed to confirm the involvement of Th17 cytokines in the allergic inflammatory response and to prove their usefulness in clinical practice.

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

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

Incidence of anaphylaxis and accidental peanut exposure: A systematic review

BACKGROUND

Peanut allergy (PA), a common food allergy, is increasing in prevalence and is associated with high rates of anaphylaxis. Prevalence of food-related anaphylaxis is higher in children and adolescents than in adults, and the pediatric incidence is increasing. We conducted a systematic literature review and meta-analysis to determine the incidence of peanut-induced anaphylaxis in children and/or adolescents with PA.

METHODS

Literature searches were conducted using the PubMed database and through supplemental methods. Eligible articles for inclusion were peer-reviewed studies published in English that reported the incidence of anaphylaxis in pediatric PA using the 2006 National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network criteria, sample size, and follow-up duration. Incidence rates were calculated as person-years at risk or a crude incidence rate was calculated. Meta-analyses of pooled data were conducted using the I² statistic as the measure of heterogeneity.

RESULTS

A total of 830 citations were screened; 8 met the study inclusion criteria and were selected for review. Pooled meta-analysis estimates of the incidence of (1) anaphylaxis among children/adolescents with food allergies, (2) anaphylaxis among children/adolescents with PA, and (3) accidental exposure to peanuts among children/adolescents with PA were 3.72 cases per 100 person-years (95% confidence interval [CI] = 2.35, 5.10), 2.74 cases per 100 person-years (95% CI = 1.42, 4.05), and 12.28 cases per 100 person-years (95% CI = 11.51, 13.05), respectively.

CONCLUSIONS

The risks of anaphylaxis among children with food allergies and those with PA contribute to the serious overall burden of PA and food allergy for children and their families.

Pediatric Anaphylaxis: Etiology and Predictive Factors in an Emergency Setting

Anaphylaxis is a serious allergic life-threatening condition that needs immediate treatment to prevent unfavorable outcomes. The present study revealed that the prevalence of anaphylaxis in children increased with age and the adolescent group has the most frequent anaphylaxis events. Food-induced anaphylaxis was the most common cause of anaphylaxis in pediatric population. This etiology revealed a significant correlation with a known history of food allergy in the study population, P = .029. Anaphylaxis from insect stings associated with cardiovascular symptoms, P < .001 and inclined to be severe. Univariate analysis showed predicted probability of severe anaphylaxis increased with age with an odds ratio of 1.1. This finding strengthens and supports the view that physicians should be aware of severe anaphylaxis reactions in older age group when there is a documented history of insect sting. The overall pediatric anaphylaxis patients in the study population had favorable outcomes. The authors recommended at least 24 hours hospital observation in order to observe biphasic reaction in pediatric anaphylaxis especially in adolescent age group.

Association Between Allergen Sensitization and Anaphylaxis in Patients Visiting a Pediatric Emergency Department

Background and Objectives: Anaphylaxis, a severe allergic disease, can be triggered by various causes. This study investigated the association between allergic sensitization and anaphylactic symptoms and the severity of anaphylaxis in children. Patients and Methods: A retrospective review of 107 pediatric patients with anaphylaxis was performed between January 1, 2015, and December 31, 2017; 74 patients underwent allergen testing for specific immunoglobulin E. Allergic sensitizations and associations with anaphylactic symptoms and severity were investigated. Results: Overall, 64 (86.5%) patients were sensitized to food or inhalant allergens. In children under 2 years of age, 90.5% were sensitized to food (P = 0.001); in those over 6 years of age, 84.6% were sensitized to inhalant allergens (P = 0.001). Milk sensitization was significantly associated with severe anaphylaxis (P = 0.036). The following symptoms showed significant associations with certain allergen sensitizations: facial edema with food; wheezing with milk; dyspnea with mite, etc. Certain allergen sensitizations presenting as risk factors for anaphylactic symptoms: wheat (adjusted odds ratio [aOR] = 4.644, P = 0.044) and nuts (aOR=3.614, P = 0.041) for wheezing, nuts (aOR=5.201, P = 0.026) for dyspnea, and milk (aOR=4.712, P = 0.048) for vomiting. Conclusion: The allergen sensitization status differed according to the age of the children experiencing anaphylaxis. The severity, symptoms, and signs of anaphylaxis differed depending on the allergen sensitization status.

Management of Peanut Allergy

Peanut allergy is a growing public health concern in westernized countries. Peanut allergy is characterized as an often severe and lifelong allergy, which can have detrimental effects on quality of life and trigger anxiety. Although multiple therapeutic options are emerging, the focus of current management strategies is strict peanut avoidance and carriage of self-injectable epinephrine. The greatest risk of reacting to peanut comes from direct ingestion, whereas casual skin contact or airborne exposure is highly unlikely to provoke significant symptoms. Patients and families must be educated about how to best execute strict peanut avoidance through careful label reading as well as how to understand and address likely and unlikely risk with regard to peanut exposure in public, in particular when dining outside of the home and for children attending school or child care. This review discusses the risk of exposure in public such as at school or on an airplane and how such risk can be abated, situations and scenarios when dining out of the house that may pose more risks than others, the essentials of US and EU label reading laws with particular emphasis on precautionary labeling and the risk implied by such, quality of life and psychosocial issues that may affect the peanut allergic individual and family, and a discussion of how risk may differ and evolve based on the patient's age.

Current perspectives on peanut allergy

Peanut allergy is increasingly prevalent and for most patients is a life-long condition, with the potential to cause life-threatening reactions. Accurate diagnosis and appropriate management are essential to minimise risks due to accidental peanut exposure. Current management strategies focus on strict allergen avoidance and access to emergency medicines to treat potential reactions; however, active approaches are an area of intense research. Promising new methods of food allergen immunotherapy are set to change the approach to managing peanut allergic patients in the near future.

Anaphylaxis and other allergic reactions to food: a global challenge

We describe a case of a biphasic anaphylactic reaction that occurred in a young woman soon after the ingestion of soy milk that led to her hospitalisation. Early recognition and appropriate treatment led to a successful outcome of this life-threatening condition. Challenges encountered in the care of this common illness are highlighted. There is a need for an increase in public awareness on dangerous allergic reactions caused by allergens present in food products in public use, thereby facilitating primary preventative measures to minimise its occurrence. Healthcare stakeholders need to implement measures of contemporary preventative medicine and efficient therapeutic protocols to safeguard the public welfare concerning this global health problem where appropriate interventions can reduce morbidity and mortality. Trial registration numbers NCT02991885 and NCT02851277.

CSACI guidelines for the ethical, evidence-based and patient-oriented clinical practice of oral immunotherapy in IgE-mediated food allergy

Background

Oral immunotherapy (OIT) is an emerging approach to the treatment of patients with IgE-mediated food allergy and is in the process of transitioning to clinical practice.

Objective

To develop patient-oriented clinical practice guidelines on oral immunotherapy based on evidence and ethical imperatives for the provision of safe and efficient food allergy management.

Materials and methods

Recommendations were developed using a reflective patient-centered multicriteria approach including 22 criteria organized in five dimensions (clinical, populational, economic, organizational and sociopolitical). Data was obtained from: (1) a review of scientific and ethic literature; (2) consultations of allergists, other healthcare professionals (pediatricians, family physicians, nurses, registered dieticians, psychologists, peer supporters), patients and caregivers; and patient associations through structured consultative panels, interviews and on-line questionnaire; and (3) organizational and economic data from the milieu of care. All data was synthesized by criteria in a multicriteria deliberative guide that served as a platform for structured discussion and development of recommendations for each dimension, based on evidence, ethical imperatives and other considerations.

Results

The deliberative grid included 162 articles from the literature and media reviews and data from consultations involving 85 individuals. Thirty-eight (38) recommendations were made for the practice of oral immunotherapy for the treatment of IgE mediated food allergy, based on evidence and a diversity of ethical imperatives. All recommendations were aimed at fostering a context conducive to achieving objectives identified by patients and caregivers with food allergy. Notably, specific recommendations were developed to promote a culture of shared responsibility between patients and healthcare system, equity in access, patient empowerment, shared decision making and personalization of OIT protocols to reflect patients' needs. It also provides recommendations to optimize organization of care to generate capacity to meet demand according to patient choice, e.g. OIT or avoidance. These recommendations were made acknowledging the necessity of ensuring sustainability of the clinical offer in light of various economic considerations.

Conclusions

This innovative CPG methodology was guided by patients' perspectives, clinical evidence as well as ethical and other rationales. This allowed for the creation of a broad set of recommendations that chart optimal clinical practice and define the conditions required to bring about changes to food allergy care that will be sustainable, equitable and conducive to the well-being of all patients in need.

Food reactions during avoidance: Focus on peanut

OBJECTIVE

Peanut allergy has historically been difficult to manage, with most cases persisting into adulthood. Novel therapies for peanut allergy treatment are on the horizon, yet allergists must maintain a robust understanding of the risks and benefits of the current standard of therapy, avoidance diet.

DATA SOURCES

A comprehensive literature search using PubMed of reviews and clinical articles was performed.

STUDY SELECTIONS

Articles discussing peanut or other food-related allergic reactions, accidental exposures or anaphylaxis pertinent to avoidance diet or comparative to oral immunotherapy trials were selected.

RESULTS

Peanut remains a leading allergen associated with accidental ingestions responsible for food-related reactions, both mild and severe. Fatal reactions, however, are rare and measures such as anaphylaxis plans can significantly decrease the risk of accidental anaphylaxis. Patients may over estimate situations thought to increase risk for reactions to peanut, such as inhalation or contact through skin. In oral immunotherapy trials, the rate of anaphylaxis secondary to treatment was significantly higher than avoidance practices.

CONCLUSION

Clinicians should continue to discuss avoidance as a viable option for long-term peanut allergy management and empower patients to differentiate relevant situations in which accidental reactions might occur.

Risk Factors for Hen's Egg Allergy in Europe: EuroPrevall Birth Cohort

BACKGROUND

Hen's egg is one of the commonest causes of food allergy, but there are little data on its risk factors.

OBJECTIVE

To assess the risk factors, particularly eczema, for hen's egg allergy in the EuroPrevall birth cohort.

METHODS

In the pan-European EuroPrevall birth cohort, questionnaires were undertaken at 12 and 24 months or when parents reported symptoms. Children with suspected egg allergy were invited for skin prick testing, specific IgE assessment, and double-blind, placebo-controlled food challenge (DBPCFC) as indicated. Each egg allergy case (positive DBPCFC or egg-induced anaphylaxis) was allocated up to 2 age- and country-matched controls.

RESULTS

A total of 12,049 infants were recruited into the EuroPrevall birth cohort, and 9,336 (77.5%) were followed until 2 years. A total of 86 infants had egg allergy (84 by DBPCFC) and were matched with 140 controls. Independently associated with egg allergy were past/current eczema (adjusted odds ratio, 9.21; 95% CI, 2.65-32.04), Scoring Atopic Dermatitis (1.54 per 5 units; 1.28-1.86), antibiotics in the first week of life (6.17; 1.42-26.89), and current rhinitis (3.02; 1.04-8.78). Increasing eczema severity was associated with an increasing likelihood of egg allergy. Eczema was reported to have started 3.6 (SE, 0.5) months before egg allergy. Age of introduction of egg into the diet was not associated with egg allergy.

CONCLUSIONS

Similar to peanut allergy, eczema was strongly associated with egg allergy development and the association increased with increasing eczema severity. The age of introduction of dietary egg was not a risk factor. The potential role of antibiotics in early life as a risk factor for egg allergy needs further examination.

T cell epitope of arginine kinase with CpG co-encapsulated nanoparticles attenuates a shrimp allergen-induced Th2-bias food allergy

T cell peptide-based immunotherapy (PIT) is an appealing therapeutic strategy for modulating allergic responses without IgE cross-linking. We propose a novel PIT that combines a T-cell epitope of the shrimp allergen arginine kinase (AKp) with TLR9 agonist CpG-ODN in nanoparticles (CpG-AKp NPs) to attenuate a shrimp allergen-induced food allergy. Treatment with CpG-AKp NPs demonstrated the attenuation of anaphylaxis responses such as the reduced incidence of diarrhea and hypothermia, lower levels of specific IgE and the induction of IgG2a in serum. Th2 cytokines were suppressed and higher Th1 cytokines were detected in the splenocyte culture supernatants. Treatment of CpG-AKp NPs also enhanced the protein expression of Foxp3 and IL-10 in small intestine but decreased the activation of STAT6 and GATA3 expression, which are related to differentiation of Th2. Our data indicated that CpG-AKp NPs may represent a promising PIT against shrimp allergy.

Anaphylaxis - Lessons learnt when East meets West

The rapidly increasing prevalence of allergic disorders over the past 2 decades highlights the need to understand the epidemiology of anaphylaxis. In Europe, the United States, and Australia, the incidence of anaphylaxis is estimated to be between 60 and 950 cases per 100 000 population, with a lifetime prevalence of anaphylaxis of 0.05%-2%. The incidence appears to be increasing over time. Although the existing Asian literature is heterogeneous and limited by under-reporting, it also suggests a similar increasing trend in anaphylaxis incidence in Asia. Anaphylaxis triggers in Asia, such as the predominance of shellfish and wheat in older children and adolescents, differ from those seen in Western populations. Triggers unique to Asia such as traditional Chinese medications, galacto-oligosaccharides, and food delicacies have also been reported. Low usage of adrenaline as first-line treatment of anaphylaxis is evident across all countries and is particularly concerning. There is a need to establish prospective, standardized protocols for anaphylaxis data collection and reporting, to enhance the collective understanding of anaphylaxis and its burden, gaps in management and to identify areas for future research and intervention in each region. Understanding of the underlying reasons explaining the difference between East and West will facilitate future primary preventive strategies.

The global incidence and prevalence of anaphylaxis in children in the general population: A systematic review

BACKGROUND

Despite an increasing number of publications from individual countries and regions, there is still no systematic review of the global epidemiology of anaphylaxis in the general paediatric population.

METHODS

We conducted a systematic review, using a protocol registered and published with the international prospective register of systematic reviews (PROSPERO). Results were reported following PRISMA guidelines. The search strategy was designed in Medline (ovid) and modified for Embase (ovid) and PubMed. Papers were screened by two independent reviewers following selection and exclusion criteria. Data extraction and risk of bias assessment were completed by the same two reviewers. Studies in adults only or those that did not report data in children separately were excluded.

RESULTS

A final total of 59 articles were included. Of these, 5 reported cumulative incidence, 39 reported incidence rate and 17 reported prevalence data. The incidence of anaphylaxis in children worldwide varied widely, ranging from 1 to 761 per 100 000 person-years for total anaphylaxis and 1 to 77 per 100 000 person-years for food-induced anaphylaxis. The definition of anaphylaxis from NIAID/FAAN was the most commonly used. Gender and ethnicity were demographic risk factors associated with anaphylaxis in children. Increasing total or food-induced anaphylaxis incidence over time was reported by 19 studies.

CONCLUSION

The reported incidence of anaphylaxis in children varied widely. Studies in developing countries are underrepresented. To accurately compare anaphylaxis incidence between countries and investigate the time trends, further studies using a standardized definition across different countries are required.

Estimation of Health and Economic Benefits of Commercial Peanut Immunotherapy Products: A Cost-effectiveness Analysis

IMPORTANCE

Commercial epicutaneous peanut immunotherapy (EPIT) and peanut oral immunotherapy (POIT) may offer significant quality-of-life improvements for patients with peanut allergy, but the cost-effectiveness of commercial peanut immunotherapies is uncharacterized.

OBJECTIVE

To evaluate critical inputs associated with the cost-effectiveness of EPIT and POIT from a societal perspective.

DESIGN, SETTING, AND PARTICIPANTS

Economic evaluation in which microsimulations with Markov modeling were performed evaluating virtual children aged 4 years over an 80-year time horizon. The base-case costs included a caregiver-reported willingness to pay of $3839 annually for safe and effective food allergy treatment. Estimates of predictive biomarkers or oral challenges were incorporated after the first year of therapy with additional analyses of immunotherapy risk reduction of anaphylaxis and probability of sustained unresponsiveness (SU) to peanut after 4 years.

EXPOSURES

Children received EPIT, POIT, or no immunotherapy treatment (n = 10 000 per treatment strategy).

MAIN OUTCOMES AND MEASURES

Rates of therapy-associated adverse reactions and quality-of-life improvements associated with changes in eliciting or tolerated peanut doses were modeled along with quality-adjusted life-years (QALYs), anaphylaxis, therapy-associated anaphylaxis, and fatalities.

RESULTS

In the base-case analysis without SU to peanut, the EPIT strategy cost less than POIT (mean [SD] cost, $154 662 [$46 716] vs $163 524 [$56 800]) and had fewer total episodes of anaphylaxis (mean [SD], 1.33 [1.55] vs 3.83 [5.02] episodes) and fewer episodes of therapy-associated anaphylaxis (mean [SD], 0.62 [1.30] vs 3.10 [4.94] episodes) but had lower QALY accumulation (mean [SD], 26.932 [2.241] vs 26.945 [2.320] QALYs). The incremental cost-effectiveness ratio was $216 061 for EPIT and $255 431 for POIT. Models were sensitive to therapy cost, SU rates, health state utility, and risk reduction of anaphylaxis. With health state utility sensitivity analyses, the ceiling value-based cost (willingness-to-pay threshold $100 000/QALY) was between $1568 and $6568 for EPIT and between $1235 and $5235 for POIT. If high rates of SU to peanut can be achieved in longer-term models, EPIT and POIT could produce savings in terms of both cost and QALY.

CONCLUSIONS AND RELEVANCE

In this simulated analysis, findings showed that EPIT and POIT may be cost-effective under some assumptions. Further research is needed to understand the degree of health state utility improvement associated with each therapy, degree of protection against anaphylaxis, and rates of SU.

A 10-year review found increasing incidence trends of emergency egg allergy reactions and food-induced anaphylaxis in children

AIM

International reports have suggested that food allergies and food-induced anaphylaxis have increased in children. We investigated the incidence of emergency food reactions over a 10-year period.

METHODS

This study retrospectively reviewed the medical records of children presenting to Umeå University hospital, Sweden, with an emergency food reaction from January 1, 2006 to December 31, 2015. Cases were identified using discharge codes for allergies and anaphylaxis. Anaphylaxis cases were included if they fulfilled the international criteria.

RESULTS

We found emergency food allergy reactions in 519 children (58% boys) from 2006-2015 at a median age of 1.3 years. One-third were hospitalised (32%) including 71/99 cases of anaphylaxis. Milk and eggs were the most commonly identified triggers. Emergency reactions to eggs increased during the study period with a Spearman rank correlation coefficient of 0.770 (p < 0.01) and the figures for anaphylaxis were 0.745 (p = 0.013). The incidence of food-induced anaphylaxis increased and was 30 per 100 000 person-years for the study period.

CONCLUSION

Most of the emergency reactions, treated by secondary care paediatricians and emergency physicians, were to milk and eggs. Allergic reactions to eggs increased from 2006 to 2015, as did food-related anaphylaxis.

Myths, facts and controversies in the diagnosis and management of anaphylaxis

Anaphylaxis is a serious systemic allergic reaction that is rapid in onset and may cause death. Despite numerous national and international guidelines and consensus statements, common misconceptions still persist in terms of diagnosis and appropriate management, both among healthcare professionals and patient/carers. We address some of these misconceptions and highlight the optimal approach for patients who experience potentially life-threatening allergic reactions.

Association of Fatality Risk With Value-Based Drug Pricing of Epinephrine Autoinjectors for Children With Peanut Allergy: A Cost-effectiveness Analysis

IMPORTANCE

The high cost of self-injectable epinephrine autoinjectors may represent a barrier to community anaphylaxis management. Value-based pricing can provide a benchmark for rational epinephrine autoinjector costs.

OBJECTIVE

To define value-based pricing of community epinephrine autoinjectors.

DESIGN, SETTING, AND PARTICIPANTS

In an economic evaluation study using a cost-effectiveness birth cohort model over an extended 80-year time horizon, Markov simulations of children with peanut allergy evaluated cost ceilings for value-based epinephrine prices in peanut allergy. Simulation inputs included all-cause age-adjusted mortality (2013 US life tables), 2013 published food allergy fatality rates, 2017 rates of autoinjector device carriage, and 2016 published market costs of self-injectable epinephrine. All costs were expressed in 2018 US dollars and discounted at 3% per annum.

EXPOSURES

Cohorts of children with peanut allergy prescribed epinephrine autoinjectors were compared with those not receiving personal epinephrine prescriptions. Children without epinephrine autoinjectors assumed 10-fold to 100-fold fatality risk increases. Costs were evaluated from a societal perspective.

MAIN OUTCOMES AND MEASURES

Fatality risk, quality-adjusted life-years, and incremental cost-effectiveness ratio.

RESULTS

A total of 100 000 simulated infants with peanut allergy entered each strategy, with two-thirds of the group receiving annual personal epinephrine prescriptions and using those devices appropriately when indicated. Over the time horizon, the cost of anaphylaxis preparedness and treatment in those with personal epinephrine devices was $25 478 (95% CI, $25 399-$25 557) compared with $654 (95% CI, $645-$663) for those without personal epinephrine, resulting in an average food allergy fatality of 0.00056 (95% CI, 0.000414-0.000706) per patient prescribed self-injectable epinephrine and 0.00148 (95% CI, 0.001242-0.001718) in those not prescribed self-injectable epinephrine. The value-based price (incremental cost-effectiveness ratio, $100 000 per quality-adjusted life-year) for personal epinephrine based on 10-fold fatality risk difference was $24. At a market cost of $715 per twin pack, the autoinjector incremental cost-effectiveness ratio was $2 742 697 per quality-adjusted life-year. If a hypothetical fatality risk protection from personal epinephrine was modeled at 100-fold, the value-based price ceiling for a personal autoinjector was $264.

CONCLUSIONS AND RELEVANCE

In a simulation of children with peanut allergy, a value-based epinephrine cost has a ceiling of $24 for a personal autoinjector, even at an exaggerated fatality risk.

The health and economic outcomes of early egg introduction strategies

BACKGROUND

Studies suggest early egg introduction (EEI) in the first year of life is associated with reduced risk of developing egg allergy. No US recommendations exist regarding optimally implementing EEI.

METHODS

Using simulation and Markov modelling over a 20-year horizon, we explored optimal EEI strategies applied to US, European and Canadian populations, comparing screening of high-risk infants (skin prick testing [SPT] or serum-specific IgE[sIgE]) before introducing cooked egg at 6 months of life vs egg introduction at home, without screening, for all infants.

RESULTS

A no-screen approach dominated egg SPT screening of high-risk infants with early-onset eczema. Base model per-patient incremental costs of SPT were $6865 US dollars (USD), 6801 euros and $10 610 Canadian dollars (CAD). For egg sIgE screening in primary care settings, base model incremental costs were $16 722 USD, 18 072 euros and $28 193 CAD. As the simulation concluded 2.5% were egg allergic without screening vs 9.5%, 12% and 21.4% of children undergoing SPT, delayed introduction or sIgE screening. Incremental societal costs from screening reached $2 009 351 175 USD for SPT and $4 894 445 790 USD for sIgE testing. In sensitivity analyses, if the risk of reaction with initial egg ingestion was ≥22.5%, SPT before EEI became a preferred strategy. A no-screen approach dominated both EEI of raw pasteurized egg and delayed cooked egg introduction approaches.

CONCLUSIONS

Assuming initial reaction rates < 22.5%, a no-screening EEI cooked egg approach has superior health and economic benefits in terms of number of egg allergy cases prevented and total healthcare costs vs screening testing.

The Epidemiology of Anaphylaxis

Anaphylaxis is a dramatic expression of systemic allergy. The lifetime prevalence of anaphylaxis is currently estimated at 0.05-2 % in the USA and ~3 % in Europe. Several population-specific studies have noted a rise in the incidence, particularly in the hospitalizations and ER visits due to anaphylaxis. The variable signs and symptoms that constitute the diagnostic criteria for anaphylaxis, the differences in diagnostic algorithms, and the limitations in the current coding systems have made summarizing epidemiologic data and comparing study results challenging. Nevertheless, across all studies, the most common triggers continue to be medications, food, and venom. Various risk factors for more severe reactions generally include older age, history of asthma, and having more comorbid diseases. Interesting seasonal, geographic, and latitude differences have been observed in anaphylaxis prevalence and incidence rates, suggesting a possible role of vitamin D and sun exposure in modifying anaphylaxis risk. While the incidence and prevalence of anaphylaxis appear to be increasing in certain populations, the overall fatality rate remains relatively low.

Anaphylaxis in the 21st century: phenotypes, endotypes, and biomarkers

Anaphylaxis is the most serious of all allergic reactions and can be fatal. The diagnosis is frequently delayed, and misdiagnosis often occurs with asthma or urticaria. Biomarkers such as tryptase are not routinely checked, and appropriate treatment with epinephrine is not administered in a majority of cases, increasing the risk of poor outcomes. The objective of this review is to provide a better understanding of the pathophysiology of anaphylaxis with a description of phenotypes, endotypes, and biomarkers available in both the clinical and research settings. Expanding knowledge with regard to the presentation, causes, and triggers for anaphylaxis among health care providers will improve its diagnosis and management, increase patient safety, and decrease morbidity and mortality.

Food-Induced Anaphylaxis: an Update

PURPOSE OF REVIEW

This review aims to provide an update of recent advances in the epidemiology, clinical features and diagnosis, and management of food-induced anaphylaxis (FIA).

RECENT FINDINGS

Food allergy prevalence and FIA rates continue to rise, but FIA fatalities are stable. Basophil and mast cell activation tests promise more accurate identification of food triggers. Oral, sublingual, and epicutaneous immunotherapy can desensitize a significant portion of subjects. Epinephrine use for FIA remains sub-optimal. As the burden of food allergy continues to increase, it appears that the corresponding increase in research focused on this epidemic is beginning to bear fruit. The stable number of FIA fatalities in the face of an ongoing epidemic indicates lives have already been saved. The emergence of new diagnostic tests and interventional therapies may transform the management of FIA in the coming years.

Fatal Anaphylaxis: Mortality Rate and Risk Factors

Up to 5% of the US population has suffered anaphylaxis. Fatal outcome is rare, such that even for people with known venom or food allergy, fatal anaphylaxis constitutes less than 1% of total mortality risk. The incidence of fatal anaphylaxis has not increased in line with hospital admissions for anaphylaxis. Fatal drug anaphylaxis may be increasing, but rates of fatal anaphylaxis to venom and food are stable. Risk factors for fatal anaphylaxis vary according to cause. For fatal drug anaphylaxis, previous cardiovascular morbidity and older age are risk factors, with beta-lactam antibiotics, general anesthetic agents, and radiocontrast injections the commonest triggers. Fatal food anaphylaxis most commonly occurs during the second and third decades. Delayed epinephrine administration is a risk factor; common triggers are nuts, seafood, and in children, milk. For fatal venom anaphylaxis, risk factors include middle age, male sex, white race, cardiovascular disease, and possibly mastocytosis; insect triggers vary by region. Upright posture is a feature of fatal anaphylaxis to both food and venom. The rarity of fatal anaphylaxis and the significant quality of life impact of allergic conditions suggest that quality of life impairment should be a key consideration when making treatment decisions in patients at risk for anaphylaxis.

BSACI guideline for the diagnosis and management of peanut and tree nut allergy

Peanut nut and tree nut allergy are characterised by IgE mediated reactions to nut proteins. Nut allergy is a global disease. Limited epidemiological data suggest varying prevalence in different geographical areas. Primary nut allergy affects over 2% of children and 0.5% of adults in the UK. Infants with severe eczema and/or egg allergy have a higher risk of peanut allergy. Primary nut allergy presents most commonly in the first five years of life, often after the first known ingestion with typical rapid onset IgE-mediated symptoms. The clinical diagnosis of primary nut allergy can be made by the combination of a typical clinical presentation and evidence of nut specifc IgE shown by a positive skin prick test (SPT) or specific IgE (sIgE) test. Pollen food syndrome is a distinct disorder, usually mild, with oral/pharyngeal symptoms, in the context of hay fever or pollen sensitisation, which can be triggered by nuts. It can usually be distinguish clinically from primary nut allergy. The magnitude of a SPT or sIgE relates to the probability of clinical allergy, but does not relate to clinical severity. SPT of ≥ 8 mm or sIgE ≥ 15 KU/L to peanut is highly predictive of clinical allergy. Cut off values are not available for tree nuts. Test results must be interpreted in the context of the clinical history. Diagnostic food challenges are usually not necessary but may be used to confirm or refute a conflicting history and test result. As nut allergy is likely to be a long-lived disease, nut avoidance advice is the cornerstone of management. Patients should be provided with a comprehensive management plan including avoidance advice, patient specific emergency medication and an emergency treatment plan and training in administration of emergency medication. Regular re-training is required.

Anaphylaxis to foods in a population of adolescents: incidence, characteristics and associated risks

BACKGROUND

Information about severe reactions to foods in adolescence is limited.

OBJECTIVE

To describe reactions to foods, including anaphylaxis, with regard to incidence, characteristics and associated risks, among 16-year-olds (adolescents) in a large, population-based birth cohort.

METHODS

Parent-reported questionnaire data from ages 2-3 months, and 1, 2 and 16 years were used (N = 3153). Anaphylaxis at age 16 years was defined per NIAID/FAAN criteria. Immunoglobulin E (IgE) antibodies to 14 common food and inhalant allergens were analysed at ages 4 (n = 2283) and 16 years (n = 2510). Among adolescents with food-related symptoms (FRS) and for whom blood was available (n = 221), 25 additional food allergen extracts or allergen components were analysed. Associations between reactions to foods, and sensitization and allergic multimorbidity were investigated.

RESULTS

In the 12 months prior to the 16-year assessment, 8.5% of adolescents had FRS. This included 0.8% (n = 24) adolescents who were classified as having anaphylaxis, yielding an incidence rate of 761/100 000 person-years. One-third of adolescents accessed health care during anaphylaxis. Allergic multimorbidity in infancy, as well as sensitization to foods and airborne allergens at age 4 years, was associated with an increased risk for FRS in adolescence. Peanuts and tree nuts were the most common culprit foods for anaphylaxis, and fruits and vegetables for non-anaphylactic reactions. Adolescents with anaphylaxis were significantly more likely to be sensitized to storage proteins (Ara h 2, Cor a 9, Cor a 14) and to be polysensitized to foods (P < 0.001 vs. non-anaphylactic reactions).

CONCLUSIONS AND CLINICAL RELEVANCE

The incidence of food-induced anaphylaxis during adolescence in our population-based birth cohort is higher than previously reported. Adolescents with anaphylaxis differ from adolescents with non-anaphylactic FRS with regard to culprit foods and sensitization. Adolescents with previous anaphylaxis are likely to be polysensitized to foods, particularly tree nut and peanut storage proteins, and which warrants consideration at follow-up.

Self-reported adverse food reactions and anaphylaxis in the SchoolNuts study: A population-based study of adolescents

BACKGROUND

Adolescents are at the highest risk of death from anaphylaxis, yet few population-based studies have described the frequencies and risk factors for allergic reactions caused by accidental allergen ingestion in this group.

METHODS

We describe the prevalence, frequency, and associated risk factors for recent adverse food reactions in 10- to 14-year-olds in Melbourne, Australia, recruited from a stratified, random, population-based sample of schools (SchoolNuts, n = 9663; 48% response rate). Self-reported food allergy and adverse reaction details, including anaphylaxis, were identified by using a student questionnaire over the past year.

RESULTS

Of 547 students with possible IgE-mediated food allergy, 243 (44.4%; 95% CI, 40.3% to 48.7%) reported a reaction to a food. Fifty-three (9.7%; 95% CI, 7.2% to 12.2%) students reported 93 anaphylaxis episodes. Peanut and tree nuts were the most common food triggers. Among students with current IgE-mediated food allergy, those with resolved or current asthma (adjusted odds ratio [aOR], 1.9 [95% CI, 1.1-1.3] and 1.7 [95% CI, 1.1-2.6]) and those with more than 2 food allergies (aOR, 1.9 [95% CI, 1.1-3.1]) were at greatest risk of any adverse food reaction, and those with nut allergy were most at risk of severe reactions (aOR, 2.9 [95% CI, 1.1-4.4]). Resolved or current asthma was not associated with increased risk of severe reactions (aOR, 0.8 [95% CI, 0.3-2.2] and 1.6 [95% CI, 0.7-3.7]).

CONCLUSIONS

Adolescents with food allergy are frequently exposed to food allergens. Those with asthma and more than 2 food allergies were at the greatest risk for adverse food reactions. Those with nut allergies were most at risk of severe reactions.

Epidemiology of severe anaphylaxis: can we use population-based data to understand anaphylaxis?

PURPOSE OF REVIEW

The observed increase in incidence of allergic disease in many regions over the past 3 decades has intensified interest in understanding the epidemiology of severe allergic reactions. We discuss the issues in collecting and interpreting these data and highlight current deficiencies in the current methods of data gathering.

RECENT FINDINGS

Anaphylaxis, as measured by hospital admission rates, is not uncommon and has increased in the United Kingdom, the United States, Canada, and Australia over the last 10-20 years. All large datasets are hampered by a large proportion of uncoded, 'unspecified' causes of anaphylaxis. Fatal anaphylaxis remains a rare event, but appears to be increasing for medication in Australia, Canada, and the United States. The rate of fatal food anaphylaxis is stable in the United Kingdom and the United States, but has increased in Australia. The age distribution for fatal food anaphylaxis is different to other causes, with data suggesting an age-related predisposition to fatal outcomes in teenagers and adults to the fourth decade of life.

SUMMARY

The increasing rates of food and medication allergy (the latter exacerbated by an ageing population) has significant implications for future fatality trends. An improved ability to accurately gather and analyse population-level anaphylaxis data in a harmonized fashion is required, so as to ultimately minimize risk and improve management.

Factors associated with epinephrine administration for anaphylaxis in children before arrival to the emergency department

BACKGROUND

Epinephrine is the first-line treatment for anaphylaxis but may be underused by patients and medical personnel.

OBJECTIVE

To evaluate factors associated with anaphylaxis management before arrival at the emergency department (ED) or urgent care center (UCC).

METHODS

We performed a retrospective review of electronic medical records for all patients aged 0 to 25 years presenting with anaphylaxis to the ED or UCC at a pediatric academic referral center during 2009 to 2013.

RESULTS

A total of 408 patients (mean age, 7.25 years; 62% male) were included for analysis. Only 148 patients (36.3%) received epinephrine before arrival at the ED or UCC. Reactions occurring at home (n = 36/114) were less likely to be treated with epinephrine compared with reactions occurring at school (n = 30/49) (odds ratio [OR], 0.29; 95% confidence interval [CI], 0.15-0.59). The odds of receiving epinephrine before arrival at the ED or UCC were significantly lower with a 2-organ system (OR, 0.50; 95% CI, 0.30-0.85) or 3-organ system (OR, 0.41; 95% CI, 0.21-0.81) presentation compared with 1-organ system involvement. Foods (342 [83.8%]) were the most commonly reported provoking trigger. Patients who did not receive epinephrine before arrival at the ED or UCC were significantly less likely to be discharged to home (OR, 0.56; 95% CI, 0.37-0.86; P = .01).

CONCLUSION

This study identifies factors associated with prehospital management of anaphylaxis for children, which highlight that epinephrine administration may be occurring with considerable delay. Increased awareness and education of caregivers, patients, and medical professionals are necessary to provide optimal management.

Oral immunotherapy for food allergy: A Spanish guideline. Immunotherapy egg and milk Spanish guide (items guide). Part I: Cow milk and egg oral immunotherapy: Introduction, methodology, rationale, current state, indications contraindications and oral immunotherapy build-up phase

INTRODUCTION

Cow's milk and egg are the most frequent causes of food allergy in the first years of life. Treatments such as oral immunotherapy (OIT) have been investigated as an alternative to avoidance diets. No clinical practice guides on the management of OIT with milk and egg are currently available.

OBJECTIVES

To develop a clinical guide on OIT based on the available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published in the period between 1984 and June 2016, Doctoral Theses published in Spain, and summaries of communications at congresses (SEAIC, SEICAP, EAACI, AAAAI), with evaluation of the opinion consensus established by a group of experts pertaining to the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations have been established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of suffering adverse reactions.

CONCLUSIONS

A clinical practice guide is presented for the management of OIT with milk and egg, based on the opinion consensus of Spanish experts.

Basophils and mast cells are crucial for reactions due to epicutaneous sensitization to ovalbumin

The prevalence of food allergies worldwide has increased recently. Epicutaneous sensitization to antigen could be a method to study food allergy. To clarify the mechanisms of food allergy, we established a mouse model of epicutaneous sensitization using ovalbumin (OVA). BALB/c mice were sensitized by three-time application of OVA to tape-stripped skin (1-week sensitization at 2-week intervals) and oral challenge of OVA undertaken. Rectal temperature was monitored. Blood and tissue (skin and jejunum) of challenged mice were taken. Numbers of mast cells (MCs) and basophils were counted. Serum and/or tissue levels of OVA -specific IgE and IgG antibodies and several cytokines were measured using enzyme-linked immunoassay kits. MC and basophil depletion experiments were undertaken. In OVA/epicutaneous-sensitized and orally challenged mice, systemic anaphylaxis (as evidenced by reduced rectal temperature) was observed. Levels of OVA-specific IgE and IgG antibodies were increased in these mice, as were increased number of MCs and basophils. Serum levels of MC protease 1 were increased significantly. Basophil and MC depletion experiments revealed that they both participate in reactions. Increased production of thymic stromal lymphopoietin (TSLP) at skin sites of OVA sensitization was noted. We speculate that TSLP produced from epidermal cells during antigen sensitization can enable basophils to promote a T helper (Th)2 immune reaction, leading to and systemic anaphylaxis by antigen-specific IgE-bearing MCs. This TSLP-basophils-MC axis could be a novel therapeutic target against food allergy.

Prevalence of Immediate-Type Food Allergy in Korean Schoolchildren in 2015: A Nationwide, Population-based Study

PURPOSE

This study aimed to determine the prevalence of immediate-type food allergy (FA) among schoolchildren in Korea.

METHODS

A nationwide, cross-sectional study was performed in September 2015. A stratified random sample of 50,000 participants was selected from children and adolescents aged 6-7 years (n=17,500), 9-10 years (n=17,500), 12-13 years (n=7,500), and 15-16 years (n=7,500). Parents were asked to complete a questionnaire on the detailed history of immediate-type FA.

RESULTS

A total of 32,001 (64.0%) responded to the questionnaire survey, and 29,842 children (59.7%) were analyzed after adjusting for missing data. The number of the cases in each age group was 9,671 (6-7 years), 9,756 (9-10 years), 5,169 (12-13 years), and 5,246 (15-16 years). The prevalence of lifetime perceived FA was 15.82%. The prevalence of current immediate-type FA was 4.06% in total, with 3.15% in 6- to 7-year-olds, 4.51% in 9- to 10-year-olds, 4.01% in 12- to 13-year-olds, and 4.49% in 15- to 16-year-olds. Among individual food items, peanut (0.22%) was the most frequent causative food, followed by hen's egg (0.21%), cow's milk (0.18%), and buckwheat (0.13%). Among the food groups, fruits (1.41%), crustaceans (0.84%), tree nuts (0.32%), and fish (0.32%) were the most common offending foods. The prevalence of food-induced anaphylaxis was 0.97%. The most frequent causative food of anaphylaxis was peanut (0.08%), followed by cow's milk (0.07%), buckwheat (0.06%), and hen's egg (0.06%), while fruits (0.28%), crustaceans (0.18%), tree nuts (0.12%), and fish (0.09%) were the most commonly responsible food groups.

CONCLUSIONS

The prevalence of current immediate-type FA and food-induced anaphylaxis in Korean schoolchildren in 2015 was 4.06% and 0.97%, respectively. Peanuts, cow's milk, hen's egg, fruits, crustaceans, and tree nuts are common allergens.

Can we identify patients at risk of life-threatening allergic reactions to food?

Anaphylaxis has been defined as a 'severe, life-threatening generalized or systemic hypersensitivity reaction'. However, data indicate that the vast majority of food-triggered anaphylactic reactions are not life-threatening. Nonetheless, severe life-threatening reactions do occur and are unpredictable. We discuss the concepts surrounding perceptions of severe, life-threatening allergic reactions to food by different stakeholders, with particular reference to the inclusion of clinical severity as a factor in allergy and allergen risk management. We review the evidence regarding factors that might be used to identify those at most risk of severe allergic reactions to food, and the consequences of misinformation in this regard. For example, a significant proportion of food-allergic children also have asthma, yet almost none will experience a fatal food-allergic reaction; asthma is not, in itself, a strong predictor for fatal anaphylaxis. The relationship between dose of allergen exposure and symptom severity is unclear. While dose appears to be a risk factor in at least a subgroup of patients, studies report that individuals with prior anaphylaxis do not have a lower eliciting dose than those reporting previous mild reactions. It is therefore important to consider severity and sensitivity as separate factors, as a highly sensitive individual will not necessarily experience severe symptoms during an allergic reaction. We identify the knowledge gaps that need to be addressed to improve our ability to better identify those most at risk of severe food-induced allergic reactions.

Patient quality of life following induction of oral immunotherapy for food allergy

BACKGROUND

Patient quality of life improves following successful completion of oral immunotherapy (OIT), but the process itself might have undesirable effects. We aimed to evaluate patient quality of life following OIT initial induction.

METHODS

The Hebrew version of the Food Allergy Quality of Life Questionnaire-Parental Form (FAQLQ-PF) was validated and administered to the parents of children following the first week of OIT for food allergy (n = 119). Patient demographics and clinical history as well as the course of initial induction week were reviewed.

RESULTS

Pre-OIT severity of food allergy, defined as severity of reactions due to accidental exposure to the allergenic food (anaphylactic reactions, p = 0.017; epinephrine use, p = 0.049; emergency room referrals p = 0.003; and hospital admissions, p = 0.015) and a lower number of tolerated doses during initial induction, reflective of a lower maximal tolerated dose for the different allergens (p = 0.011) were associated with worse total FAQLQ-PF scores. The number of tolerated doses during induction and pre-OIT emergency room referrals remained significantly associated with worse total score of the FAQLQ-PF on multivariate analysis (p = 0.016 and p = 0.005, respectively). The correlation between the number of tolerated doses and quality of life scores was moderate-strong primarily in children aged 6-12 years (Total score, r = -0.41, p = 0.001; Emotional Impact r = -0.42, p = 0.001; Food Anxiety, r = -0.38, p = 0.002; Social and Dietary Limitations, r = -0.33, p = 0.009).

CONCLUSIONS

Pre-OIT reaction severity affects quality of life in both preschool and school-aged food-allergic children. In contrast, a lower maximal tolerated dose during OIT induction is associated with worse indices of quality of life primarily in children aged 6-12 years.