The Risk of Recurrent Anaphylaxis

"Frequency of fatal and recurrent anaphylaxis due to COW'S milk: A systematic review and meta-analysis of observational studies"

Cow's milk allergy can result in anaphylactic reactions. The estimated prevalence of cow's milk allergy in developed countries ranges from 0.5% to 3% at age 1 year. Our objective was to perform a systematic review and, if possible, a meta-analysis to assess the frequency of fatal and recurrent anaphylaxis induced by cow's milk. We searched PubMed/MEDLINE, EMBASE, and the Web of Science for studies that had assessed fatal and recurrent anaphylaxis induced by cow's milk for the population of a country or at least an administrative region. Our review included cohort, cross-sectional, and registry studies that had assessed the incidence or prevalence of recurrent anaphylaxis or the incidence of fatal anaphylaxis due to cow's milk. The pooled prevalence of recurrence (PR) for at least an episode of anaphylaxis was 26.98% (3.85-189.1). Teymourpour et al (Iran) reported the highest PR (53.10%); the two studies with the lowest PR were from France (5.2 and 0.42, respectively) (p < .01). Nine studies on fatal anaphylaxis were selected (41 deaths) and found to be highly heterogeneous (I2  = 75.9%). Levy et al and Bassagio et al reported the highest incidence rate (IR 0.15 and 0.6 deaths per million persons-year). The PR of anaphylaxis was approximately one quarter of patients with anaphylaxis due to cow's milk, while deaths from anaphylaxis caused by cow's milk were very rare, although some studies report rates as high as 15 times the lowest IR.

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.

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.

Tree Nut-Induced Anaphylaxis in Canadian Emergency Departments: Rate, Clinical Characteristics and Management

BACKGROUND

Data are sparce regarding tree nut-induced anaphylaxis (TNA).

OBJECTIVE

We aimed to characterize rate, clinical characteristics, and management of TNA in children (0-17 years old) across Canada, and assess factors associated with severe reactions and epinephrine use.

METHODS

Between April 2011 and May 2020, data were collected on children presenting to five emergency departments (EDs) in Canada. Multivariate logistic analysis was used to evaluate factors associated with severe reactions (stridor, cyanosis, circulatory collapse, or hypoxia) and epinephrine use.

RESULTS

Among 3096 cases of anaphylaxis, 540 (17%) were induced by tree nut. The median age was 5.2 years [Interquartile range (IQR): 2.5-9.5] and 65.4% were males. Among all reactions, 7.0% were severe. The major tree nuts accounting for anaphylaxis were cashew (32.8%), hazelnut (20.0%) and walnut (11.5%). Cashew-induced anaphylaxis was more common in British Columbia [14.0% difference (95% CI, 1.6%-27.6%)] versus Ontario and Quebec, whereas pistachio-induced anaphylaxis was more common in Ontario and Quebec [6.3% difference (95% CI, 0.5%-12.2%)]. Pre-hospital and ED intramuscular (IM) epinephrine administration was documented in only 35.2% and 52.4% of cases, respectively. Severe reactions were more likely among males [adjusted Odds Ratio (aOR) 1.05 (95% CI, 1.01-1.10)] older children [aOR 1.00 (95% CI, 1.00-1.01)], and in reactions triggered by macadamia [aOR 1.27 (95% CI, 1.03-1.57)].

CONCLUSION

Different TNA patterns in Canada may be due to differences in lifestyle (higher prevalence of Asian ethnicity in British Columbia versus Arabic ethnicity in Ontario and Quebec). IM epinephrine underutilization urges for EAI stocking in schools and restaurants, patient education, and consistent policies across Canada.

Economic burden of food allergy in Canada: Estimating costs and identifying determinants

BACKGROUND

Limited data exist on the economic burden of food allergy (FA).

OBJECTIVE

To assess FA-related direct (healthcare and out-of-pocket) and indirect (lost productivity) costs and their determinants in Canadian children and adults self-reporting FA.

METHODS

FA-individuals self-reporting a convincing history or physician diagnosis were recruited through FA registries, an anaphylaxis registry, and advocacy associations, and electronically surveyed regarding FA-related healthcare use, out-of-pocket expenditures, and time lost from paid and unpaid labor. Direct and indirect costs (2020 Canadian dollars [CAD]) were stratified on severe reaction vs mild, moderate or no reaction, and children vs adults; multivariate regressions assessed the association between costs and sociodemographic and disease characteristics.

RESULTS

Between May 2018 and July 2019, 2692 eligible individuals responded (2189 convincing history and 503 physician diagnosis only); 1020 experienced a severe reaction; 1752 were children. Per FA-individual, annual healthcare, out-of-pocket, and indirect costs were $1267, $2136, and $7950. Those with a severe reaction had higher healthcare and out-of-pocket costs than those with mild, moderate or no reaction. FA-children vs FA-adults had higher healthcare and out-of-pocket costs, and lower indirect costs. Multivariate results showed that lower age, a severe reaction ever, multiple FAs, and fair or poor general health were associated with higher healthcare and out-of-pocket costs. Higher age, lower household education and income, and fair or poor general health were associated with higher indirect costs.

CONCLUSION

The economic burden of FA in Canada is substantial, particularly for those with a severe reaction ever, multiple FAs, and fair or poor general health. It is crucial that those most adversely affected are allocated appropriate resources to support disease management.

Evaluation of anaphylaxis recurrence and adrenaline autoinjector use in childhood

Introduction: Limited data are available on recurrent anaphylaxis in childhood. Delayed adrenaline administration is the major cause of deaths due to anaphylaxis. As well as prescribing the adrenaline autoinjector (AAI), it is important to make sure that the patient carries the device at all times and uses it correctly for the appropriate indication. Objective: The aim of our study was to evaluate the recurrence of anaphylaxis and AAI use in childhood. Methods: Pediatric patients who were evaluated for anaphylaxis and prescribed AAI between January 2015 and December 2018, in the pediatric allergy and immunology clinic of our hospital were screened retrospectively. A telephone-based survey was conducted with the parents of the patients to investigate the recurrence of anaphylaxis in patients and the use of AAI by their parents for the management of anaphylaxis. Results: A total of 148 patients (64.9% boys) were prescribed an AAI for anaphylaxis. The telephone survey could be conducted with 111 parents (75%) with an AAI prescription. Of these patients, 23.4% (n = 26) of the parents reported that their children experienced recurrent episodes of anaphylaxis. In the recurrent anaphylaxis cases, the triggers were foods in 77%, venoms in 11.5%, drugs in 3.8%, and idiopathic anaphylaxis in 7.7% of the patients. AAI use at the time of anaphylaxis was reported by 42.3% of the parents. The reasons cited by the parents for not using AAI during an episode of anaphylaxis included the preference to have adrenaline administered at a health care facility because of its proximity (60%), fear of using the device (13.3%), hesitation (6.7%), not having the device with them (13.3%), and unavailability of the device (6.7%). Conclusion: Educating the patients and families about the importance of using AAI is crucial, and training on how to use the device should be repeated at each clinic visit and every opportunity.

Emergency department revisits and rehospitalizations among infants and toddlers for acute allergic reactions

Background and Objective: Allergic reactions, including anaphylaxis, are rising among children. Little is known about health care utilization among infants and toddlers. Our objective was to characterize health care utilization and charges for acute allergic reactions (AAR). Methods: We conducted a retrospective cohort study of trends in emergency department (ED) visits and revisits, hospitalizations and rehospitalizations, and charges among infants and toddlers (ages < 3 years), with an index ED visit or hospitalization for AAR (including anaphylaxis). We used data from population-based multipayer data: State Emergency Department Databases and State Inpatient Databases from New York and Nebraska. Multivariable logistic regression was used to identify factors associated with ED revisits and rehospitalizations. Results: Between 2006 and 2015, infant and toddler ED visits for AAR increased from 27.8 per 10,000 population to 35.2 (P_trend < 0.001), whereas hospitalizations for AAR remained stable (P_trend = 0.11). In the one year after an index AAR visit, 5.1% of these patients had at least one AAR ED revisit and 5.9% had at least one AAR rehospitalization. Factors most strongly associated with AAR ED revisits included an index visit hospitalization and receipt of epinephrine. Total charges for AAR ED visits (2009-2015) and hospitalizations (2011-2015) were more than $29 million and $11 million, respectively. Total charges increased more than fourfold for both AAR ED revisits for AAR rehospitalizations during the study period. Conclusion: Infants and toddlers who presented with an AAR were at risk for ED revisits and rehospitalizations for AAR within the following year. The charges associated with these revisits were substantial and seemed to be increasing.

Community Use of Epinephrine for the Treatment of Anaphylaxis: A Review and Meta-Analysis

BACKGROUND

Community use of epinephrine for the treatment of anaphylaxis is low. Knowledge of rates of epinephrine use in the pre-hospital setting along with identification of barriers to its use will contribute to the development of policies and guidelines.

OBJECTIVES

A search was conducted on PubMed and Embase in April 2020. Our systematic review focused on 4 domains: (1) epinephrine use in the pre-hospital setting; (2) barriers to epinephrine use in the pre-hospital setting; (3) cost evaluation and cost-effectiveness of epinephrine use; and (4) programs and strategies to improve epinephrine use during anaphylaxis.

METHODS

Two meta-analyses with logit transformation were conducted to: (1) calculate the pooled estimate of the rate of epinephrine use in the pre-hospital setting among cases of anaphylaxis and (2) calculate the pooled estimate of the rate of biphasic reactions among all cases of anaphylaxis.

RESULTS

Epinephrine use in the pre-hospital setting was significantly higher for children compared with adults (20.98% [95% confidence interval (CI): 16.38%, 26.46%] vs 7.17% [95% CI: 2.71%, 17.63%], respectively, P = .0027). The pooled estimate of biphasic reactions among all anaphylaxis cases was 3.92% (95% CI: 2.88%, 5.32%). Our main findings indicate that pre-hospital use of epinephrine in anaphylaxis remains suboptimal. Major barriers to the use of epinephrine were identified as low prescription rates of epinephrine autoinjectors and lack of stock epinephrine in schools, which was determined to be cost-effective. Finally, in reviewing programs and strategies, numerous studies have engineered effective methods to promote adequate and timely use of epinephrine.

CONCLUSION

The main findings of our study demonstrated that across the globe, prompt epinephrine use in cases of anaphylaxis remains suboptimal. For practical recommendations, we would suggest considering stock epinephrine in schools and food courts to increase the use of epinephrine in the community. We recommend use of pamphlets in public areas (ie, malls, food courts, etc.) to assist in recognizing anaphylaxis and after that with prompt epinephrine administration, to avoid the rare risk of fatality in anaphylaxis cases.

Risk of peanut- and tree-nut-induced anaphylaxis during Halloween, Easter and other cultural holidays in Canadian children

BACKGROUND

It is not established whether the risk of anaphylaxis induced by peanuts or tree nuts in children increases at specific times of the year. We aimed to evaluate the risk of peanut-and tree-nut-induced anaphylaxis during certain cultural holidays in Canadian children.

METHODS

We collected data on confirmed pediatric cases of anaphylaxis presenting to emergency departments in 4 Canadian provinces as part of the Cross-Canada Anaphylaxis Registry. We assessed the mean number of cases per day and incidence rate ratio (IRR) of anaphylaxis induced by unknown nuts, peanuts and tree nuts presenting during each of 6 holidays (Halloween, Christmas, Easter, Diwali, Chinese New Year and Eid al-Adha) versus the rest of the year. We estimated IRRs and 95% confidence intervals (CIs) using Poisson regression.

RESULTS

Data were collected for 1390 pediatric cases of anaphylaxis between 2011 and 2020. Their median age was 5.4 years, and 864 (62.2%) of the children were boys. During Halloween and Easter, there were higher rates of anaphylaxis to unknown nuts (IRR 1.66, 95% CI 1.13-2.43 and IRR 1.71, 95% CI 1.21-2.42, respectively) and peanuts (IRR 1.86, 95% CI 1.12-3.11 and IRR 1.57, 95% CI 0.94-2.63, respectively) compared to the rest of the year. No increased risk of peanut- or tree-nut-induced anaphylaxis was observed during Christmas, Diwali, Chinese New Year or Eid al-Adha. Anaphylaxis induced by unknown nuts, peanuts and tree nuts was more likely in children aged 6 years or older than in younger children.

INTERPRETATION

We found an increased risk of anaphylaxis induced by unknown nuts and peanuts during Halloween and Easter among Canadian children. Educational tools are needed to increase awareness and vigilance in order to decrease the risk of anaphylaxis induced by peanuts and tree nuts in children during these holidays.

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.

Anaphylaxis-a 2020 practice parameter update, systematic review, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis

Anaphylaxis is an acute, potential life-threatening systemic allergic reaction that may have a wide range of clinical manifestations. Severe anaphylaxis and/or the need for repeated doses of epinephrine to treat anaphylaxis are risk factors for biphasic anaphylaxis. Antihistamines and/or glucocorticoids are not reliable interventions to prevent biphasic anaphylaxis, although evidence supports a role for antihistamine and/or glucocorticoid premedication in specific chemotherapy protocols and rush aeroallergen immunotherapy. Evidence is lacking to support the role of antihistamines and/or glucocorticoid routine premedication in patients receiving low- or iso-osmolar contrast material to prevent recurrent radiocontrast media anaphylaxis. Epinephrine is the first-line pharmacotherapy for uniphasic and/or biphasic anaphylaxis. After diagnosis and treatment of anaphylaxis, all patients should be kept under observation until symptoms have fully resolved. All patients with anaphylaxis should receive education on anaphylaxis and risk of recurrence, trigger avoidance, self-injectable epinephrine education, referral to an allergist, and be educated about thresholds for further care.

Commercial claims costs related to health care resource use associated with a diagnosis of peanut allergy

BACKGROUND

Peanut allergy (PA) affects approximately 1.6 million US children. The current standard of care is strict avoidance and prompt reaction treatment. Peanut allergy health care costs and health care resource utilization (HCRU) are poorly understood.

OBJECTIVE

To estimate PA health care costs and HCRU using a nationally representative commercial payer database.

METHODS

The IBM MarketScan Commercial Claims and Encounters Database was examined for PA diagnosis/reaction codes between January 2010 and October 2016 in patients 64 years of age or younger, with age cohort-matched controls. Outcomes were measured 12 months before and after the first claim date. Health care costs and HCRU were compared using Student's t tests and χ² tests.

RESULTS

Patients with a PA-related diagnostic code (n = 41,675) incurred almost double all-cause health care costs vs controls ($6436 vs $3493, P < .001), mainly from inpatient and outpatient medical costs ($5002 vs $2832, P < .001). More than one third of the PA group patients (36%) had a code indicative of an anaphylactic reaction during follow-up. Mean PA or reaction-related code costs per visit totaled $7921 for hospitalizations and $1115 for emergency department (ED) visits. Costs were 30% lower in patients with asthma codes without PA codes vs those with both codes ($5678 vs $8112, P < .001); all-cause ED costs were more than double in patients with atopic dermatitis codes with PA codes vs those without PA codes ($654 vs $308, P < .001).

CONCLUSION

National commercial payer claims data indicate a significant health care burden associated with a PA-related code, including over $6400/patient in annual all-cause costs and increased health care utilization.

Recurrent anaphylaxis in the United States: time of onset and risk factors

BACKGROUND

Studies have not yet examined the trends and risk factors of biphasic and recurrent anaphylaxis in the United States using International Classification of Diseases, tenth revision (ICD-10) CM codes. The goal of this study is to examine the trends of biphasic and recurrent anaphylaxis in all patient care settings (inpatient, outpatient, emergency department, and observation).

METHODS

We used the Clinformatics database from 2015 to 2017. Our main outcome measure was recurrent anaphylactic events occurring within 1 year after the initial event. We used Cox proportional hazards modeling to assess the factors associated with recurrent anaphylaxis and the Kaplan-Meier method to estimate time to recurrence.

RESULTS

There were a total of 19,039 patients with incident anaphylaxis in 2016 and, of these, 2017 had a recurrent anaphylaxis event in the 12-month period after the index date (10.6%). The most common trigger for recurrent anaphylaxis is venom followed by food allergens. Pediatric patients aged <18 years were more likely to develop recurrent anaphylaxis compared with patients aged 18 to 64 years (hazard ratio [HR], 1.53). Patients with allergic rhinitis and asthma were more likely to develop recurrent anaphylaxis compared to those without these comorbidities (HR, 1.15 and 1.27, respectively).

CONCLUSION

This is the first national study using ICD-10 CM codes looking at rates of biphasic and recurrent anaphylaxis in all patient care settings. Recurrent anaphylaxis is more common in the first 3 days after the initial event, in younger patients (<18 years), and in patients with allergic rhinitis and/or asthma. Physicians need to prescribe epinephrine auto-injectors and educate their patients about the risk of recurrence.

Anaphylaxis admissions in pediatric intensive care units: Follow-up and risk of recurrence

BACKGROUND

Data about the risk of anaphylaxis recurrence in children are lacking. We assessed anaphylaxis recurrence and medical follow-up in a cohort of children previously hospitalized in a French pediatric intensive care unit (PICU) for anaphylaxis.

METHODS

We conducted a telephone survey of 166 children (≤18 years) hospitalized from 2003 to 2013.

RESULTS

In all, 106 (64%) completed the survey (boys, 59%; mean age [SD]: 15.3 years [5.5]). The main index triggers were drugs (45%) and foods (37%). The mean duration follow-up was of 7.7 years (SD: 2.4). Thirty-eight (36%) children experienced 399 new allergic reactions during a follow-up period of 282 patient-years (incidence rate: 1.4/100 patients/y; 95% CI: 0.64-2.04). Twelve children experienced 19 anaphylaxis reactions including five requiring PICU admission (anaphylaxis recurrence rate: 0.20/100 patients/y; 95% CI non-calculable). Food was the trigger for 79% of recurrent reactions and drugs for 8%. The food trigger was previously known in 83%, the same as the index trigger in 69%. Overall, 1.5% of the recurrent reactions were treated with adrenaline injection and 8% an emergency hospital admission. Patients with recurrence had more likely a history of food allergy (P < 10^-4 ), asthma (P < 0.005), atopic dermatitis (P < 0.05) than those without. 31% of the 50 children with food allergy did not see an allergist, 23% had no adrenaline auto-injector, and 26% lacked a school individual healthcare plan.

CONCLUSIONS

Following a PICU admission for anaphylaxis, recurrence is high in children with food allergy compared with drug allergy. Allergic comorbidities increase the risk. Medical follow-up has to be improved for these at-risk children.

Evaluation of Prehospital Management in a Canadian Emergency Department Anaphylaxis Cohort

BACKGROUND

Studies assessing the use of antihistamines and corticosteroids for the treatment of anaphylaxis have not supported a conclusive effect.

OBJECTIVE

To assess prehospital management of anaphylaxis by measuring the effect of epinephrine use compared with antihistamines and corticosteroids on negative outcomes of anaphylaxis (intensive care unit/hospital ward admission, multiple doses of epinephrine in the emergency department [ED], and intravenous fluids given in the ED).

METHODS

The Cross-Canada Anaphylaxis Registry is a cohort study that enrolls anaphylaxis cases presenting to EDs in 5 Canadian provinces over a 6-year period. Participants were recruited prospectively and retrospectively and were excluded if the case did not meet the definition of anaphylaxis.

RESULTS

A total of 3498 cases of anaphylaxis, of which 80.3% were children, presented to 9 EDs across Canada. Prehospital treatment with epinephrine was administered in 31% of cases, whereas antihistamines and corticosteroids were used in 46% and 2% of cases, respectively. Admission to the intensive care unit/hospital ward was associated with prehospital treatment with corticosteroids (adjusted odds ratio, 2.84; 95% confidence interval [CI], 1.55, 6.97) while adjusting for severity, treatment with epinephrine and antihistamines, asthma, sex, and age. Prehospital treatment with epinephrine (adjusted odds ratio, 0.23; 95% CI, 0.14, 0.38) and antihistamines (adjusted odds ratio, 0.61; 95% CI, 0.44, 0.85) decreased the likelihood of receiving multiple doses of epinephrine in the ED, while adjusting for severity, treatment with corticosteroids, asthma, sex, and age.

CONCLUSIONS

Prompt epinephrine treatment is crucial. Use of antihistamines in conjunction with epinephrine may reduce the risk of uncontrolled reactions (administration of 2 or more doses of epinephrine in the ED), although our findings do not support the use of corticosteroids.

Use of epinephrine in emergency department depends on anaphylaxis severity in children

Despite multiple recommendations, intramuscular epinephrine is poorly prescribed in emergency department receiving pediatric anaphylaxis. To evaluate the role of severity symptoms on this use, we included all admissions for a diagnosis linked to possible allergy in the two pediatric emergency departments of our institution between January 2010 and December 2015. Selection and analysis were restricted to children under 18 years fulfilling Sampson's criteria for anaphylaxis. We retrospectively ranked these admissions with the Ring and Messmer anaphylaxis severity score and compared the use of epinephrine according to this classification. Among 422,483 admissions, 204 (0.05%) fulfilled the anaphylaxis criteria (170 (83.3%) grade II anaphylaxis, and 34 (16.7%) grade III; mean age 7.9 years). Previous allergy, anaphylaxis, and asthma were found in respectively 60.8%, 36.8%, and 35.1%. Food allergy was the main suspected causal trigger. Epinephrine was used in 32.7% (n = 65/199), before admission (11.4% (n = 23/201)) or in the emergency department (22.2% (n = 45/202)). Epinephrine was more frequently prescribed in grade III than in grade II anaphylaxis (84.8% vs 22.3%, p < 0.001; OR = 19.05 [7.05-54.10]). Upon discharge, epinephrine auto-injectors prescription and allergy referral were rare (31.7% and 44.2%).Conclusion: Pediatricians intuitively adapt their epinephrine use to the severity of the anaphylaxis and contribute to epinephrine underuse in pediatric anaphylaxis. What is known: • Intramuscular epinephrine is the recommended treatment for pediatric anaphylaxis. However, most of the European and North-American studies show a low prescription rate of epinephrine in both prehospital and pediatric emergency department management. • Reasons for such a low prescription rate are unknown. What is new: • This study confirms that intramuscular epinephrine is poorly prescribed in pediatric anaphylaxis (about one case among 10 before admission and one among 5 in pediatric emergency departments). • Despite recommendations, pediatricians intuitively adapt their prescription to the clinical severity of anaphylaxis, with a fourfold increase prescription in grade III compared to grade II anaphylaxis. This medical behavior ascertainment may be in part explained by the delay between the ED admission/management and the anaphylactic episode onset.

Risk factors for recurrent anaphylaxis-related emergency department visits in the United States

BACKGROUND

Anaphylaxis is a potentially life-threatening allergic reaction with a strong risk of recurrence.

OBJECTIVE

To assess risk factors associated with recurrent anaphylaxis-related emergency department (ED) visits within 1 year of an ED visit for anaphylaxis in a large observational cohort study.

METHODS

We used an administrative claims database to identify patients seen from 2008 through 2012 in the ED for anaphylaxis based on an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code algorithm. Patients with at least 2 years of continuous enrollment in a health plan were included. Multivariable logistic regression analysis was used to determine associations with recurrence of anaphylaxis within 1 year.

RESULTS

During the 5-year study period, 7,367 patients (median age, 42 years; <18 years old, 23.3%) met the inclusion criteria. The most common anaphylaxis trigger was unspecified (56.2%), followed by food (25.3%), medication (14.6%), and venom (3.9%). Overall, 3.0% of patients had an additional anaphylaxis-related ED visit within 1 year (3.61 episodes per 100 patient-years). On multivariable analysis, risk factors associated with anaphylaxis recurrence were food trigger (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.34-3.99), history of asthma (OR, 1.30; 95% CI, 1.13-1.51), and intensive care unit admission at the index anaphylaxis event (OR, 1.95; 95% CI, 1.41-2.69).

CONCLUSION

In this contemporary cohort study, history of asthma, food trigger, and greater index anaphylaxis severity, as measured by intensive care unit admission, were associated with a higher likelihood of a recurrent anaphylaxis-related ED visit within 1 year.

Food allergy and anaphylaxis

Anaphylaxis is a severe and potentially life-threatening allergic reaction. There are numerous potential causes, with food allergy being the leading cause in children and the focus of this review. Most reactions involve an IgE-mediated mechanism, although non-IgE-mediated and nonimmunologic reactions can occur. Various cofactors to be discussed can place certain individuals at an increased risk of severe or fatal anaphylaxis. The clinical manifestations of anaphylaxis are broad and may involve multiple body systems. Diagnosis of food-related anaphylaxis is primarily based on signs and symptoms and supported, wherever possible, by identification and confirmation of a culprit food allergen. First-line treatment of anaphylaxis is intramuscular administration of epinephrine. Long-term management is generally focused on strict allergen avoidance and more recently on food desensitization using immunotherapy. This review provides an overview of anaphylaxis with a specific focus on food allergy.

Knowledge of allergies and performance in epinephrine auto-injector use: a controlled intervention in preschool teachers

Epinephrine auto-injectors are used for first aid in anaphylactic emergencies by non-healthcare professionals, e.g., (pre-)school teachers. We developed an education session for preschool teachers addressing allergies, anaphylactic emergencies, and administering auto-injectors. We assessed their attitudes and knowledge in allergies and anaphylactic emergency by a questionnaire and monitored their practical performance in administering auto-injectors before the education session, directly after, and 4-12 weeks after the session. From 75 teachers giving their consent to participate, 81% had children with allergies under their supervision and 3% had already administered medication from an available rescue kit. The knowledge of triggers of allergies increased from 9 to 55% directly and to 33% 4-12 weeks after the session (both p < 0.001, compared to baseline). Directly after the session, the number of teachers who felt well-prepared for an anaphylactic emergency rose from 11 to 88%, which decreased to 79% 4-12 weeks thereafter (each p < 0.001). The number of auto-injector administrations without any drug-related problems increased from 3 to 35% directly after the session and shrunk to 16% 4-12 weeks afterwards (both p < 0.025).

CONCLUSION

A single education session substantially improved preschool teachers' attitudes and knowledge in allergies and anaphylactic emergencies. Additionally, their practical performance in auto-injector administration increased. What is Known: • Food allergies are increasing among children. • The knowledge about allergies and anaphylactic emergencies is poor. What is New: • The proportion of teachers who felt well-prepared for an anaphylactic emergency increased after a single education session. • The proportion of auto-injector administrations without any drug-related problems additionally increased due to an education session.

Contemporary issues in anaphylaxis and the evolution of epinephrine autoinjectors: What will the future bring?

BACKGROUND

Food allergy and anaphylaxis appear to be increasing in the United States, especially in young children, and preparedness is paramount to successful emergency management in the community. Although the treatment of choice for anaphylaxis is epinephrine delivered by autoinjection, some devices are challenged by less user-friendly designs or pose the risk of injury, especially in young patients. Human factors engineering has played a larger role in the development of more recent epinephrine autoinjector technologies and will continue to play a role in the evolution and future design of epinephrine autoinjectors.

OBJECTIVE

To discuss contemporary issues related to the identification and management of anaphylaxis, current and future epinephrine autoinjector design, and unmet needs for the treatment of special populations, namely, young children weighing less than 15 kg.

METHODS

The literature was reviewed and select articles retrieved to support expert clinical opinions on the need for improved recognition of anaphylaxis, epinephrine autoinjector design, and unmet needs in special populations.

RESULTS

Anaphylaxis may be underrecognized and poorly defined in infant- and toddler-aged children, current devices may not be adequate to safely treat these patients (ie, inappropriate needle length), and health care professionals may not be aware of these issues.

CONCLUSION

As epinephrine autoinjector technology continues to evolve, device characteristics that promote safe, user-friendly experiences and give clinicians and their patients confidence to successfully treat anaphylaxis during an emergency, without injury, will be favored.