Rate, triggers, severity and management of anaphylaxis in adults treated in a Canadian emergency department

Diagnosis and management of food allergy-induced constipation in young children-An EAACI position paper

The recognition of constipation as a possible non-Immunoglobulin E (IgE)-mediated allergic condition is challenging because functional constipation (unrelated to food allergies) is a common health problem with a reported worldwide prevalence rate of up to 32.2% in children. However, many studies in children report challenge proven cow's milk allergy and constipation as a primary symptom and have found that between 28% and 78% of children improve on a cow's milk elimination diet. Due to the paucity of data and a focus on IgE-mediated allergy, not all food allergy guidelines list constipation as a symptom of food allergy. Yet, it is included in all cow's milk allergy guidelines available in English language. The Exploring Non-IgE-Mediated Allergy (ENIGMA) Task Force (TF) of the European Academy for Allergy and Clinical Immunology (EAACI) considers in this paper constipation in the context of failure of standard treatment and discuss the role of food allergens as culprit in constipation in children. This position paper used the Delphi approach in reaching consensus on both diagnosis and management, as currently published data are insufficient to support a systematic review.

Prehospital and In-Hospital Treatment with Adrenaline and Related Prognosis in Anaphylaxis Patients

INTRODUCTION

Although intramuscular adrenaline is the recommended first-line treatment for anaphylaxis, not all patients receive this treatment. The consequences in daily clinical practice are sparsely described. This study aimed to investigate the treatment administered to anaphylactic patients and the related prognosis.

METHODS

A retrospective register-based study of patients with anaphylaxis referred to the allergy centre, Odense University Hospital (2019-2021). Each patient's medical records were reviewed for contacts with the emergency departments and the prehospital emergency medical service in the Region of Southern Denmark. The World Allergy Organization (WAO) grading system was used to assess the severity of prehospital and in-hospital anaphylaxis. Furthermore, the treatment administered to the patients was registered.

RESULTS

In total, 315 patients were included. The prehospital system had contact with 256 of these patients (two were released prehospitally following treatment and 12 patients had insufficient data to assess anaphylaxis). Of the remaining 242 patients, 115 had anaphylaxis prehospitally (WAO grades 3-5); 59% (67/115) received adrenaline. Among the 67 patients who received prehospital adrenaline, 9 patients (13.4%; 95% CI: 6.3-24.0%) still had anaphylaxis at arrival at the emergency department. Of the 48 patients that were not treated with prehospital adrenaline, 17 patients (35.5%; 95% CI: 22.1-50.5) had anaphylaxis at the arrival to the emergency department. Among the 127 patients without prehospital anaphylaxis (WAO grades 0-2), 22 patients (18.2%; 95% CI: 11.8-26.2%) who did not receive prehospital adrenaline had anaphylaxis at arrival to the emergency department, while none of the 6 patients treated prehospitally with adrenaline had anaphylaxis.

CONCLUSION

Omission of prehospital adrenaline in anaphylactic patients is associated with more severe anaphylactic symptoms at arrival to the hospital. Adrenaline treatment remains suboptimal since only half of the patients received prehospital adrenaline and only 1 out of 4 patients, with clinical signs of anaphylaxis, received adrenaline inside the hospital.

Dietary management of IgE and non-IgE-mediated food allergies in pediatric patients

Food allergies (FA) consist of both IgE and non-IgE-mediated entities, with varying phenotypes and overlapping and different considerations for each specific disease presentation. In general, all FAs place children at increased risk for inadequate nutritional intake and negative impacts on their nutritional status, as well as negative impacts on the quality of life for the entire family. To minimize these untoward effects, a multidisciplinary approach should be taken, including consultation and management with a dietitian trained in the varying presentations of FA. Families should be instructed on label reading as a first line of nutritional management. During a nutrition consultation, the age of the child, growth, and nutritional status should be considered. Food refusal should be assessed and addressed. Families should be educated on avoidance and appropriate substitutions. In the case of cow's milk allergy, a suitable specialized formula should be suggested if the infant is not breastfed or if breast milk supply is not sufficient. Other mammalian milk should be avoided and careful consideration should be given before plant-based milk is used in young children. Specific food allergies may differ in terms of advice provided on the level of avoidance required, whether precautionary advisory labels should be avoided, and if a maternal avoidance of the allergen during breastfeeding should be advised. The role of immunonutrition on overall health should be discussed.

Identifying Children at Risk of Growth and Nutrient Deficiencies in the Food Allergy Clinic

BACKGROUND

Food allergies affect growth in children by decreasing the availability of nutrients through decreased dietary intake, increased dietary needs, food-medication interactions, and psychosocial burden. Guidelines on food allergy management frequently recommend nutrition counseling and growth monitoring of children with food allergies.

OBJECTIVE

To provide clear guidance for clinicians to identify children with food allergies who are at nutritional risk and ensure prompt intervention.

METHODS

We provide a narrative review summarizing information from national and international guidelines, retrospective studies, population studies, review articles, case reports, and case series to identify those with food allergy at greatest nutritional risk, determine the impact of nutritional interventions on growth, and develop guidance for risk reduction in children with food allergies.

RESULTS

Children with food allergies are at increased risk of nutritional deficiencies and poor growth. Nutritional assessment and intervention can improve outcomes. Identifying poor growth is an important step in the nutrition assessment. Therefore, growth should be assessed at each allergy evaluation. Interventions to ensure adequate dietary intake for growth include appropriately prescribed elimination diets, breast-feeding support and assessment, supplemental formula, vitamin and/or mineral supplementation, appropriate milk substitutes, and timely introduction of nutrient-dense complementary foods. Access to foods of appropriate nutritional value is an ongoing concern.

CONCLUSION

Nutrition intervention or referral to registered dietitian nutritionists with additional training and/or experience in food allergy may result in improved growth and nutrition outcomes.

Epidemiology of anaphylaxis: is the trend still going up?

PURPOSE OF REVIEW

To understand the current global scale of anaphylaxis and identify possible strategies to increase the accuracy of epidemiological data.

RECENT FINDINGS

Anaphylaxis mortality and morbidity statistics may gain new perspectives with the global implementation of the ICD-11. Improving the quality of epidemiological data related to anaphylaxis should clarify some areas of uncertainty about risk factors, leading to better targeting of strategies to protect those patients at risk, and support decision-making to facilitate health care planning and implementation of public health measures to prevent anaphylaxis.

SUMMARY

The true rate of anaphylaxis is unknown due to a number of factors, such as misdiagnosis, miscoding and undernotification. Moreover, there is lack of information about anaphylaxis epidemiology in many countries. Difficulties on collecting accurate and comparable data should be acknowledged and anaphylaxis data can vary widely. Currently, most robust data are derived from hospitalization datasets and national mortality databases. Anaphylaxis accounts for up to 0.26% of overall hospital admissions. It is suggested that the number of hospital admissions for anaphylaxis is increasing in many countries, both with respect to all-causes of anaphylaxis and by trigger, but the mortality rate remains low. However, there are still great challenges in capturing quality anaphylaxis mortality and morbidity statistics. Better understanding of anaphylaxis trends should clarify some areas of uncertainty about risk factors and prospect effective prevention strategies. As the knowledge derived from populations is key information for more realistic decision-making, the construction of the new section addressed to anaphylaxis in the ICD-11 will allow the collection of more accurate epidemiological data to support high quality management of patients, and to better facilitate health care planning to implement public health measures, reduce the morbidity and mortality attributable to anaphylaxis.

Epinephrine treatment of food-induced and other cause anaphylaxis in United States and Canadian Emergency Departments: a systematic review and meta-analysis

INTRODUCTION

Studies from more than 10 years ago showed epinephrine treatment of food-induced anaphylaxis in the emergency department (ED) was unacceptably low. We investigated whether epinephrine treatment of food-induced and other cause anaphylaxis in United States and Canadian EDs has changed over time.

METHODS

Guided by a health sciences librarian, we performed a systematic search in Medline, Embase, and Web of Science on 11 January 2023. We included observational studies that reported epinephrine use to treat anaphylaxis in the ED. We stratified by anaphylaxis etiology (food-, venom-, medication-induced, or any cause). Associations between year and epinephrine use were tested using Spearman correlation and proportional meta-analysis.

RESULTS

Of 2458 records identified in our initial search, 40 met inclusion criteria. Of these, 14 examined food-induced, 4 venom-induced, 0 medication-induced, and 24 any cause anaphylaxis. For epinephrine treatment of food-induced anaphylaxis in the ED, among studies using similar definition of anaphylaxis, meta-analysis showed a pooled value of 20.7% (95% CI 17.8, 23.8) for studies performed >10 years ago and 45.1% (95% CI 38.4, 52.0) from those in the last 10 years. For anaphylaxis of any cause, there was no change over time, with a pooled value of 45.0% (95% CI 39.8, 50.3) over the last 10 years.

DISCUSSION

Epinephrine treatment of food-induced anaphylaxis in the ED has increased over time. There was no clear change for anaphylaxis of any cause. Over the last 10 years, approximately 45% of ED patients with anaphylaxis received epinephrine. A limitation of the evidence is heterogeneity in anaphylaxis definitions.

Grading the severity of anaphylaxis

PURPOSE OF REVIEW

Despite no global consensus on a definition of anaphylaxis, there is increasing recognition that just as allergic reactions lie on a spectrum of severity, the same is for anaphylaxis. A variety of severity scores exist in the literature. We review the approaches taken to develop these scores, and their relative advantages and disadvantages.

RECENT FINDINGS

There have been four recent comparisons of published severity scores. All have highlighted the heterogeneity between scoring systems, and the lack of transferability from one approach to another. Notably, only one score has been developed using a data-driven approach, and none has undergone formal and comprehensive validation.

SUMMARY

It is unclear whether a single severity score is achievable, or indeed desirable. If the aim is to guide management of acute reactions, then assignment of severity is not only unnecessary but might delay treatment and cause harm. Severity scores are needed in the research setting, but require an approach which can discriminate between reactions of similar but nonidentical severity (particularly, nonanaphylaxis reactions). Any approach should be fit for purpose, informed by patient and clinician experience, and ideally be data-driven to minimize subjective bias and facilitate objective validation.

Temporal trends in anaphylaxis ED visits over the last decade and the effect of COVID-19 pandemic on these trends

BACKGROUND

Anaphylaxis is an acute systemic and potentially fatal allergic reaction. We evaluated trends in yearly rates of anaphylaxis in a pediatric Emergency Department (ED) in Montreal, Canada.

METHODS

A prospective and retrospective recruitment process was used to find families of children who had presented with anaphylaxis at the Montreal Children's Hospital between April 2011 and April 2021. Using a uniform recruitment form, data were collected. Anaphylaxis patterns were compared to clinical triggers using descriptive analysis.

RESULTS

Among 830,382 ED visits during the study period, 2726 (26% recruited prospectively) presented with anaphylaxis. The median age was 6 years (IQR: 0.2, 12.00), and 58.7% were males. The relative frequency of anaphylaxis cases doubled between 2011-2015, from 0.22% (95% CI, 0.19, 0.26) to 0.42 March 2020, the total absolute number of anaphylaxis cases and relative frequency declined by 24 cases per month (p < 0.05) and by 0.5% of ED visits (p < 0.05).

CONCLUSIONS

The rate of anaphylaxis has changed over the years, representing modifications in food introduction strategies or lifestyle changes. The decrease in the frequency of anaphylaxis presenting to the ED during the COVID pandemic may reflect decreased accidental exposures with reduced social gatherings, closed school, and reluctance to present to ED.

Canada’s First Joint Oncology-Allergy Clinic: Successful Desensitization to Trastuzumab Following Severe Anaphylactic Reaction in Which Epinephrine Was Inappropriately Withheld

Background: Recognition of anaphylaxis and differentiation from other infusion reactions in an oncology setting is imperative; epinephrine is the recommended treatment for anaphylaxis and should be administered immediately to patients in whom anaphylaxis is suspected. Trastuzumab has a potentially tremendous oncological benefit, and when hypersensitivity reactions occur, rechallenge with desensitization protocols has become more common. Oncology presents a unique situation in which repeat drug exposure after a serious adverse reaction is often warranted due to the mortality risk of untreated cancer—allergists can assist with both symptom assessment and risk mitigation. Case presentation: This case showcases successful desensitization in a 43-year-old female with locally advanced HER2-positive breast cancer following a severe anaphylactic reaction to trastuzumab, in which epinephrine was not administered. We report the establishment of the Medical Oncology and Allergy Clinic: Canada’s first multidisciplinary clinic aimed at expediting the assessment and management of oncology patients with adverse drug reactions (including chemotherapy, contrast media, antimicrobials) and those with primary and acquired immunodeficiency. Conclusions: We propose this multidisciplinary clinic model as a treatment framework moving forward, with the goal of continuing first-line therapies in cancer patients who develop drug-hypersensitivity (i.e., through desensitization). This case highlights the unmet need for a multidisciplinary approach to the management of oncology patients who experience hypersensitivity reactions.

Nutritional Management of Children with Food Allergies

Purpose of the Review

The purpose of the review is to review the evidence for the nutritional management of paediatric food allergy and provide a practical approach for healthcare professionals working in this area.

Recent Findings

Dietary elimination remains the mainstay for management of food allergies in children. However, the elimination of food allergens increases the risk for growth faltering, micronutrient deficiencies and feeding difficulties. Breastmilk remains the ideal source of nutrition for infants, but when not available, the vast majority will tolerate an extensively hydrolysed formula, and rice hydrolysate has also been suggested as a suitable alternative. Only in severe cases, including anaphylaxis, eosinophilic oesophagitis and growth faltering, is an amino acid formula indicated. The early introduction of peanut and egg and avoiding the delay in the introduction of other allergens, when not already allergic, has been highlighted by recent studies.

Summary

Whilst the elimination of allergens increases the risk of developing poor growth, micronutrient deficiencies and feeding difficulties, optimal, early dietary input, including advice on active introduction of allergens and alternative feeds, ideally from a registered dietitian/nutritionist, may be prevent and improve outcomes.

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.

Drug-Related Hypersensitivity Reactions Leading to Emergency Department: Original Data and Systematic Review

The aim of the present study is to describe pharmacological characteristics of drug-related allergies and anaphylaxis leading to the emergency department (ED). An 8-year post hoc analysis on the MEREAFaPS Study database was performed (2012−2019). Subjects who experienced drug-related hypersensitivity leading to an ED visit were selected. Logistic regression analyses were used to estimate the reporting odds ratios (RORs) of drug-related allergies and anaphylaxis adjusting for sex, age classes, and ethnicity. In addition, a systematic review of observational studies evaluating drug-related hypersensitivity reactions leading to ED visits in outpatients was performed. Out of 94,073 ED visits, 14.4% cases were drug-related allergies and 0.6% were anaphylaxis. Females accounted for 56%. Multivariate logistic regression showed a higher risk of drug-related allergy among males and all age classes < 65 years, while a higher risk of anaphylaxis was observed for females (ROR 1.20 [1.01−1.42]) and adults (ROR 2.63 [2.21−3.14]). The systematic review included 37 studies. ED visits related to allergy and anaphylaxis ranged from 0.004% to 88%, and drug-related allergies and anaphylaxis ranged from 0.007% to 88%. Both in our analysis and in primary studies, antibacterials, analgesics, and radiocontrast agents were identified as the most common triggers of hypersensitivity.

Global patterns in anaphylaxis due to specific foods: A systematic review

BACKGROUND

There are increasing global data relating to prevalence of food allergy and food-induced anaphylaxis; however, this is often based on surrogate measures of sensitization rather than objective symptoms at food challenge. In terms of protecting food-allergic consumers from reactions, to our knowledge, there has been no global survey assessing geographic differences in the proportion of anaphylaxis triggered by specific foods.

OBJECTIVE

We sought to identify common triggers for food-induced anaphylaxis and how these vary from country to country.

METHODS

Systematic review of relevant reports published between January 2010 and November 2020. Results were reported following PRISMA guidelines. Publications were screened and data extracted by 2 independent reviewers, and the risk of bias was assessed.

RESULTS

Sixty-five studies (encompassing 41 countries and all 6 regions as defined by the Food and Agriculture Organization of the United Nations) were included. Significant regional variations in the most common triggers of food anaphylaxis were seen; however, in general, there was good agreement between local legislative requirements for allergen disclosure and the most common allergens for each region or nation.

CONCLUSIONS

Local legislation for allergen disclosure generally reflects those allergens commonly responsible for food anaphylaxis. Cow's milk and crustaceans appear to cause a higher proportion of anaphylaxis compared to peanut in some regions.

Knowledge of healthcare providers in the management of anaphylaxis

Introduction

Anaphylaxis is defined as a severe, life-threatening systemic hypersensitivity reaction. Early diagnosis and treatment of a severe allergic reaction requires recognition of the signs and symptoms, as well as classification of severity. It is a clinical emergency, and healthcare providers should have the knowledge for recognition and management. The aim of the study is to evaluate the level of knowledge in the management of anaphylaxis in healthcare providers.

Methods

It is an observational, descriptive, cross-sectional study conducted among healthcare providers over 18 years old via a Google Forms link and shared through different social media platforms. A 12-item questionnaire was applied which included the evaluation of the management of anaphylaxis, from June 2020 to May 2021.

Results

A total of 1023 surveys were evaluated; 1013 met inclusion criteria and were included in the statistical analysis. A passing grade was considered with 8 or more correct answers out of 12; the overall approval percentage was 28.7%. The group with the highest percentage of approval in the questionnaire was health-care providers with more than 30 years of work experience. There was a significant difference between the proportions of approval between all specialty groups, and in a post-hoc analysis, allergy and immunology specialists showed greater proportions of approval compared to general medicine practitioners (62.9% vs 25%; p=<0.001).

Conclusions

It is important that healthcare providers know how to recognize, diagnose, and treat anaphylaxis, and later refer them to specialists in Allergy and Clinical Immunology in order to make a personalized diagnosis and treatment.

Current Guidelines and Future Strategies for the Management of Cow's Milk Allergy

Abstract

Exclusive breast feeding is recommended in all guidelines as the first choice feeding. Cow milk allergy (CMA) can be diagnosed by a diagnostic elimination diet for 2 to 4 weeks with a hypo-allergenic formula, followed by a challenge test with intact cow milk protein. The most often used hypo-allergenic formula for the diagnostic elimination diet and the therapeutic diet is a CM based extensive hydrolysate. CM-based partial hydrolysates cannot be recommended in the management of CMA because of insufficient efficacy and possible reactions, but about half of the infants with CMA may tolerate a partial hydrolysate. The pros and cons of other dietary options are discussed in this paper. The use of an amino acid-based formula and/or rice based hydrolysate formula during the diagnostic elimination and therapeutic diet is debated. When available, there is sufficient evidence to consider rice hydrolysates as an adequate alternative to CM-based hydrolysates, since some infants will still react to the CM hydrolysate. The pros and cons of dietary options such as soy formula, buckwheat, almond, pea or other plant based dietary products are discussed. Although the majority of the plant-based beverages are nutritionally inadequate, some are nutritionally adapted for toddlers. However, accessibility and content vary by country and, thus far there is insufficient evidence on the efficacy and tolerance of these plant-based drinks (except for soy formula and rice hydrolysates) to provide an opinion on them.

Conclusion

A diagnostic elimination diet, followed by a challenge remains the diagnostic standard. The use of an awareness tool may result in a decrease of delayed diagnosis. Breastmilk remains the ideal source of nutrition and when not available a CM extensively hydrolyzed formula, rice hydrolysate or amino acid formula should be recommended. More evidence is needed regarding plant-based drinks.

Fruit-Induced Anaphylaxis: Clinical Presentation and Management

BACKGROUND

Data are sparse regarding the clinical characteristics and management of fruit-induced anaphylaxis.

OBJECTIVE

To assess clinical characteristics and management of patients with fruit-induced anaphylaxis and determine factors associated with severe reactions and epinephrine use.

METHODS

Over 9 years, children and adults presenting with anaphylaxis to seven emergency departments in four Canadian provinces and patients requiring emergency medical services in Outaouais, Quebec were recruited as part of the Cross-Canada Anaphylaxis Registry. A standardized form documenting symptoms, triggers, and management was collected. Multivariate logistic regression was used to identify factors associated with severe reactions and epinephrine treatment in the pre-hospital setting.

RESULTS

We recruited 250 patients with fruit-induced anaphylaxis, median age 10.2 years (interquartile range, 3.6-23.4 years); 48.8% were male. The most common fruit triggers were kiwi (15.6%), banana (10.8%), and mango (9.2%). Twenty-three patients reported having eczema (9.3%). Epinephrine use was low in both the pre-hospital setting and the emergency department (28.4% and 40.8%, respectively). Severe reactions to fruit were more likely to occur in spring and among those with eczema (adjusted odds ratio [aOR] = 1.12, 95% confidence interval [CI], 1.03-1.23; and 1.17, 95% CI, 1.03-1.34, respectively). Patients with moderate and severe reactions (aOR = 1.23; 95% CI, 1.06-1.43) and those with a known food allergy (aOR = 1.38; 95% CI, 1.24-1.54) were more likely to be treated with epinephrine in the pre-hospital setting.

CONCLUSIONS

Severe anaphylaxis to fruit is more frequent in spring. Cross-reactivity to pollens is a potential explanation that should be evaluated further.

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.

Comparison of Clinical Manifestations, Treatments, and Outcomes between Vespidae Sting and Formicidae Sting Patients in the Emergency Department in Taiwan

Background: Hymenopteran stings are the most common animal insult injury encountered in the emergency department. With increasing global spread of imported fire ants in recent decades, the rate of Formicidae assault has become a serious problem in many countries. Formicidae-associated injuries gradually increased in Taiwan in recent decades and became the second most common arthropod assault injury in our ED. The present study aimed at comparing the clinical characteristics of Formicidae sting patients with those of the most serious and common group, Vespidae sting patients, in an emergency department (ED) in Taiwan. Methods: This retrospective study included patients who were admitted between 2015 to 2018 to the ED in a local teaching hospital in Taiwan after a Vespidae or Formicidae sting. Cases with anaphylactic reaction were further compared. Results: We reviewed the records of 881 subjects (503 males, 378 females; mean age, 49.09 ± 17.62 years) who visited our emergency department due to Vespidae or Formicidae stings. A total of 538 (61.1%) were categorized into the Vespidae group, and 343 (38.9%) were sorted into the Formicidae group. The Formicidae group had a longer ED length of stay (79.15 ± 92.30 vs. 108.00 ± 96.50 min, p < 0.01), but the Vespidae group had more cases that required hospitalization (1.9% vs. 0.3%, p = 0.04). Antihistamines (76.8% vs. 80.2%, p < 0.01) were more frequently used in the Formicidae group, while analgesics were more frequently used in the Vespidae group (38.1% vs. 12.5%, p < 0.01). The Vespidae group had more local reactions, and the Formicidae group had more extreme, systemic, or anaphylactic allergic reactions. Creatine kinase was significantly higher in the Vespidae group with an anaphylactic reaction. Sting frequency in both groups exhibited the same positive associations with average temperature of the month and weekend days. Conclusion: Formicidae sting patients presented to the ED with higher rate allergic reactions and spent more time in the ED than Vespidae sting patients. However, Vespidae sting patients had more complications and higher rates of admission, especially with anaphylactic reaction. Laboratory data, especially creatine kinase data, were more valuable to check in Vespidae sting patients with an anaphylactic reaction in the ED. Both groups exhibited positive correlations with temperature and a higher rate on weekend days.

The use of extensively hydrolysed and amino acid feeds beyond cow's milk allergy: a national survey

BACKGROUND

Extensively hydrolysed formulas (EHFs) and amino acid formulas (AAFs) with proven hypoallergenicity are used for children suffering from cow's milk allergy, when breast milk is not available. However, these feeds are often used in other medical conditions where tolerance and absorption of whole protein is affected, frequently without assessment of efficacy. This practice survey assessed the use of these feeds in paediatric conditions other than cow's milk allergy; aiming to describe the population, growth parameters and micronutrient status.

METHODS

Four National Health Service tertiary paediatric centres participated in this practice survey. Inclusion: children between 0 and 18 years, consuming >25% of their estimated energy requirements of an EHF/AAF for any condition other than allergic disease. Anonymised data were collected: (i) descriptive information; (ii) indications; (iii) type and route of feeding; (iv) growth status and nutritional deficiencies; and (v) medication and vitamin and mineral supplementation.

RESULTS

One hundred-and-ninety-one children were included with a median age of 19 months (interquartile range 4-63]. Seventeen percent (33/191) were on AAFs and 83% (158/191) were on EHFs. The feeds were commonly used in cancer for 26% and in critical illness for 31%. The majority (73%) of children had enteral feeds via a nasogastric tube. Nutritional biomarkers were performed in 29% of children and 83% were on a vitamin or mineral supplement.

CONCLUSIONS

This practice survey found that EHFs and AAFs were used in a variety of medical conditions. Indications for feed choice varied, and evidence-based research supporting the use was scarce. Awaiting further research, children on these types of feeds should have regular nutritional monitoring.

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.

Diagnosis and management of Non-IgE gastrointestinal allergies in breastfed infants-An EAACI Position Paper

It is well-established that food proteins, such as egg, soya, cow's milk and wheat, are detectable in breastmilk for many hours or days after ingestion. Exposure to these proteins is important to the process of developing tolerance but can also sometimes elicit IgE-mediated and non-IgE-mediated allergic symptoms in breastfed infants. Non-IgE-mediated allergy, outside of food protein-induced allergic proctocolitis and eosinophilic oesophagitis, is not well understood, leading to variations in the diagnosis and management thereof. A primary objective of the European Academy for Allergy and Clinical Immunology is to support breastfeeding in all infants, including those with food allergies. A Task Force was established, to explore the clinical spectrum of non-IgE-mediated allergies, and part of its objectives was to establish diagnosis and management of non-IgE-mediated allergies in breastfed infants. Eight questions were formulated using the Patient, Intervention, Comparison, Outcome (PICO) system and Scottish Intercollegiate Guideline Network (SIGN) criteria for data inclusion, and consensus was achieved on practice points through the Delphi method. This publication aims to provide a comprehensive overview on this topic with practice points for healthcare professionals.

Global Trends in Anaphylaxis Epidemiology and Clinical Implications

The true global scale of anaphylaxis remains elusive, because many episodes occur in the community without presentation to health care facilities, and most regions have not yet developed reliable systems with which to monitor severe allergic events. The most robust data sets currently available are based largely on hospital admissions, which are limited by inherent issues of misdiagnosis, misclassification, and generalizability. Despite this, there is convincing evidence of a global increase in rates of all-cause anaphylaxis, driven largely by medication- and food-related anaphylaxis. There is no evidence of parallel increases in global all-cause anaphylaxis mortality, with surprisingly similar estimates for case-fatality rates at approximately 0.5% to 1% of fatal outcomes for hospitalizations due to anaphylaxis across several regions. Studying regional patterns of anaphylaxis to certain triggers have provided valuable insights into susceptibility and sensitizing events: for example, the link between the mAb cetuximab and allergy to mammalian meat. Likewise, data from published fatality registers can identify potentially modifiable risk factors that can be used to inform clinical practice, such as prevention of delayed epinephrine administration, correct posturing during anaphylaxis, special attention to populations at risk (such as the elderly on multiple medications), and use of venom immunotherapy in individuals at risk of insect-related anaphylaxis.

Management Strategies Of Idiopathic Anaphylaxis In The Emergency Room: Current Perspectives

Background

Idiopathic anaphylaxis (IA) is a diagnosis of exclusion and represents a major diagnostic and management challenge. There are no current guidelines for diagnosis and management of IA. We aim to present a systematic review of the literature on adult and pediatric IA.

Methods

We conducted a systematic review of original articles published in the past 22 years regarding diagnosis and management strategies of adult and pediatric IA.

Results

The current proposed diagnostic approach and treatment regimens are based on a few small studies. Future large-scale studies are required. IA is a diagnosis of exclusion and should be made only after extensive evaluation excludes potential anaphylaxis triggers as well as non-allergic conditions with a similar presentation. There is currently no diagnostic consensus for IA. Furthermore, the current proposed treatment regimens are limited and rely on prophylactic treatment with antihistamines and prednisone for patients with frequent episodes. However, daily treatment with systemic steroids has well-recognized serious adverse effects. More recently, the use of biologics was suggested to benefit patients with IA, although the optimal management protocol is not yet established.

Conclusion

Future studies are needed to optimize diagnosis and treatment strategies in adult and pediatric cases of IA. Omalizumab may be a promising novel therapeutic option for adult and pediatric IA.

Integrated behavioral health care for management of stress in allergic diseases

OBJECTIVE

This article reviews current findings regarding the management of stress in allergic disease.

DATA SOURCES

The authors use articles and books published between 1995 and 2017. Approximately 85% of sources used were published in the last 10 years, and 60% were published in the last 5 years. Most of the sources are peer-reviewed articles.

STUDY SELECTIONS

Articles that focused on allergic diseases such as allergic rhinitis, food allergies, urticaria, and allergic asthma were included. Articles in which whether the underlying disorder was allergic in nature (for example, nonspecified asthma) were not included. Preference was given to articles published within the past five years.

RESULTS

Patients with allergic diseases, particularly those with chronic or co-occurring allergic diseases, often experience stress and, in turn, this experience of stress can exacerbate disease presentation. High rates of treatment nonadherence in patients with allergic disease also can increase disease burden and stress. Research supports the benefit of behavioral health interventions for patients with allergic disease. Interventions with multidisciplinary teams, which include behavioral health, as well as interventions at the school, workplace, and community level, are recommended.

CONCLUSION

Medical providers working with patients with allergic disease need to address patients' experience of stress and nonadherence to treatment recommendations. This could be done through routine screening and referrals to behavioral health or, ideally, through incorporation of a behavioral health provider within a multidisciplinary patient team.

Short- and long-term management of cases of venom-induced anaphylaxis is suboptimal

BACKGROUND

Venom-induced anaphylaxis (VIA) accounts for severe reactions. However, little is known about the short- and long-term management of VIA patients.

OBJECTIVE

To assess the short- and long-term management of VIA.

METHODS

Using a national anaphylaxis registry (C-CARE), we identified VIA cases presenting to emergency departments in Montreal and to emergency medical services (EMSs) in western Quebec over a 4-year period. Data were collected on clinical characteristics, triggers, and management. Consenting patients were contacted annually regarding long-term management. Univariate and multivariate logistic regressions were used to identify factors associated with epinephrine use, allergist assessment, and administration of immunotherapy.

RESULTS

Between June 2013 and May 2017, 115 VIA cases were identified. Epinephrine was administered to 63.5% (95% confidence interval [CI], 53.9%-72.1%) of all VIA cases by a health care professional. Treatment of reactions without epinephrine was more likely in reactions occurring at home and in nonsevere cases (no hypotension, hypoxia, or loss of consciousness). Among 48 patients who responded to a follow-up questionnaire, 95.8% (95% CI, 84.6%-99.3%) were prescribed epinephrine auto-injector, 68.8% (95% CI, 53.6%-80.9%) saw an allergist who confirmed the allergy in 63.6% of cases, and 81.0% of those with positive testing were administered immunotherapy. Among cases with follow-up, seeing an allergist was less likely in patients with known ischemic heart disease.

CONCLUSION

Almost 30% of patients with suspected VIA did not see an allergist, only two thirds of those seeing an allergist had allergy confirmation, and almost one fifth of those with confirmed allergy did not receive immunotherapy. Educational programs are needed to bridge this knowledge-to-action gap.

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.

Use of Epinephrine in Patients with Drug-Induced Anaphylaxis: An Analysis of the Beijing Pharmacovigilance Database

BACKGROUND

Few studies assessing the use of epinephrine in drug-induced anaphylaxis (DIA) in the hospital setting are available. We utilized the Beijing Pharmacovigilance Database (BPD) to evaluate the appropriateness of epinephrine for DIA management.

METHODS

DIA cases collected in the BPD from January 2004 to December 2014 were adjudicated and analyzed for demographics, causative drugs, clinical signs, outcomes, initial treatment, route, dosing, and cardiovascular adverse events (CAE) of epinephrine.

RESULTS

DIA was primarily caused by antibiotics (38.4%), radiocontrast agents (11.9%), traditional Chinese medicine injections (10.9%), and chemotherapeutic drugs (10.3%). Only 708 (59.5%) patients received epinephrine treatment. Patients who received epinephrine were more likely to experience wheezing (p < 0.001) and respiratory arrest (p < 0.001). Among 518 patients with a complete record of the epinephrine administration route, the percentage of patients receiving it by intramuscular (IM) injection, subcutaneous (SC) injection, intravenous (IV) bolus injection, or IV continuous infusion was 16.9, 31.5, 43.5, and 8.1%, respectively. Among the 427 patients with a record of both the administration route and the dosing, an overdose was more likely with IV bolus (94.1%) in contrast to IM injection (56.6%; p < 0.001) or SC injection (43.7%; p < 0.001). Among the patients analyzed for CAE (n = 349), 17 patients accounted for 19 CAE, and 13 (76.5%) of these patients were overdosed with epinephrine.

CONCLUSION

Underuse, inappropriate IV bolus use, and overdosing were the 3 major problems with epinephrine use in DIA in China. Educational training for health care professionals on the appropriate use of epinephrine in managing anaphylactic reactions is suggested.

Anaphylaxis across two Canadian pediatric centers: evaluating management disparities

BACKGROUND

There are no data on the percentage of visits due to anaphylaxis in the emergency department (ED), triggers, and management of anaphylaxis across different provinces in Canada.

OBJECTIVE

To compare the percentage of anaphylaxis cases among all ED visits, as well as the triggers and management of anaphylaxis between two Canadian pediatric EDs (PEDs).

METHODS

As part of the Cross-Canada Anaphylaxis Registry (C-CARE), children presenting to the British Columbia Children's Hospital (BCCH) and Montreal Children's Hospital (MCH) EDs with anaphylaxis were recruited. Characteristics, triggers, and management of anaphylaxis were documented using a standardized data entry form. Differences in demographics, triggers, and management were determined by comparing the difference of proportions and 95% confidence interval.

RESULTS

Between June 2014 and June 2016, there were 346 visits due to anaphylaxis among 93,730 PED visits at the BCCH ED and 631 anaphylaxis visits among 164,669 pediatric visits at the MCH ED. In both centers, the majority of cases were triggered by food (BCCH 91.3% [88.7, 94.0], MCH 82.4% [79.7, 85.3]), of which peanuts were the most common culprit (24.7% [20.9, 29.9] and 19.0% [15.8, 22.7], respectively). Pre-hospital administration of epinephrine (BCCH 27.7% [23.2, 32.8], MCH 33.1% [29.5, 37.0]) and antihistamines (BCCH 50.6% [45.2, 56.0], MCH 47.1% [43.1, 51.0]) was similar. In-hospital management differed in terms of increased epinephrine, antihistamine, and steroid use at the BCCH (59.2% [53.9, 64.4], 59.8% [54.4, 65.0], and 60.1% [54.7, 65.3], respectively) compared to the MCH (42.2% [38.3, 46.2], 36.2% [32.5, 40.1], and 11.9% [9.5, 14.8], respectively). Despite differences in management, percentage of cases admitted to the intensive care unit was similar between the two centers.

CONCLUSION

Compared to previous European and North American reports, there is a high percentage of anaphylaxis cases in two PEDs across Canada with substantial differences in hospital management practices. It is crucial to develop training programs that aim to increase epinephrine use in anaphylaxis.

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.

Anaphylaxis and ethnicity: higher incidence in British South Asians

BACKGROUND

The incidence of anaphylaxis in South Asians (Indian, Pakistani and Bangladeshi ethnicity) is unknown. Birmingham is a British city with a disproportionately large population of South Asians (22.5%) compared with the rest of the UK (4.9%). The main aims of this study were to determine the incidence and severity of anaphylaxis in this population and to investigate the differences between the South Asian and White populations.

METHODS

A retrospective electronic search of emergency department attendances at three hospitals in Birmingham during 2012 was carried out. Wide search terms were used, medical notes were scrutinized, and the World Allergy Organization diagnostic criteria for anaphylaxis were applied. Patients' age, sex, ethnicity and home postal code were collected, reactions were graded by severity, and other relevant details including specialist assessment were extracted. Multivariate analysis was undertaken using 2011 UK census data.

RESULTS

Age-, sex- and ethnicity-standardized incidence rate of anaphylaxis was 34.5 per 100 000 person-years. Multivariate logistic regression which controlled for the confounders of age, sex and level of socioeconomic deprivation showed that incidence was higher in the South Asian population (OR 1.48, P = 0.005). Incidence rate in the South Asian population was 58.3 cases per 100 000 person-years compared to 31.5 in the White population. South Asian children were more likely to present with severe anaphylaxis (OR 5.31, P = 0.002).

CONCLUSIONS

Incidence of anaphylaxis is significantly higher in British South Asians compared to the white population. British South Asian children are at a greater risk of severe anaphylaxis than White children.

2015 update of the evidence base: World Allergy Organization anaphylaxis guidelines

The World Allergy Organization (WAO) Guidelines for the assessment and management of anaphylaxis provide a unique global perspective on this increasingly common, potentially life-threatening disease. Recommendations made in the original WAO Anaphylaxis Guidelines remain clinically valid and relevant, and are a widely accessed and frequently cited resource. In this 2015 update of the evidence supporting recommendations in the Guidelines, new information based on anaphylaxis publications from January 2014 through mid- 2015 is summarized. Advances in epidemiology, diagnosis, and management in healthcare and community settings are highlighted. Additionally, new information about patient factors that increase the risk of severe and/or fatal anaphylaxis and patient co-factors that amplify anaphylactic episodes is presented and new information about anaphylaxis triggers and confirmation of triggers to facilitate specific trigger avoidance and immunomodulation is reviewed. The update includes tables summarizing important advances in anaphylaxis research.

Anaphylaxis cases presenting to primary care paramedics in Quebec

Data on anaphylaxis cases in pre-hospital settings is limited. As part of the Cross Canada Anaphylaxis Registry (C-CARE), we assessed anaphylaxis cases managed by paramedics in Outaouais, Quebec. A software program was developed to prospectively record demographic and clinical characteristics as well as management of cases meeting the definition of the anaphylaxis. Univariate and multivariate logistic regressions were compared to assess factors associated with severity of reactions and epinephrine use. Among 33,788 ambulance calls of which 23,486 required transport, 104 anaphylaxis cases were identified (anaphylaxis rate of 0.31% [95%CI, 0.25%, 0.37%] among all ambulance calls and 0.44% [95%CI, 0.36%, 0.54%] among those requiring transport). The median age was 46.8 years and 41.3% were males. The common triggers included food (32.7% [95%CI, 24.0%, 42.7%]), drugs (24.0% [16.4%, 33.6%]), and venom (17.3% [10.8%, 26.2%]). Among all reactions, 37.5% (95%CI, 28.4%, 47.6%) were severe. Epinephrine was not administered in 35.6% (95%CI, 26.6%, 45.6%) of all cases. Males were more likely to have severe reactions (Odds ratio [OR]: 2.50 [95%CI, 1.03, 6.01]). Venom-induced reactions and severe anaphylaxis were more likely to be managed with epinephrine (OR: 6.9 [95%CI, 1.3, 35.3] and 4.2 [95%CI, 1.5, 12.0], respectively). This is the first prospective study evaluating anaphylaxis managed by paramedics. Anaphylaxis accounts for a substantial proportion of the cases managed by paramedics in Outaouais, Quebec and exceeds prior reports of the proportion of Quebec emergency room visits attributed to anaphylaxis. Although guidelines recommend prompt use of epinephrine for all cases of anaphylaxis, more than a third of cases did not receive epinephrine. It is crucial to develop educational programs targeting paramedics to promote the use of epinephrine in all cases of anaphylaxis regardless of the specific trigger.