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

Changes in epinephrine dispensings and allergy hospitalisations in Sweden in the years following the removal of autoinjector co-payments

Introduction

To understand any possible healthcare system benefits and changes of behavior for the patients with the change in prescription co-payment in Sweden we aimed to provide an update on the trends of EAI dispensings and hospitalizations for the Swedish paediatric population (ages 0-19 years), from 2018 to 2022, including by sex and geographic region.

Methods

Using publically-available, population-level aggregate data from Sweden's National Board of Health and Welfare, we extracted information on annual epinephrine (ATC C01CA24) dispensings per 1,000 inhabitants from 2018 to 2023, overall, as well as stratified by sex, age groups and geographic region; and on inpatient stays 2018-2022 (ICD-10 code T78), anaphylaxis and other allergic reactions, per 100,000 individuals. We compared these estimates to those for adults ages 18 + years, for whom prescription co-payments remained in place.

Results

EAI dispensings remained stable for children and adults across the study period, with the exception of statistically significant decreases amongst dispensings for children across all ages in 2021 (6.65/1,000) and 2022 (7.37/1,000), compared to 2018 (8.63/1,000) (each year p = 0.03 compared to 2018 dispensings). National EAI dispensings did not statistically significantly differ from 2018 (8.63/1,000) to 2023 (6.70/1,000) amongst children. EAI dispensings for children ages 5 + years consistently exceed dispensings for adults per 1,000 inhabitants; only children aged 0-4 years had proportionately fewer dispensings. Children ages 0-4 years tended to be hospitalised more often than older children, albeit these differences were not statistically significant (all p > 0.97).

Conclusion

Subsequent to the removal of out-of-pocket costs for EAI, dispensings did not increase for children, although more EAI were dispensed to children from age 5 years, compared to younger children. Allergy-related hospitalisations were highest amongst children ages 0-4, lower amongst children ages 5-14 years, and again higher amongst those ages 15-19 years.

Trends in Childhood Anaphylaxis in Singapore: 2015-2022

BACKGROUND

There has been limited data regarding the incidence of anaphylaxis in Asia. We aim to describe patterns in patient characteristics, triggers and clinical presentation of childhood anaphylaxis in Singapore.

METHODS

This was a retrospective review of emergency electronic medical records of children with anaphylaxis. Patients with the allergy-related diagnoses of anaphylaxis, angioedema, allergy and urticaria based on ICD-9 codes were screened. Cases fulfilling the World Allergy Organization criteria for anaphylaxis were included.

RESULTS

A total of 1188 cases of anaphylaxis were identified with a median age of 6.3 years. Extrapolating data from the study sites, from 2015 to 2022, the incidence rate of childhood anaphylaxis emergency visits in Singapore doubled from 18.9 to 38.8 per 100,000 person-years, with an incidence rate ratio (IRR) of 2.06 (95% confidence interval [CI] 1.70-2.49). In 2022, the incidence rate of food anaphylaxis was 30.1 per 100,000 person-years, IRR 2.39 (95% CI 1.90-3.01) and drug anaphylaxis was 4.6 per 100,000 person-years, IRR 1.89 (95% CI 1.11-3.25). The incidence rate in children aged 0-4 years quadrupled during the study period. Common triggers were egg (10.4%), peanut (9.3%), tree nut (8.8%), milk (8%), shellfish (7.8%) and non-steroidal anti-inflammatory drug (4.4%). The majority (88.6%) of patients were treated with intramuscular adrenaline. Total number of allergy-related visits did not increase over time between 2015 and 2019. Rates of severe anaphylaxis, namely anaphylactic shock and admission to high-dependency and intensive care, did not increase over time, with a mean incidence of 1.6, IRR 0.85 (95% CI 0.40-1.83) and 0.7, IRR 1.77 (95% CI 0.54-5.76) per 100,000 person-years, respectively.

CONCLUSION

While the number of emergency visits due to childhood anaphylaxis has increased, the number of cases of allergy-related visits, anaphylactic shock and anaphylaxis requiring high-dependency and intensive care did not rise.

Allergic multimorbidity is associated with self-reported anaphylaxis in adults-A cross-sectional questionnaire study

Background

Anaphylaxis has increased over the last two decades in Europe, reaching an estimated prevalence of 0.3% and an incidence of 1.5-7.9 per 100,000 person-years. Allergic multimorbidity is associated with asthma severity, yet its role in anaphylaxis is not fully understood. Our aim was to study association between allergic multimorbidity and anaphylaxis in adults.

Methods

We used population-based data from the Finnish Allergy Barometer Study (n = 2070, age range: 5-75). Food allergy (FA), atopic dermatitis (AD), allergic rhinitis (AR) and allergic conjunctivitis (AC), were defined from a self-completed questionnaire. A logistic regression adjusted on potential confounders (sex, age, smoking status) was applied to estimate the anaphylaxis risk associated with allergic multimorbidity.

Results

1319 adults with at least one allergic disease (FA, AD, AR, AC) with/without asthma (AS) were included. Of these, 164 had self-reported anaphylaxis [mean (SD, min-max) 54 (14, 22-75) years, 17% men]. AS, FA, AR, AC, or AD were reported by 86.0%, 62.2%, 82.3%, 43.3%, and 53.7% of subjects with anaphylaxis and respectively by 67.8%, 29.5%, 86.2%, 29.4%, and 34.4% of subjects without anaphylaxis. Compared with subjects exhibiting only one allergic disease, the risk of anaphylaxis increased with the number of allergic diseases; adjusted odds ratios (OR) [CI95%] for two, three, four and five coinciding allergic diseases were 1.80 [0.79-4.12], 3.35 [1.47-7.66], 7.50 [3.25-17.32], and 13.5 [5.12-33.09], respectively. The highest risk of anaphylaxis (6.47 [4.33-9.92]) was associated with FA + AS or their various variations with AR/AC/AD embodied, when compared with AR, AC, and AS separately or their combinations.

Conclusions

Anaphylaxis was positively associated with the number of allergic diseases a subject exhibited and with subgroups including FA and/or AS. The results can be applied when estimating the risk of anaphylaxis for individual patients.

Billing fees for various common allergy tests vary widely across Canada

Background

The prevalence of food allergy in Canada is high and has increased over time. To date, there are no Canadian data on the healthcare costs of visits to allergists.

Methods

We sent an anonymous survey to allergist members of the Canadian Society of Allergy and Clinical Immunology (CSACI) between October and December 2019. Survey questions included demographic information and billing fees for various types of allergy visits and diagnostic testing.

Results

Of 200 allergists who are members of CSACI, 43 allergists responded (21.5% response rate). Billing fees varied widely. The greatest ranges were noted for oral immunotherapy (OIT; both initial consultation [mean $198.70; range $0 to $575] and follow up/build up visits [mean $125.74; range: $0 to $575]). There were significant provincial differences in billing fees, as well as significant billing fee differences between hospital versus community allergists (e.g. oral food challenge [OFC]: $256.38 vs. $134.94, p < 0.01). Billing fees were higher outside of Ontario, with the exception of specific Immunoglubulin E (sIgE) testing and OIT visits.

Conclusions

Greater standardization of billing fees across provinces and between hospital versus community allergy could result in more consistency of billing fees for OFC and OIT across Canada. Further knowledge of exact costs will help inform practice and policy in the diagnosis and management of food allergy.

IgE-Mediated Systemic Anaphylaxis And Its Association With Gene Polymorphisms Of ACE, Angiotensinogen And Chymase

BACKGROUND

The renin-angiotensin system (RAS) protects the circulation against sudden falls in systemic blood pressure via generation of angiotensin II (AII). Previously, we demonstrated that patients with anaphylaxis involving airway angioedema and cardiovascular collapse (AACVS) had significantly increased "I" gene polymorphisms of the angiotensin-converting-enzymes (ACE). This is associated with lower serum ACE and AII levels and was not seen in anaphylaxis without collapse nor atopics and healthy controls.

OBJECTIVES

To examine the angiotensinogen (AGT-M235T) and chymase gene (CMA-1 A1903G) polymorphisms in these original subjects.

METHOD

122 patients with IgE-mediated anaphylaxis, 119 healthy controls and 52 atopics had polymorphisms of the AGT gene and chymase gene examined by polymerase chain reactions and gel electrophoresis. Their previous ACE genotypes were included for the analysis.

RESULTS

AGT-MM genes (associated with low AGT levels) were significantly increased in anaphylaxis (Terr's classification). When combined with ACE, anaphylaxis showed increased MM/II gene pairing (p<0.0013) consistent with lower RAS activity. For chymase, there was increased pairing of MM/AG (p<0.005) and AG/II and AG/ID (p<0.0073) for anaphylaxis consistent with lower RAS activity. A tri-allelic ensemble of the 6 commonest gene combinations for the healthy controls and anaphylaxis confirmed this difference (p=0.0001); for anaphylaxis, genes were predominately MM/AG/II or ID, while healthy controls were DD/MT/AG or GG patterns.

CONCLUSION

Our gene polymorphisms show lower RAS activity for anaphylaxis especially AACVS. Animal models of anaphylaxis are focused on endothelial nitric oxide (eNO) which is shown to be the mediator of fatal shock and prevented by eNO-blockade. The interaction of AII and eNO controls the microcirculation in man. High serum AII levels reduce eNO activity, so higher RAS-activity could protect against shock. Our data shows low RAS activity in anaphylaxis especially AACVS, suggesting the influence of these genes on shock are via AII levels and its effects on eNO.

Food allergy endotype with high risk of severe anaphylaxis in children-Monosensitization to cashew 2S albumin Ana o 3

BACKGROUND

Food allergy in children can be life-threatening. Component-resolved diagnostics approach to food anaphylaxis is rarely assessed in children. The aim of the study was to identify the food allergen components as the triggers responsible for severe anaphylaxis, with regard to characteristics and associated risks, among children in a large, population-based setting.

METHODS

Two hundred and seventy-one children who were hospitalized due to systemic allergic reaction (SAR) and food anaphylaxis were recruited. Medical history was assessed, and culprit allergen source and anaphylaxis severity grade were established. Specific IgE to 112 allergen components using multiplex ImmunoCAP ISAC immunoassay and specific IgE to hazelnut, Cor a 14, and cashew, Ana o 3, using singleplex ImmunoCAP immunoassay were determined.

RESULTS

We analyzed data from 237 SAR/anaphylaxis in 237 children. Trigger at allergen component level was defined for every episode. The most common triggers of SAR/anaphylaxis were seeds (50.6%), among them, the storage proteins. Anaphylaxis triggered by Ana o 3, 2S albumin from cashews (aOR = 15.0; 95% CI: 3.27 to 73.47); Tri a 19 from wheat (aOR = 9.93; 95% CI: 1.73 to 56.97); and Cor a 9 from hazelnut (aOR = 6.53; 95% CI: 1.16 to 36.72) had the worst clinical presentation including cardiovascular and severe respiratory symptoms (grade IV-V vs I-III in Cox scale). Thirteen out of 237 (5.5%) SAR/anaphylaxis patients were triggered by Ana o 3. Almost 82% of patients with severe Ana o 3 anaphylaxis were sensitized only to this component and had no concomitant food sensitization.

CONCLUSION

Monosensitization to Ana o 3 is, irrespective of other parameters, connected with high risk of severe anaphylaxis.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Drug reaction with eosinophilia and systemic symptoms (DRESS) in children

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a severe reaction to drugs. Incidence of DRESS in children is not well known and the mortality rate seems to be lower than 10%. Anticonvulsants are the main drugs involved both in adults and in children. The treatment of choice is intravenous immunoglobulins and corticosteroids used in synergy. Today there are not controlled clinical trials regarding DRESS treatment in children. Anyway, the prompt withdrawn of the offending drug is of paramount importance for a better prognosis. DRESS sequels may occur, consequently, follow-up visits are required at least until the first year after the reaction. (www.actabiomedica.it)

No difference in human mast cells derived from peanut allergic versus non-allergic subjects

INTRODUCTION

Mast cells are the primary effector cells of allergy. This study aimed at characterizing human peripheral blood-derived mast cells (PBdMC) from peanut allergic and non-allergic subjects by investigating whether the molecular and stimulus-response profile of PBdMC discriminate between peanut allergic and healthy individuals.

METHODS

PBdMC were generated from eight peanut allergic and 10 non-allergic subjects. The molecular profile (cell surface receptor expression) was assessed using flow cytometry. The stimulus-response profile (histamine release induced by secretagogues, secretion of cytokines/chemokines and changes in miRNA expression following anti-IgE activation) was carried out with histamine release test, luminex multiplex assay and miRNA arrays.

RESULTS

Expression of activating receptors (FcϵRI, CD48, CD88, CD117, and C3aR) on PBdMC was not different among peanut allergic and non-allergic subjects. Likewise, inhibitory receptors (CD32, CD200R, CD300a, and siglec-8) displayed comparable levels of expression. Both groups of PBdMC were unresponsive to substance P, compound 48/80 and C5a but released comparable levels of histamine when stimulated with anti-IgE and C3a. Interestingly, among the secreted cytokines/chemokines (IL-8, IL-10, IL-13, IL-23, IL-31, IL-37, MCP-1, VEGF, GM-CSF) PBdMC from peanut allergic subjects showed a different secretion pattern of IL-31 compared to non-allergic subjects. Investigating miRNA expression from resting or activated PBdMC revealed no significantly difference between peanut allergic and non-allergic subjects.

CONCLUSION

The molecular and stimulus-response profile revealed that PBdMC from peanut allergic subjects differently express IL-31 compared to non-allergic subjects. However, since only one altered parameter was found among 893 investigated, it is still questionable if the pathophysiological mechanisms of peanut allergy are revealed in PBdMC.

When nutrition and allergy collide: the rise of anaphylaxis to plant foods

PURPOSE OF REVIEW

Interest in nutrition is increasing, but in the world of internet health gurus, whilst the nutritional benefits of fruits and vegetables are extolled, wheat is often vilified. This review will assess the positive nutritional effects of plant foods in relation to allergy prevention, the effectiveness of gluten-avoidance and the likelihood of anaphylaxis to fruits and vegetables.

RECENT FINDINGS

Although the numbers of people who report gluten sensitivity is rising, hard evidence of mass sensitivity to gluten is scant. Also, the avoidance of wheat containing foods could lead to nutritional imbalance and effects on the gut microbiome. The evidence that fruits and vegetables have a protective effect on the development of allergy is inconsistent, although fruit juices may promote beneficial changes to gut microflora. Fruits and vegetables can cause severe allergic reactions, especially due to the presence of lipid transfer proteins, but this is not just a Mediterranean phenomenon, and not limited to peaches.

SUMMARY

These findings emphasise the importance of a keeping an open mind about reported reactions to plant foods, to ensure the correct diagnosis is made and nutrition is optimised to prevent any adverse effects of avoidance on the gut microbiome.

Developments in the field of allergy in 2016 through the eyes of Clinical and Experimental Allergy

In this article, we described the development in the field of allergy as described by Clinical and Experimental Allergy in 2016. Experimental models of allergic disease, basic mechanisms, clinical mechanisms, allergens, asthma and rhinitis, and clinical allergy are all covered.