Occupational anaphylaxis-Data from the anaphylaxis registry.

BACKGROUND: Epidemiologic data on occupational anaphylaxis is scarce, and there is a need of more knowledge about work-related anaphylactic episodes. METHODS: Based on the data of the Anaphylaxis Registry, we identified cases related to occupational exposure and analyzed the elicitors, demographics, severity of clinical reaction and management. RESULTS: Since 2017, 5851 cases with an information about the occupational relation of the anaphylactic episode were registered whereby 225 (3.8%) were assigned to be caused by an occupational allergen. The vast majority of these occupational anaphylaxis cases were caused by insects (n = 186, 82.7%) followed by food (n = 27, 12.0%) and drugs (n = 8, 3.6%). Latex elicited occupational anaphylaxis in only two cases. Beekeepers, gardeners, farmers, and individuals working in professions associated with food handling, for example, employees in restaurants, bakery, pastry, and cooks were most frequently affected. The comparison of the occupational insect venom-induced anaphylaxis to a group of non-occupational insect anaphylaxis in adults (n = 1842) revealed a significant younger age in occupational anaphylaxis (46 vs. 53 years), a predominance of bee-induced cases (38% vs. 17%), and a higher rate of venom immunotherapy in a primary care setting (3.3% vs. 1.3%, p = .044). In the occupational- versus non-occupational adults with food-induced anaphylaxis atopic dermatitis as concomitant atopic disease was observed more frequently (n = 486; 20% vs. 10%), although this was not significant. CONCLUSION: Our data demonstrate the impact of venom allergy in work-related anaphylaxis. Foods and drugs are less frequently elicitors, and latex-induced occupational anaphylaxis was rare. More data are needed to determine risk factors associated with occupational anaphylaxis.

Health-related quality of life in food and venom induced anaphylaxis and role of influencing factors.

The impact on health-related quality of life (HRQL) plays a key role for patients suffering from allergies and anaphylaxis. In this narrative review we review the HRQL in allergic patients suffering from food and venom allergy, both being the most frequent elicitors of severe allergic, potential life-threatening reactions and provide an overview on the current knowledge and identified gaps. The data show that for food and venom allergy standardized assessment tools to measure HRQL are available and have been successfully applied. Our analysis shows that multiple factors can modulate HRQL in these patient groups. These include sociodemographic data like patients' age and sex, fear of accidental reactions but also external factors like the social environment and the appreciation of the seriousness of the condition by others. External factors may have a significant impact on HRQL and should be considered in patient-related outcome assessments to avoid biased measurements possibly affecting the results. The assessment of the quality of life in the context of specific immunotherapy should consider lifestyle factors and ideally, the individual change in HRQL should be measured. Although there are many data indicating a negative impact on HRQL in food allergic children and their caregivers, limited data are existing from adults with food allergy and venom allergic patients from all age groups. Also, the use of standardized questionnaires should be extended to allow for a better comparability of results between studies. Therefore, translation to additional languages is necessary. Taken together, the eliciting allergen, the severity of the allergic disease but moreover multiple external factors impact the outcome in HRQL and should be considered in HRQL assessment.

Different phenotypes of drug-induced anaphylaxis-Data from the European Anaphylaxis Registry.

BACKGROUND: Drugs are a frequent cause of severe anaphylactic reactions. Here, we analyze a large dataset on drug induced anaphylaxis regarding elicitors, risk factors, symptoms, and treatment. METHODS: Data from the European Anaphylaxis Registry (2007-2019) with 1815 reported cases of drug-induced anaphylaxis were studied accordingly. RESULTS: Drugs are the third most frequent cause of anaphylaxis reported in the Anaphylaxis Registry. Among the eliciting groups of drugs analgesics and antibiotics were far most often reported. Female and senior patients were more frequently affected, while the number of children with DIA was low. DIA patients had symptoms affecting the skin and mucous membranes (n = 1525, 84.02%), the respiratory (n = 1300, 71.63%), the cardiovascular (n = 1251, 68.93%) and the gastrointestinal system (n = 549, 30.25%). Drugs caused significant more severe reactions, occurred more often in medical facilities and led to increased hospitalization rates in comparison to food and insect venom induced anaphylaxis. Adrenaline was used more often in patients with DIA than in anaphylaxis due to other causes. Patients with skin symptoms received more antihistamines and corticosteroids in the acute treatment, while gastrointestinal symptoms led to less adrenaline use. CONCLUSION: The study contributes to a better understanding of DIA, with a large number of cases from Europe supporting previous data, e.g., analgesics and antibiotics being the most frequent culprits for DIA. Female gender and higher age are relevant risk factors and despite clear recommendations, the emergency treatment of DIA is not administered according to the guidelines.

Elicitors and phenotypes of adult patients with proven IgE-mediated food allergy and non-immune-mediated food hypersensitivity to food additives.

BACKGROUND: Food allergy is a growing health concern with a prevalence of 2%-3% in the adult population in Europe. Non-immune-mediated food hypersensitivities, which include reactions after ingestion of food additives, affect 1% of adults and may resemble IgE-induced allergic reactions without identifiable immunologic sensitization. A double-blind placebo-controlled food challenge (DBPCFC) is the gold standard for the diagnosis of any food hypersensitivity. OBJECTIVE: We analysed a large group of adult patients with suspected food hypersensitivity, who had undergone DBPCFC, to better understand IgE-mediated food allergy and non-immune-dependent food hypersensitivity to food additives in adults regarding elicitors, symptoms and positivity rates of oral challenges. METHODS: Data from 541 patients with suspected food hypersensitivity were analysed, who underwent an oral food challenge between 2010 and 2019. RESULTS: IgE-dependent food allergy was confirmed in 114 of 329 adult patients (34.6%). The confirmation rate was lower in the group of patients with suspected non-immune-mediated reactions to food additives (65 of 286, 22.7%). Urticaria and angioedema appeared more frequently in patients with IgE-mediated food allergies. By contrast, flush and diarrhoea were the most frequent symptoms after a challenge in the group with the non-immune-mediated reactions to food additives. Wheat and celery were the most frequently identified food allergens in adults, whereas colourings and preservatives were the most frequent elicitors of non-immune-mediated food hypersensitivity. CONCLUSION: The importance of oral food challenges for the diagnosis of food hypersensitivity is confirmed. IgE-dependent food allergy is more frequently proven, reaching a positivity rate of one-third and only about 20% for non-immune-mediated hypersensitivity. Future studies should elaborate on the mechanisms of non-immune-mediated food hypersensitivity and the clinical impact of cofactors in this setting.

Development and validation of the food allergy severity score.

BACKGROUND: The heterogeneity and lack of validation of existing severity scores for food allergic reactions limit standardization of case management and research advances. We aimed to develop and validate a severity score for food allergic reactions. METHODS: Following a multidisciplinary experts consensus, it was decided to develop a food allergy severity score (FASS) with ordinal (oFASS) and numerical (nFASS) formats. oFASS with 3 and 5 grades were generated through expert consensus, and nFASS by mathematical modeling. Evaluation was performed in the EuroPrevall outpatient clinic cohort (8232 food reactions) by logistic regression with request of emergency care and medications used as outcomes. Discrimination, classification, and calibration were calculated. Bootstrapping internal validation was followed by external validation (logistic regression) in 5 cohorts (3622 food reactions). Correlation of nFASS with the severity classification done by expert allergy clinicians by Best-Worst Scaling of 32 food reactions was calculated. RESULTS: oFASS and nFASS map consistently, with nFASS having greater granularity. With the outcomes emergency care, adrenaline and critical medical treatment, oFASS and nFASS had a good discrimination (receiver operating characteristic area under the curve [ROC-AUC]>0.80), classification (sensitivity 0.87-0.92, specificity 0.73-0.78), and calibration. Bootstrapping over ROC-AUC showed negligible biases (1.0 × 10-6 -1.23 × 10-3 ). In external validation, nFASS performed best with higher ROC-AUC. nFASS was strongly correlated (R 0.89) to best-worst scoring of 334 expert clinicians. CONCLUSION: FASS is a validated and reliable method to measure severity of food allergic reactions. The ordinal and numerical versions that map onto each other are suitable for use by different stakeholders in different settings.

Phenotype and risk factors of venom-induced anaphylaxis: A case-control study of the European Anaphylaxis Registry.

BACKGROUND: Venom-induced anaphylaxis (VIA) is a common, potentially life-threatening hypersensitivity reaction associated with (1) a specific symptom profile, 2) specific cofactors, and 3) specific management. Identifying the differences in phenotypes of anaphylaxis is crucial for future management guidelines and development of a personalized medicine approach. OBJECTIVE: This study aimed to evaluate the phenotype and risk factors of VIA. METHODS: Using data from the European Anaphylaxis Registry (12,874 cases), we identified 3,612 patients with VIA and analyzed their cases in comparison with sex- and age-matched anaphylaxis cases triggered by other elicitors (non-VIA cases [n = 3,605]). RESULTS: VIA more frequently involved more than 3 organ systems and was associated with cardiovascular symptoms. The absence of skin symptoms during anaphylaxis was correlated with baseline serum tryptase level and was associated with an increased risk of a severe reaction. Intramuscular or intravenous epinephrine was administered significantly less often in VIA, in particular, in patients without a history of anaphylaxis. A baseline serum tryptase level within the upper normal range (8-11.5 ng/mL) was more frequently associated with severe anaphylaxis. CONCLUSION: Using a large cohort of VIA cases, we have validated that patients with intermediate baseline serum tryptase levels (8-11 ng/mL) and without skin involvement have a higher risk of severe VIA. Patients receiving ß-blockers or angiotensin-converting enzyme inhibitors had a higher risk of developing severe cardiovascular symptoms (including cardiac arrest) in VIA and non-VIA cases. Patients experiencing VIA received epinephrine less frequently than did cases with non-VIA.

[Influence of nut and peanut allergy on the quality of life of adults]. / Einfluss der Nuss- und Erdnussallergie auf die Lebensqualität bei Erwachsenen.

BACKGROUND: Health-related quality of life is negatively affected in patients with food allergies. AIM: Analysis of health-related quality of life of adults allergic to tree nuts or peanuts. METHODS: Health-related quality of life was analysed via the Food Allergy Quality of Life Questionnaire - Adult Form (FAQLQ-AF) and the Short Form 12 (SF12) questionnaire. In addition, a diagnostic workup including a detailed patient history, skin prick test and analysis of specific IgE was performed. An oral food challenge was offered to all patients. RESULTS: Food allergic patients (n = 63) reported an average burden of 3.91 ± 1.41 points on the FAQLQ-AF and 3.31 ± 1.03 points on the Food Allergy Independent Measure (FAIM), a measure for the perceived disease severity. A higher mean FAIM score was the most important predictor of higher results (worse quality of life) in the FAQLQ-AF. The SF12 questionnaire was not able to discriminate between food allergic patients and healthy controls (n = 16). CONCLUSION: A tree nut and/or peanut allergy was perceived as an impairment of health-related quality of life, which is directly associated with the perceived severity of disease. Disease-specific quality of life questionnaires can capture the burden associated with peanuts or tree nuts allergies.

[Management of severe nut allergy in adults]. / Management einer schweren Nussallergie im Erwachsenenalter.

We present a case of walnut allergy in a 24-year-old man. The allergy work up revealed sensitization to walnut including a positive skin prick test and a high value of walnut-specific IgEs. The patient showed an anaphylactic reaction during the double blind placebo-controlled food challenge, to a cumulative dose of 3.723 g of walnut protein. The oral food challenge resulted in counseling regarding strict walnut avoidance and optimization of the emergency management. At follow-up the patient reported that having adhered to the recommended dietary measures resulted in no further allergic reactions.

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

BACKGROUND: Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%-1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents. METHODS: Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre. RESULTS: 3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004). CONCLUSIONS: The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.

Secondary prevention measures in anaphylaxis patients: Data from the anaphylaxis registry.

BACKGROUND: Patients with a history of anaphylaxis are at risk of future anaphylactic reactions. Thus, secondary prevention measures are recommended for these patients to prevent or attenuate the next reaction. METHODS: Data from the Anaphylaxis Registry were analyzed to identify secondary prevention measures offered to patients who experienced anaphylaxis. Our analysis included 7788 cases from 10 European countries and Brazil. RESULTS: The secondary prevention measures offered varied across the elicitors. A remarkable discrepancy was observed between prevention measures offered in specialized allergy centers (84% of patients were prescribed adrenaline autoinjectors following EAACI guidelines) and outside the centers: Here, EAACI guideline adherence was only 37%. In the multivariate analysis, the elicitor of the reaction, age of the patient, mastocytosis as comorbidity, severity of the reaction, and reimbursement/availability of the autoinjector influence physician's decision to prescribe one. CONCLUSIONS: Based on the low implementation of guidelines concerning secondary prevention measures outside of specialized allergy centers, our findings highlight the importance of these specialized centers and the requirement of better education for primary healthcare and emergency physicians.

Contact urticaria: Frequency, elicitors and cofactors in three cohorts (Information Network of Departments of Dermatology; Network of Anaphylaxis; and Department of Dermatology, University Hospital Erlangen, Germany).

BACKGROUND: Contact urticaria (CU) is an infrequent, mostly occupational disease that may be life-threatening (CU syndrome stage 4). OBJECTIVES: To identify the current frequency, elicitors and cofactors of CU. PATIENTS: Three cohorts were retrospectively analysed for CU: (a) patients from the Information Network of Departments of Dermatology (IVDK) database (2000-2014; n = 159 947); (b) patients from an allergy unit (Department of Dermatology, University Hospital Erlangen, 2000-2015; n = 4741); and (c) patients from the Anaphylaxis Registry (2007-2015: 6365 reported cases, including 2473 patients with Ring and Messmer grade III-IV reactions) for severe cases with skin/mucosal manifestations occurring at the workplace vs cases not occurring at the workplace (n = 68 vs n = 1821). RESULTS: Four hundred and forty-eight CU patients (0.28%) were diagnosed in the IVDK cohort, and 16 (0.34%) (10 of immunological aetiology, and 6 of non-immunological aetiology) in the Erlangen cohort. The most frequent elicitors in the IVDK cohort were cosmetics, creams, sun protection agents (although these were less frequent in CU patients than in controls without CU; 26.8% vs 35.6%, P < .0001), and gloves (significantly more frequent in CU patients than in controls; 18.1% vs 6.5%, P < .0001). The most frequent elicitors in the Erlangen cohort were natural rubber latex and sorbic acid. Among the MOAHLFA index characteristics, in both cohorts occupational disease was more common in CU patients than in patients without CU. CU was significantly associated with allergic rhinitis and allergic asthma. Wet work was a relevant cofactor. In the Anaphylaxis Registry, 19 cases (0.3%) were identified with severe reactions including skin symptoms at the workplace linked to common occupational elicitors. CONCLUSIONS: CU is a rare occupational skin manifestation with a frequency of <0.4% in the examined patients; it may, however, progress to anaphylaxis. Preventive measures are important, and should take into account the identified elicitors and cofactors.

Fatal and Near-Fatal Anaphylaxis: Data From the European Anaphylaxis Registry and National Health Statistics.

BACKGROUND: Anaphylaxis is a serious systemic reaction-data on fatal and near-fatal reactions are limited. OBJECTIVE: To better understand clinical patterns and risks factors of severe anaphylaxis by a deep analysis of data from fatal and near-fatal anaphylaxis. METHODS: Data from the European Anaphylaxis Registry on fatal/near-fatal anaphylactic reactions and national data on anaphylaxis fatalities were investigated. RESULTS: A total of 305 fatal/near-fatal reactions among children and adults including 35 fatalities from the European Anaphylaxis Registry were identified. The most frequent elicitors were drugs, insects, and food. Male patients (66%/60%) were more frequently affected. Male sex, higher age, concomitant mastocytosis, and cardiovascular disease were associated with a more severe outcome. With increasing reaction severity, skin symptoms were less frequently observed (45% of fatal reactions). In parallel, anaphylaxis mortality rates were studied. The data show that anaphylaxis mortality rates increased in Germany from 0.48 (2009) to 0.59 per 1,000,000 population per year (2020). This increase was apparent only in the female population. In this data set, drugs were the most frequent elicitor of anaphylaxis fatalities, and the rate for this increased over time. CONCLUSIONS: We identified not only elicitors but also individual factors to be associated with an increased risk of fatal anaphylaxis. Such patients should be recognized and managed with great caution. The increase in drug-induced fatalities points to the need for a better allergological care of patients suffering from drug hypersensitivity.

Tolerance induction through early feeding to prevent food allergy in infants and children with sensitization against food allergens (TIFFANI): rationale, study design, and methods of a randomized controlled trial.

BACKGROUND: Children with sensitization against foods have to be orally food-challenged before eating these foods for the first time. However, the waiting time for an oral food challenge (OFC) in Germany is about 3-6 months. In contrast, there are hints that an early introduction of allergenic foods might be protective regarding the development of food allergy. The aim of this clinical trial is therefore to investigate, whether an introduction and regular consumption of small amounts of food allergens is safe and will result in an increase of tolerance in children with sensitization against food allergens with unknown clinical relevance. METHODS: In this randomized, placebo-controlled, double-blind, single-center trial, 138 children (8 months to 4 years of age) sensitized to the target allergen(s) hen's egg, cow's milk, peanuts, and/or hazelnuts with unknown clinical relevance will be randomized in a 1:1 ratio to either an active or a placebo group, daily receiving a rusk-like biscuit powder with or without the target allergen(s) for 3-6 months until an OFC will be performed in routine diagnostics. The primary endpoint is an IgE-mediated food allergy to the primary target allergen, after the interventional period. DISCUSSION: Children with sensitization against food allergens with unknown clinical relevance often have to avoid the corresponding foods for several months until an OFC is performed. Therefore, the "window of opportunity" for an early preventive introduction of allergenic foods might be missed. This trial will assess whether an introduction of small allergen amounts will favor tolerance development in these children. TRIAL REGISTRATION: German Clinical Trials Register DRKS00032769. Registered on 02 October 2023.

Age- and Elicitor-Dependent Characterization of Hymenoptera Venom-Induced Anaphylaxis in Children and Adolescents.

BACKGROUND: Hymenoptera venom is one of the most frequent causes of anaphylaxis. Studies from adults indicate the clinical profiles and risk factors of Hymenoptera venom-induced anaphylaxis (VIA). Much less is known about pediatric VIA. OBJECTIVE: To understand elicitor- and age-related factors determining pediatric VIA by analyzing data from the anaphylaxis registry. METHODS: We selected pediatric VIA, pediatric food-induced anaphylaxis (FIA), and adult VIA cohorts from the anaphylaxis registry and performed a comparative data analysis regarding elicitors, symptoms, and management. RESULTS: We identified 725 pediatric patients with VIA, 3,149 with pediatric FIA, and 5,534 with adult VIA. In pediatric VIA, boys were more frequently affected, atopy was not increased, and the onset of the reaction after exposure was fast (≤30 min; 91%) compared with pediatric FIA. Symptoms in pediatric VIA were age dependent, and although respiratory symptoms occurred most frequently besides skin symptoms in both pediatric patients with VIA and FIA, cardiovascular symptoms were more frequently reported in pediatric patients with VIA than pediatric patients with FIA. The analysis of pediatric versus adult VIA revealed clear differences in the frequency of involved organ systems (skin: 93% vs 78%; respiratory: 77% vs 64%; and cardiovascular: 61% vs 85%). For both pediatric and adult VIA, the rates of adrenaline application by a professional were low (29% vs 31%) but hospitalization rates were higher in children than in adults (61% vs 42%). Venom immunotherapy was frequently initiated regardless of age (78% each). CONCLUSIONS: Pediatric VIA is more frequent in boys, symptoms are age dependent, and hospitalization is often required. Adrenaline should be applied according to current guidelines. Venom immunotherapy is an important treatment option in pediatric VIA and should be considered in severely affected children.

Soluble IgE-binding factors in the serum of food-allergic patients: Possible pathophysiological role of soluble FcεRI as protective factor.

BACKGROUND: IgE-mediated food allergy is the result of an aberrant immune response involving the interaction of a food allergen with its specific IgE bound to FcɛRI, the high affinity IgE receptor, on mast cells. Allergen-specific IgE also binds to soluble binding factors, but, their expression and role in food allergy is not well characterized. Here, we assess the prevalence and relevance of soluble IgE binding factors in food allergy and tolerance. METHODS: We measured serum levels of four IgE binding factors, that is, galectin-3, galectin-9, soluble FcɛRI (sFcεRI) and soluble CD23 (sCD23) in 67 adults sensitized to peanut or hazelnut and sFcɛRI in 29 children sensitized to hen's egg. Adults without food allergen sensitization (n = 17) served as healthy controls. We compared serum levels of patients and controls and assessed them, in the former, for links to clinical features including allergy and tolerance. RESULTS: Serum levels of sFcɛRI and sCD23, but not galectin-3 and galectin-9, significantly differ in food-sensitized patients as compared to healthy controls. A subgroup (28%) of peanut and hazelnut allergic patients had elevated sFcεRI levels, that were associated with higher total and specific IgE levels. Furthermore, sFcεRI levels were significantly higher in tolerant subjects compared to allergics. Among hazelnut allergic patients, those with high sFcεRI levels tolerated the highest protein amounts in the oral food challenge. CONCLUSION: sFcɛRI but not sCD23, galectin-3 and galectin-9 might play a role in the pathophysiology of food allergy. Its functional role or use as biomarker should be assessed in further studies.

Vegan diets from an allergy point of view - Position paper of the DGAKI working group on food allergy.

Vegan diets are currently attracting a great deal of attention. However, avoiding animal-based foods restricts the diet and is associated with risks, the extent and medical implications of which are at present not sufficiently understood. Elimination diets represent the usual therapeutic long-term management in the presence of food allergy. In order to understand the risks of vegan diets and to discuss these critically from the perspective of food allergies, the expertise of a nutritionist/dietitian with expertise in this area is indispensable. This position paper deals with the incentives behind and the benefits of a plant-based diet. The knowledge required to cover macro- and micronutrient dietary requirements is presented. Using the avoidance of cow's milk as an example, the challenges of adequately meeting nutritional needs are identified and (so-called) milk alternatives are evaluated from an allergy and nutritional point of view. Finally, other plant-based (substitute) products are evaluated from the same perspective, as significant protein sources in vegan diets (e.g., legumes, nuts, and seeds) are at the same time potential and potent triggers of allergic reactions. However, the allergic potential of many substitute products cannot be fully assessed at present due to gaps in research. Wheat as the most important trigger for anaphylaxis in adults is also evaluated. Finally, the increase in ultra-processed products in the (vegan) food sector and their potential consequences for the immune system are discussed.

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

BACKGROUND: Cow's milk (CM) and hen's egg (HE) are leading triggers of anaphylaxis in early childhood. The aim of this study was to identify clinical phenotypes and therapeutic measures for CM anaphylaxis (CMA) compared to HE anaphylaxis (HEA) in children up to 12 years of age, based on a large pan-European dataset from the European Anaphylaxis Registry. METHODS: Data from 2007 to 2020 on clinical phenotypes and treatment from 10 European countries, as well as Brazil, were analysed. The two-step cluster analysis was used to identify the most frequent phenotypes. For each trigger, three clusters were extracted based on sex, age, and existence of symptoms in four vitally important systems. RESULTS: Altogether 284 children with CMA and 200 children with HEA were identified. They were characterised as male (69% vs. 64%), infants (65% vs. 61%), with a most frequent grade III of Ring&Messmer classification (62% vs. 64%), in CMA versus HEA, respectively. Respiratory symptoms occurred more often in CMA (91% vs. 83%, p = 0.010), especially in infants (89% vs. 79%, p = 0.008). Cardiovascular symptoms were less frequent in CMA (30% vs. 44%, p = 0.002), in both infants (33% vs. 46%, p = 0.027), and older children (25% vs. 42%, p = 0.021). The clusters extracted in the CMA group were characterised as: (1) mild dermal infants with severe GI (40%), 2. severe dermal (35%), 3. respiratory (25%). While in HEA group: 1. infants with severe GI and/or reduction of alertness (40%), (2) conjunctival (16%), (3) mild GI without conjunctivitis (44%). The severity of the reaction was independent from the amount of ingested allergen protein, regardless of trigger. The first-line adrenaline application differed between the countries (0%-92%, as well as the reasons for not administering adrenaline, p < 0.001). CONCLUSIONS: Despite the similarity of their age, sex, and severity grade, the clinical profiles differed between the CMA and HEA children. Adrenaline was underused, and its administration was country dependent. Further studies are needed to assess to what extent the differences in the clinical profiles are related to matrix and/or absorption effects, and/or the allergen itself.