Elicitors of severe allergic reactions - reports from allergists and emergency doctors.

Data from the anaphylaxis registry of German-speaking countries indicate that food is the most frequent elicitor of severe allergic reactions in children, insect venom is the most frequent elicitor in adults. The anaphylaxis registry considers data from patients of allergy centers. The aim of the present study was to collect data regarding elicitors, cofactors and the medical care of patients with severe allergic reactions seen by private practice allergists but also patients seen by emergency doctors. From June 2008 to December 2009 70 cases of severe allergic reactions from private practice allergists and 154 from emergency doctors in Berlin were registered. Our data show that the profile of elicitors differs among the reporting groups. The reported causes from allergists were severe reactions to food, insect venom and subcutaneous immunotherapy, the emergency doctors reported insect venom as the most frequent elicitor. Our data show that a systematic evaluation of severe allergic reactions can provide important data about elicitors and circumstances of anaphylaxis. Through a comparison with data from the anaphylaxis registry the analysis of the data from the emergency doctors will allow to determine how many patients with severe allergic reactions are seen by an allergist for further diagnostic work-up and subsequent therapy.

Food-induced anaphylaxis and cofactors - data from the anaphylaxis registry.

Food allergens are frequent causes of anaphylaxis. In particular in children and adolescents they are the most frequent elicitors of severe allergic reactions, and in adults food allergens rank third behind insect venom and drugs. Since July 2006 severe allergic reactions from Germany, Austria, and Switzerland are collected in the anaphylaxis registry. Currently 78 hospitals and private practises are connected. From July 2006 until February 2009 1,156 severe allergic reactions were registered. Among children and adolescents (n = 187, age range from 3 months to 17 years) food allergens were the most frequent triggers, comprising 58% of cases. In the adult group (n = 968, 18 - 85 years) food allergens were in the third position (16.3%) behind insect venom and drugs. In children legumes (31%) and in particular peanuts were frequently responsible food allergens, followed by tree nuts (25%) with hazelnut being the most frequent elicitor. In adults fruits (13.4%) most often induced severe food-dependent anaphylaxis, but also animal products (12.2%); among these most frequently crustaceans and molluscs. Cofactors were often suspected in food-dependent anaphylaxis, namely in 39% of the adult group and in 14% of the pediatric group. In adults drugs (22%) and physical activity (10%) were reported to be the most frequent cofactors, in children physical activity was suspected in 8.7% and drugs in 2.6%. Concomitant diseases like atopic dermatitis, allergic asthma, or allergic rhinoconjunctivitis were reported in 78% of children and adolescents and in 67% of the adults. In conclusion, food-induced anaphylaxis, its cofactors and concomitant diseases are age-dependent. The data offers to identify risk factors of anaphylaxis.

[Exercise-induced anaphylaxis]. / Anstrengungsinduzierte Anaphylaxie.

Exercise-induced anaphylaxis is a mast cell dependent reaction, which is induced by allergen exposure in combination with physical activity. Typically, the reaction occurs within 2 hours after allergen exposure followed by physical activity. Not only food allergens but all kinds of allergens including drugs can induce this form of anaphylaxis. The clinical symptoms of exercise-induced anaphylaxis are the same as in any other type of anaphylaxis. Thus not only the skin and mucosa but also other organ systems like the lungs, cardiovascular system and gastrointestinal tract can be affected. The diagnostic work up should cover a detailed clinical history including the assessment of symptoms and possible trigger factors including suspected allergens. Besides classical allergy diagnostics like skin prick tests and specific IgE determination, tryptase should be measured for the differential diagnosis to exclude mast cell dependent diseases. The diagnosis of exercise-induced anaphylaxis is made by the means of a double-blind placebo-controlled provocation test. Both, a sufficient amount of allergen and of physical activity must be achieved for a valid test. After the diagnosis is made, patients should be extensively counseled and provided with an emergency kit including an epinephrine auto injector.

Anaphylaxis in an emergency setting - elicitors, therapy and incidence of severe allergic reactions.

BACKGROUND: Anaphylaxis is a severe potentially life-threatening hypersensitivity reaction with an estimated lifetime prevalence of 0.5-2.0%. The prevalence and incidence of anaphylactic reactions in Germany are unknown. We therefore assessed anaphylactic patients seen by emergency physicians in the Berlin area covering 4 million people. METHODS: A standardised questionnaire was filled from 2008 to 2010 by the emergency physicians. RESULTS: A total of 333 cases of anaphylaxis were reported. 295 of these met the inclusion criteria for severity and were analysed. 13.9% (n = 41) were reactions with respiratory symptoms, 25.4% (n = 75) with cardiovascular, and in 60.7% (n = 179) of cases, respiratory and cardiovascular symptoms were reported. Two reactions were fatal. The most common elicitors were food products (32.2%), drugs (29.2%) and insect venom (19.3%). The most frequently given drugs were corticoids and antihistamines, but not adrenaline. For 2008, the calculated incidence was 4.5 per 100 000. CONCLUSIONS: Our data show that food products are frequent elicitors of severe allergic reactions in the general population including children and adults. It unravels a strong underuse of adrenaline by emergency physicians, not reflecting treatment protocols according to the current guidelines. As data obtained from allergists reveal a different rank order of elicitors, this study suggests that food-allergic adult patients may present a risk population and should receive more attention by allergists.

[Food-associated anaphylaxis. Data from the anaphylaxis registry]. / Nahrungsmittelassoziierte Anaphylaxie. Daten aus dem Anaphylaxie-Register.

Severe allergic reactions are reported to the anaphylaxis registry in German-speaking countries. The data provides knowledge regarding the diagnosis and management of patients suffering from anaphylaxis. The ranking of the most frequent elicitors inducing anaphylaxis is age-dependent and also influenced by the group which is reporting the data. The list of food allergens inducing anaphylaxis also varies with age. In children and adolescents peanuts are common elicitors of food-dependent anaphylaxis: in adults wheat is the most frequent cause. Furthermore, the data from the anaphylaxis registry provides information about rare triggers, as well as alerting us to those causative agents which are increasing in frequency. The relevance of augmentation factors is most likely age-dependent, whereas co-morbidities including atopic diseases like atopic dermatitis and allergic asthma occur frequently in children suffering from food-dependent anaphylaxis. The present manuscript provides data on food allergens such as peas and cauliflower, which have been reported as rare causes of anaphylaxis.

[The registry for severe allergic reactions in German-speaking countries. Recent data and perspectives]. / Das deutschsprachige Anaphylaxie-Register. Aktueller Stand und Perspektiven.

The anaphylaxis registry collects data from patients with severe allergic reactions via an online questionnaire. Currently 85 centers from Germany, Austria, and Switzerland are involved. The data are entered by allergists. They cover demographical data, data of the elicitors, concomitant diseases, circumstances of the allergic reactions, and information about the treatment of affected patients. Until to date the data show that the elicitor profile of severe allergic reactions depends on the age of patients. In childhood, food allergens are the most frequent elicitors, whereas in adults insect stings are most frequently the cause of anaphylaxis. The analysis of concomitant diseases suggests that allergic diseases like allergic asthma, allergic rhinitis or atopic dermatitis occur frequently in children with anaphylaxis, whereas in adults cardiovascular diseases predominate. The data about the medical treatment of affected patients show that antihistamines and corticosteroids are often used in German-speaking countries for the treatment of severe allergic reactions, whereas adrenaline, the drug of choice, is only rarely used (< 20%). The registry is an important clinical epidemiological tool which allows to generate research but also disease management-related questions.

Symptom profile and risk factors of anaphylaxis in Central Europe.

BACKGROUND: Anaphylaxis is the most severe manifestation of an IgE-dependent allergy. Standardized acquired clinical data from large cohorts of well-defined cases are not available. The aim of this study was to analyse the symptom profile and risk factors of anaphylaxis in a large Central European cohort. METHODS: We acquired data from patients in Germany, Austria and Switzerland who experienced a severe allergic reaction defined by the onset of severe pulmonary and/or severe cardiovascular symptoms. The data were gained via an online questionnaire from 83 medical centres specialized in allergy. Data were collected from 2006 to 2010 and analysed by using a multinomial regression model. RESULTS: A total of 2012 paediatric and adult patients were included into the present analysis. The skin (84%) was the most frequently affected organ followed by the cardiovascular (72%) and the respiratory (68%) system. The regression model analysing the onset of cardiovascular versus respiratory symptoms revealed a strong impact of age (adjusted OR = 6.08; 95% CI, 3.35-11.01; P < 0.001). Furthermore, the elicitor food (adjusted OR = 0.29; 95% CI, 0.21-0.41, P < 0.001) and the presence of atopic diseases (adjusted OR = 0.54; 95% CI, 0.40-0.73, P < 0.001) were significantly associated with the onset of respiratory symptoms. CONCLUSION: Data from individuals who experienced anaphylaxis can support the identification of risk factors. The present study indicates that age, the elicitor itself and the presence of atopic diseases have an impact on the symptom profile of anaphylaxis. Identifying further risk factors of anaphylaxis is of significant importance for clinical practice in the future.

Impact of native, heat-processed and encapsulated hazelnuts on the allergic response in hazelnut-allergic patients.

BACKGROUND: Pollen-associated food allergy is common. However, systemic reactions or even life-threatening anaphylaxis are rare. OBJECTIVE: The aim of this study was to investigate the clinical impact of native, heat-processed and encapsulated hazelnuts (HN) in patients with proven HN allergy. METHODS: One hundred and thirty-two patients with a positive history of HN allergy were recruited. Sensitization was confirmed by a skin prick test (SPT) and sIgE against HN. After an HN-free diet, double-blind placebo-controlled challenges were performed with increasing amounts of native and roasted HN. A subset of patients were given HN capsules to circumvent the oral mucosa. Basophil activation was measured by flow cytometry before and after provocation but also ex vivo using native and roasted HN extracts. RESULTS: Three groups of HN-allergic patients were identified depending on their clinical reaction pattern. The dosages by which allergic reactions were elicitated varied for native HN from 0.01 to 2.0 g, with a median of 0.1 g, for roasted HN from 0.01 to 10.0 g, with a median of 0.23 g, and for encapsulated HN from 0.1 to 3.0 g, with a median of 0.3 g. Accordingly, the SPT was more frequently positive and resulted in greater weal reactions if native HN was used. This finding was confirmed by ex vivo basophil activation showing that significantly higher allergen extract concentrations (roasted>native) were necessary to induce 50% basophil activation. CONCLUSION: Our data show that heat processing of HN reduces its allergenicity. SPT but also the basophil activation test can be used to determine the reactivity of an allergen extract.