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

Pre-hospital treatment of bee and wasp induced anaphylactic reactions: a retrospective study

Background

Bee and wasp stings are among the most common triggers of anaphylaxis in adults representing around 20% of fatal anaphylaxis from any cause. Data of pre-hospital treatment of bee and wasp induced anaphylactic reactions are sparse. This study aimed to estimate the incidence of bee and wasp induced anaphylactic reactions, the severity of the reactions and to correlate the pre-hospital treatment with the severity of the anaphylactic reaction.

Methods

Retrospective and descriptive study based on data from the Mobile Emergency Care Units (MECUs) in the Region of Southern Denmark (2008 only for Odense and 2009–2014 for the whole region). Discharge summaries with diagnosis related to anaphylaxis according to the International Classification of Diseases 10 (ICD-10) were reviewed to identify bee and wasp induced anaphylactic reactions. The severity of the anaphylactic reaction was assessed according to Sampson’s severity score and Mueller’s severity score. Treatment was evaluated in relation to administration of adrenaline, glucocorticoids and antihistamine.

Results

We identified 273 cases (Odense 2008 n = 14 and Region of Southern Denmark 2009–2014 n = 259) of bee and wasp induced anaphylaxis. The Incidence Rate was estimated to 35.8 cases per 1,000,000 person year (95% CI 25.9–48.2) in the Region of Southern Denmark during 2009–2014. According to Sampson’s severity score, 65% (n = 177) of the cases were graded as moderate to severe anaphylaxis (grade 3–5). Almost one third of cases could not be graded according to Mueller’s severity score. Adrenaline was administrated in 54% (96/177) of cases with moderate to severe anaphylaxis according to Sampson’s severity score, compared to 88% receiving intravenous glucocorticoids (p < 0.001) and 91% receiving intravenous antihistamines (p < 0.001). Even in severe anaphylaxis (grade 5) adrenaline was administered in only 80% of the cases.

Conclusion

Treatment with adrenaline is not administered in accordance with international guidelines. However, making an assessment of the severity of the anaphylactic reaction is difficult in retrospective studies.

Trends, characteristics, and incidence of anaphylaxis in 2001-2010: A population-based study

BACKGROUND

Anaphylaxis is a potentially life-threatening systemic allergic reaction.

OBJECTIVE

We aimed to determine the incidence rate and causes of anaphylaxis during a 10-year period in Olmsted County, Minnesota.

METHODS

Using the resources of the Rochester Epidemiology Project, a comprehensive records linkage system, we performed a population-based incidence study in Olmsted County, Minnesota, from 2001 through 2010. All cases with a diagnosis of anaphylactic shock and 20% of cases with related diagnoses were manually reviewed. The relationships of age group, sex, and year of anaphylaxis with incidence rates were assessed by fitting Poisson regression models.

RESULTS

Six hundred thirty-one cases of anaphylaxis were identified. The median age was 31 years (interquartile range, 19-44 years). The overall age- and sex-adjusted incidence rate was 42 (95% CI, 38.7-45.3) per 100,000 person-years. There was a significant increase in the overall incidence of anaphylaxis during the study period, with an average increase of 4.3% per year (P < .001). In addition, there was a 9.8% increase per year in the incidence rate of food-related anaphylaxis. Food-related anaphylaxis was most common in children aged 0 to 9 years, venom-related anaphylaxis was most common in those 20 to 39 years of age, and medication-related anaphylaxis was most common in those 30 to 39 years of age.

CONCLUSION

The overall incidence rate of anaphylaxis was 42 per 100,000 person-years from 2001-2010 in Olmsted County, Minnesota. The incidence of anaphylaxis increased over time, and several inciting triggers were uniquely associated with different age groups.

Decreasing the undernotification of anaphylaxis deaths in Brazil through the International Classification of Diseases (ICD)-11 revision

BACKGROUND

In 2012, an analysis of the Brazilian mortality database demonstrated undernotification of anaphylaxis deaths due, at least in part, to difficult coding under the International Classification of Diseases (ICD)-10. This work triggered a cascade of strategic international actions supported by the Joint Allergy Academies and the ICD World Health Organization (WHO) representatives to update the classifications of allergic disorders for the ICD-11 revision. These efforts have resulted in the construction of the new 'Allergic and hypersensitivity conditions' section under the 'Disorders of the Immune system' chapter.

OBJECTIVE

To analyze the capacity of the new ICD-11 revision to capture anaphylaxis deaths.

METHODS

We re-estimated the anaphylaxis deaths that occurred in Brazil during the period 2008 to 2010, utilizing this new framework and the database of the Brazilian mortality information system that had initially been extracted in May 2011. However, in 2016, a manual review of each of the 3638 records was performed.

RESULTS

We identified 639 anaphylaxis deaths, of which 95% were classified as 'definitive anaphylaxis deaths'. In contrast to the 2012 published data, we found a higher number of cases; moreover, all 606 definitive anaphylaxis deaths would be considered as underlying causes of death utilizing the ICD-11 revision.

CONCLUSION

This study is the first example of how the new 'Allergic and hypersensitivity conditions' section of the forthcoming ICD-11 can improve the quality of official vital statistics data and the visibility of an important public health concern. This research will facilitate comprehensive, comparable population-based epidemiologic data collection on anaphylaxis.

Medical certification reduces the number of children requiring allergen elimination diets for school lunches

Background

Following the increase in the number of children with food allergies, support systems are now required for school lunches, but a large-scale factual investigation has not been carried out.

Objective

We evaluated the features of elimination diet due to food allergy and the support system in kindergartens and schools.

Methods

A prefecture-based questionnaire survey regarding measures for food allergies in school lunches of all kindergartens, public elementary schools, and public junior high schools (631 facilities) was conducted in Oita Prefecture, Japan.

Results

The recovery rate of the questionnaire was 99.5%, which included 106,008 students in total. A total of 1,562 children (1.5%) required elimination diets. The rate of children on elimination diets in kindergartens and elementary/junior high schools that required medical certification by a physician was 1.2% (324 among 27,761 children), which was significantly lower than the 1.8% of children (1,227 among 68,576 students) on elimination diets at the request of guardians without the need for medical certification (p < 0.0001). A total of 43.9% of the kindergartens and schools said that they would contact guardians if symptoms were observed after accidental ingestion, while a low 8.1% stated that they provided support to children themselves, including the administration of adrenaline auto-injectors.

Conclusion

Medical certification reduces the number of children requiring elimination diets, but it has not been adequately implemented. Furthermore, waiting to contact guardians after symptoms are observed may lead to the delayed treatment of anaphylaxis. Cooperation between physicians and teachers is desired to avoid the overdiagnosis and undertreatment of children with food allergies.

Efficacy of a Novel Prefilled, Single-Use, Needle-Free Device (Zeneo®) in Achieving Intramuscular Agent Delivery: An Observational Study

BACKGROUND

It is recognized that, as a result of variation in tissue anatomy, current auto-injectors may have insufficient needle length to achieve successful intramuscular agent delivery in a number of patients. The Zeneo^® auto-injector is a novel prefilled, single-use, needle-free device currently in development for intradermal, subcutaneous, and intramuscular agent delivery across a variety of clinical indications. We aimed to evaluate delivery depth of the device calibrated at pressure appropriate for intramuscular (IM) administration.

METHODS

This was a prospective single-center study in healthy adult volunteers, in whom each received a single injection of saline into the anterolateral thigh. Using sequential MRI scans, we measured skin-to-muscle distance (STMD) agent delivery depth, and the success of IM agent penetration. Device dynamic pressure measurements were also recorded.

RESULTS

Results are reported for 37 subjects with evaluable MRI scans; 19 men, 18 women; mean age 38 years (range 20-58); mean BMI 27.0 kg/m² (range 21.2-30.8 kg/m²). Mean STMD values were 18.6 mm (range 13.4-23.6 mm) in women and 10.0 mm (range 5.0-21.7 mm) in men, with gender differences due primarily to greater subcutaneous thickness in women. A trend for greater STMD in subjects with BMI greater than 25 kg/m² was seen. Mean injectate penetration depths of 30.1 mm (range 20.2-45.6 mm) were observed with values similar in male and female subjects. Successful IM delivery was reported in 95% of subjects. When failure occurred, this was not due to inadequate injection depth. Device pressure (P _max) had the greatest influence on injectate muscle penetration.

CONCLUSION

Use of the Zeneo^® auto-injector achieves delivery depth that ensures intramuscular delivery in both men and women, regardless of BMI. Consistent with other reported data, STMD is greater in women.

FUNDING

Crossject.

How should occupational anaphylaxis be investigated and managed?

PURPOSE OF REVIEW

Anaphylaxis is a systemic allergic reaction that can be life-threatening or fatal and can result from work-related exposures. This review study focuses on the assessment, main triggers, and management of occupational anaphylaxis.

RECENT FINDINGS

Exposed workers can be sensitized through inhalation and skin contact, and the risks increase with penetration of the allergen through the skin. The main eliciting agents of occupational anaphylaxis include stinging insects and animal bites, natural rubber latex and other vegetable allergens, food products, and drugs. Workers sensitized to occupational allergens may also develop anaphylaxis outside the work environment from exposure to the same or to cross-reacting allergens. Cofactors at work such as exercise may increase the risk. The relevant medical records and laboratory tests (e.g. tryptase) performed during the episode should be reviewed.

SUMMARY

It is very important to confirm the diagnosis and to identify the specific trigger of anaphylaxis. Component-resolved diagnosis may help in the identification of primary sensitizers or cross-reactive allergens. Adrenaline must be administered to all patients experiencing anaphylaxis. Removal from exposure is mandatory to prevent further episodes. A written emergency management plan, health and safety education, and training and surveillance should be enforced in occupations at greater risk.

The role and choice criteria of antihistamines in allergy management - expert opinion

Allergic diseases are the most common chronic conditions lasting throughout the patient’s life. They not only cause significant deterioration in the quality of life of patients but also lead to significant absenteeism and reduced productivity, resulting in very high costs for society. Effective and safe treatment of allergic diseases is therefore one of the main challenges for public health and should be carried out by all the specialists in family medicine, internists and paediatricians in collaboration with allergists, otorhinolaryngologists and dermatologists. Antihistamines are most commonly used in the treatment of allergies. Several dozen drugs are available on the pharmaceutical market, and their generic forms are advertised widely as very effective drugs for the treatment of allergic diseases. What is the truth? What are the data from clinical trials and observational studies? Are all drugs equally effective and safe for the patient? According to a panel of experts representing various fields of medicine, inappropriate treatment of allergies can be very risky for patients, and seemingly equally acting medications may differ greatly. Therefore, a panel of experts gathered the latest data from the entire scientific literature and analysed the latest standards and recommendations prepared by scientific societies. This paper provides a summary of these studies and highlights the importance for the patient of the proper choice of drug to treat his allergies.

Use of Food Allergy Panels by Pediatric Care Providers Compared With Allergists

BACKGROUND AND OBJECTIVE

Immunoglobullin E (IgE)-mediated food allergies affect 5% to 8% of children. Serum IgE levels assist in diagnosing food allergies but have low positive predictive value. This can lead to misinterpretation, overdiagnosis, and unnecessary dietary elimination. Use of IgE food allergen panels has been associated with increased cost and burden. The scale of use of these panels has not been reported in the medical literature.

METHODS

We conducted a retrospective review of a commercial laboratory database associated with a tertiary care pediatric academic medical center for food IgE tests ordered by all provider types during 2013.

RESULTS

A total of 10 794 single-food IgE tests and 3065 allergen panels were ordered. Allergists ordered the majority of single-food IgE tests (58.2%) whereas 78.8% of food allergen panels were ordered by primary care providers (PCPs) (P < .001). Of all IgE tests ordered by PCPs, 45.1% were panels compared with 1.2% of orders placed by allergists (P < .001). PCPs in practice for >15 years ordered a higher number of food allergen panels (P < .05) compared with PCPs with less experience. Compared with allergists, PCPs ordered more tests for unlikely causes of food allergies (P < .001). Total cost of IgE testing and cost per patient were higher for PCPs compared with allergists.

CONCLUSIONS

Review of food allergen IgE testing through a high volume outpatient laboratory revealed PCPs order significantly more food allergen panels, tests for uncommon causes of food allergy, and generate higher cost per patient compared with allergists. These results suggest a need for increased education of PCPs regarding proper use of food IgE tests.

Prevention of Anaphylaxis: The Role of the Epinephrine Auto-Injector

Anaphylaxis is a life-threatening condition, with at-risk individuals remaining at chronic high risk of recurrence. Anaphylaxis is frequently underrecognized and undertreated by healthcare providers. The first-line pharmacologic intervention for anaphylaxis is epinephrine, and guidelines uniformly agree that its prompt administration is vital to prevent progression, improve patient outcomes, and reduce hospitalizations and fatalities. Healthcare costs potentially associated with failure to provide epinephrine (hospitalizations and emergency department visits) generally exceed those of its provision. At-risk patients are prescribed epinephrine auto-injectors to facilitate timely administration in the event of an anaphylactic episode. Despite guideline recommendations that patients carry 2 auto-injectors at all times, a significant proportion of patients fail to do so, with cost of medicine cited as one reason for this lack of adherence. With the increase of high-deductible healthcare plans, patient adherence to recommendations may be further affected by increased cost sharing. The recognition and classification of epinephrine as a preventive medicine by both the US Preventive Services Task Force and insurers could increase patient access, improve outcomes, and save lives.

Diagnosis of exercise-induced anaphylaxis: current insights

Exercise-induced anaphylaxis (EIAn) is defined as the occurrence of anaphylactic symptoms (skin, respiratory, gastrointestinal, and cardiovascular symptoms) after physical activity. In about a third of cases, cofactors, such as food intake, temperature (warm or cold), and drugs (especially nonsteroidal anti-inflammatory drugs) can be identified. When the associated cofactor is food ingestion, the correct diagnosis is food-dependent EIAn (FDEIAn). The literature describes numerous reports of FDEIAn after intake of very different foods, from vegetables and nuts to meats and seafood. One of the best-characterized types of FDEIAn is that due to ω5-gliadin of wheat, though cases of FDEIAn after wheat ingestion by sensitization to wheat lipid transfer protien (LTP) are described. Some pathophysiological mechanisms underlying EIAn have been hypothesized, such as increase/alteration in gastrointestinal permeability, alteration of tissue transglutaminase promoting IgE cross-linking, enhanced expression of cytokines, redistribution of blood during physical exercise leading to altered mast-cell degranulation, and also changes in the acid–base balance. Nevertheless, until now, none of these hypotheses has been validated. The diagnosis of EIAn and FDEIAn is achieved by means of a challenge, with physical exercise alone for EIAn, and with the assumption of the suspected food followed by physical exercise for FDEIAn; in cases of doubtful results, a double-blind placebo-controlled combined food–exercise challenge should be performed. The prevention of this particular kind of anaphylaxis is the avoidance of the specific trigger, ie, physical exercise for EIAn, the assumption of the culprit food before exercise for FDEIAn, and in general the avoidance of the recognized cofactors. Patients must be supplied with an epinephrine autoinjector, as epinephrine has been clearly recognized as the first-line intervention for anaphylaxis.

Pearls and Pitfalls in Diagnosing IgE-Mediated Food Allergy

The term "food allergy" is used by many patients and clinicians to describe a range of symptoms that occur after ingestion of specific foods. However, not all symptoms occurring after food exposure are due to an allergic, or immunologic, response. It is important to properly evaluate and diagnose immunoglobulin E (IgE)-mediated food allergy as this results in reproducible, immediate onset, allergic reactions that can progress toward life-threatening anaphylaxis. Proper diagnosis requires understanding of the common foods that cause these reactions in addition to key historical elements such as symptoms, timing and duration of reaction, and risk factors that may predispose to development of IgE-mediated food allergy. Diagnostic testing for food-specific IgE can greatly aid the diagnosis. However, false-positive test results are very common and can lead to overinterpretation, misdiagnosis, and unnecessary dietary elimination. This review discusses important aspects to consider during evaluation of a patient for suspected IgE-mediated food allergy.

Supporting the validation of the new allergic and hypersensitivity conditions section of the World Health Organization International Classification of Diseases-11

Background

The new International Classification of Diseases (ICD)-11 "Allergic and hypersensitivity conditions" section has been constructed as a result of a detailed and careful action plan based on scientific evidences for the necessity of changes and collaboration with the World Health Organization (WHO) ICD-11 revision governance. All the efforts are being acknowledged by the Joint Allergy Academies.

Objective

Considering the new classification model addressed to the allergic and hypersensitivity conditions and following the ICD WHO agenda, we believe it is the appropriate time to start supporting the validation process in collaboration with the WHO ICD governance.

Methods

We conducted a mapping of ICD-10 allergic and hypersensitivity conditions in the ICD-11 beta phase structure and categorized the conditions as fitting by "precoordination," "postcoordination," "indexed to the ICD-11 Foundation," "no code fit properly" or "no correspondence" in the ICD-11.

Results

From overall 125 ICD-10 entities spread in 6 chapters, 57.6% were able to be precoordinated, 4% postcoordinated, 12% indexed to the Foundation, 9.6% had no code fitting properly and 18.6% had no correspondence in the ICD-11 framework.

Conclusion

We have been able to demonstrate that 83.2% of the ICD-10 allergic and hypersensitivity conditions could be captured by the current ICD-11 beta draft framework. We strongly believe that our findings constitute a key step forward for a softer transition of the ICD-10 allergic and hypersensitivity conditions to the ICD-11, supporting the WHO in this process as well as strengthening the visibility of the Allergy specialty and ensuring quality management of allergic patients.

Anaphylaxis Knowledge Among Pediatric Intensivists in Brazil: A Multicenter Survey

OBJECTIVE

To assess the knowledge and practice preferences of anaphylaxis treatment among pediatric intensivists in 5 Brazilian pediatric intensive care unit (PICU) settings.

STUDY DESIGN

The cohort was a cross-sectional sample from 5 PICUs; a 7-question survey was personally applied to participants regarding their professional clinical experience and the first-line drug choices when treating an anaphylaxis episode.

RESULTS

Of 43 participant physicians, the majority (83.8%) correctly identified epinephrine as the treatment of choice for anaphylaxis, yet only 41.9% chooses the intramuscular route of administration.

CONCLUSION

This study shows that the knowledge of anaphylaxis treatment is deficient among pediatric intensivists in Brazil. The dissemination of recent World Allergy Organization guidelines on anaphylaxis should be encouraged.

Anaphylaxis in children

PURPOSE OF REVIEW

Anaphylaxis is a serious allergic reaction that can be life threatening. We will review the most recent evidence regarding the diagnosis, treatment, monitoring, and prevention of anaphylaxis in children.

RECENT FINDINGS

Histamine and tryptase are not sufficiently accurate for the routine diagnosis of anaphylaxis, so providers should continue to rely on clinical signs. Platelet-activating factor shows some promise in the diagnosis of anaphylaxis. Intramuscular is the best route for epinephrine administration for children of all weights. Glucocorticoids may reduce prolonged hospitalizations for anaphylaxis. Children with anaphylaxis who have resolving symptoms and no history of asthma or previous biphasic reactions may be observed for as few as 3-4 h before emergency department discharge. Early peanut introduction reduces the risk of peanut allergy.

SUMMARY

Epinephrine remains the mainstay of anaphylaxis treatment, and adjuvant medications should not be used in its place. All patients with anaphylaxis should be prescribed and trained to use an epinephrine autoinjector. Clinically important biphasic reactions are rare. Observation in the emergency department for most anaphylaxis patients is recommended, with the duration determined by risk factors. Admission is reserved for patients with unimproved or worsening symptoms, or prior biphasic reaction.

Anaphylaxis Imaging: Non-Invasive Measurement of Surface Body Temperature and Physical Activity in Small Animals

In highly sensitized patients, the encounter with a specific allergen from food, insect stings or medications may rapidly induce systemic anaphylaxis with potentially lethal symptoms. Countless animal models of anaphylaxis, most often in BALB/c mice, were established to understand the pathophysiology and to prove the safety of different treatments. The most common symptoms during anaphylactic shock are drop of body temperature and reduced physical activity. To refine, improve and objectify the currently applied manual monitoring methods, we developed an imaging method for the automated, non-invasive measurement of the whole-body surface temperature and, at the same time, of the horizontal and vertical movement activity of small animals. We tested the anaphylaxis imaging in three in vivo allergy mouse models for i) milk allergy, ii) peanut allergy and iii) egg allergy. These proof-of-principle experiments suggest that the imaging technology represents a reliable non-invasive method for the objective monitoring of small animals during anaphylaxis over time. We propose that the method will be useful for monitoring diseases associated with both, changes in body temperature and in physical behaviour.