An update on epidemiology of anaphylaxis in children and adults

Excretory/Secretory Products from Schistosoma japonicum Eggs Alleviate Ovalbumin-Induced Allergic Airway Inflammation

INTRODUCTION

Excretory/secretory products (ESPs) derived from helminths have been reported to effectively control allergic inflammation, which have better therapeutic prospects than live parasite infections. However, it remains unknown whether ESPs from schistosome eggs can protect against allergies, despite reports alleging that schistosome infection could alleviate disordered allergic inflammation.

METHOD

In the present study, we investigated the protective effects of ESPs from Schistosoma japonicum eggs (ESP-SJE) on asthmatic inflammation. Firstly, we successfully established an allergic airway inflammation model in mice by alum-adjuvanted ovalbumin (OVA) sensitization and challenge. ESP-SJE were administered intraperitoneally on days -1 and 13 (before sensitization), on day 20 (before challenge), and on days 21-24 (challenge phase).

RESULTS

The results showed that ESP-SJE treatment significantly reduced the infiltration of inflammatory cells, especially eosinophils into the lung tissue, inhibited the production of the total and OVA-specific IgE during OVA-sensitized and -challenged phases, respectively, and suppressed the secretion of Th2-type inflammatory cytokines (IL-4). Additionally, ESP-SJE treatment significantly upregulated the regulatory T cells (Tregs) in the lung tissue during OVA challenge. Furthermore, using liquid chromatography-mass spectrometry analysis and Treg induction experiments in vitro, we might identify nine potential therapeutic proteins against allergic inflammation in ESP-SJE. The targets of these candidate proteins included glutathione S-transferase, egg protein CP422 precursor, tubulin alpha-2/alpha-4 chain, actin-2, T-complex protein 1 subunit beta, histone H₄, whey acidic protein core region, and molecular chaperone HtpG.

CONCLUSION

Taken together, the results discussed herein demonstrated that ESP-SJE could significantly alleviate OVA-induced asthmatic inflammation in a murine model, which might be mediated by the upregulation of Treg in lung tissues that may be induced by the potential modulatory proteins. Therefore, potential proteins in ESP-SJE might be the best candidates to be tested for therapeutic application of asthma, thus pointing out to a possible new therapy for allergic airway inflammation.

Lacticaseibacillus rhamnosus: A Suitable Candidate for the Construction of Novel Bioengineered Probiotic Strains for Targeted Pathogen Control

Probiotics, with their associated beneficial effects, have gained popularity for the control of foodborne pathogens. Various sources are explored with the intent to isolate novel robust probiotic strains with a broad range of health benefits due to, among other mechanisms, the production of an array of antimicrobial compounds. One of the shortcomings of these wild-type probiotics is their non-specificity. A pursuit to circumvent this limitation led to the advent of the field of pathobiotechnology. In this discipline, specific pathogen gene(s) are cloned and expressed into a given probiotic to yield a novel pathogen-specific strain. The resultant recombinant probiotic strain will exhibit enhanced species-specific inhibition of the pathogen and its associated infection. Such probiotics are also used as vehicles to deliver therapeutic agents. As fascinating as this approach is, coupled with the availability of numerous probiotics, it brings a challenge with regard to deciding which of the probiotics to use. Nonetheless, it is indisputable that an ideal candidate must fulfil the probiotic selection criteria. This review aims to show how Lacticaseibacillus rhamnosus, a clinically best-studied probiotic, presents as such a candidate. The objective is to spark researchers’ interest to conduct further probiotic-engineering studies using L. rhamnosus, with prospects for the successful development of novel probiotic strains with enhanced beneficial attributes.

Needs Assessment for Eosinophilic Esophagitis Education in School Nurses

Over the past 2 decades, eosinophilic esophagitis (EoE) has become increasingly recognized as a common cause of gastrointestinal morbidity in children. A mainstay of treatment is food avoidance, which must be implemented in both the home and school settings for school-aged children. The aim of this study is to assess school nurses' familiarity with EoE with regard to food avoidance and treatment in the school setting. We conducted a 19-question online survey of 60 school nurses (elementary through high school) recruited from Dauphin, Lebanon, and Lancaster Counties in Pennsylvania. Results indicated that 62% of respondents were familiar with EoE. However, only 22% felt comfortable distinguishing between symptoms of EoE and food-dependent anaphylaxis. Almost all respondents (97%) were interested in learning more about EoE. We report significantly increased familiarity with food-dependent anaphylaxis in comparison with EoE among school nurses. There is an interest and need for increasing education on EoE.

Hymenoptera allergy and anaphylaxis: are warmer temperatures changing the impact?

PURPOSE OF REVIEW

Climate change has brought about many changes in our ecosystem. Prolongation of pollen seasons has been reported, related to earlier frost off in the spring and later onset of frost on in the fall. This review considers recent global evidence that stinging insects are redistributing toward the poles, thereby potentially increasing human exposure and risk of sting events.

RECENT FINDINGS

With changing climate, particularly climate warming, range expansion of insects is occurring in both the Northern and Southern Hemispheres. Likewise, stinging insects, such as Hymenoptera and Lepidoptera, are also expanding range. Though there is scant data on associated increase of insect-related anaphylaxis, increased insect-human interaction is certain.

SUMMARY

It is likely that climate change will continue to alter the distribution and population of Hymenoptera and other insects. As temperatures warm and regions become suitable for nesting and establishment of colonies, many insects will expand their territory. As already reported in Alaska, one would anticipate expansion of range, especially toward the poles, thereby increasing the probability of human encounters and likewise anaphylaxis.

Food allergy promotes a Th2/Th17 response that drives house dust mite-induced allergic airway inflammation in humanized mice

Food allergy is related to increasing risk of the development of allergic asthma, but the precise interplay between sensitization to different allergens in different compartments of the body is not fully understood. The aim of this study was to develop a novel humanized murine model of mixed food and respiratory allergy that recapitulates the human anaphylactic response and to more clearly understand the impact of food allergies on asthma. Immunodeficient mice transferred with peripheral blood mononuclear cells (PBMCs) from donors with peanut and house dust mite (HDM) allergy were exposed and challenged to peanut. Between peanut exposure and challenge, mice were intranasally treated to HDM. Allergic parameters were analyzed. Allergen-specific immunoglobulin (Ig)E in sera could only be measured in mice treated with peripheral blood mononuclear cells (PBMCs) plus allergen. A preceding peanut exposure increased IgE levels, histamine release, bronchial hyper-responsiveness and lung inflammation. Recruitment of inflammatory cells to the airways was aggravated associated with an enhanced T helper type 2 (Th2)/Th17 cytokine secretion when the two allergies were present. A preceding peanut exposure amplifies allergic asthma in this humanized model, which may contribute to the understanding of underlying immunological mechanism of polysensitization occurring in allergic individuals and evaluation of therapeutic interventions.

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.

Changes in Emergency Department Concordance with Guidelines for the Management of Food-Induced Anaphylaxis: 1999-2001 versus 2013-2015

BACKGROUND

Awareness about food allergy and food-induced anaphylaxis (FIA) has increased dramatically over the past decade. It remains unclear, however, whether concordance with guidelines for FIA management has improved over time.

OBJECTIVE

Our objective was to describe changes in emergency department (ED) concordance with guidelines for FIA management.

METHODS

We analyzed data from 2 multicenter retrospective studies of patients with food-related acute allergic reactions seen in 1 of 17 EDs during 2 time periods: 1999 to 2001 and 2013 to 2015. Visits were identified similarly across years-for example, using International Classification of Diseases, Ninth Revision, Clinical Modification codes 693.1, 995.60, 995.61-995.69, 995.0, and 995.3. Anaphylaxis was defined as an acute allergic reaction with involvement of 2+ organ systems or hypotension. We compared concordance between time periods for 4 guideline recommendations: (1) treatment with epinephrine, (2) discharge prescription for an epinephrine autoinjector (EAI), (3) referral to an allergist/immunologist, and (4) instructions to avoid offending allergen.

RESULTS

We compared 290 patients with FIA during 1999 to 2001 and 459 during 2013 to 2015. Any treatment with epinephrine (pre-ED or in the ED) for patients with FIA increased over time (38% vs 56%; P < .001). Prescriptions for EAI at discharge (24% vs 54%; P < .001) and documentation for referral to an allergist/immunologist (14% vs 24%; P = .001) approximately doubled, whereas instructions to avoid the offending allergen did not change significantly (37% vs 43%; P = .08). Receipt of 3+ guideline recommendations remained low but almost quadrupled over the study interval (6% vs 23%; P < .001).

CONCLUSIONS

Over the nearly 15-year study interval, we observed clinically and statistically significant increases in ED concordance with epinephrine-related guidelines for FIA. Management gaps remain and interventions to standardize care still appear warranted.

Anaphylaxis risk factors for hospitalization and intensive care: A comparison between adults and children in an upstate New York emergency department

Background: Anaphylaxis is an acute, systemic allergic reaction that can be life threatening, and with an increasing incidence and costs associated with hospitalization and intensive care. Objective: To assess the risk factors for hospitalization by comparing pediatric and adult patients. Methods: We performed a retrospective chart review for patients with anaphylactic reactions who presented to the Albany Medical Center emergency department between 2005 and 2012. Results: We identified 267 anaphylactic reactions in 258 patients (143 adults). Of those, 128 (48%) were not coded as anaphylaxis despite fulfilling diagnostic criteria. Foods were the most common trigger both in adults and children. Factors associated with increased odds of hospitalization (intensive care unit [ICU] and hospital floor combined) included a severity score of 3 in both children (odds ratio [OR] 41.86 [95% confidence interval {CI}, 2.9-602.48], p = 0.006) and adults (OR 32.52 [95% CI, 6.28-168.35], p < 0.001), and those who received multiple doses of epinephrine in children (OR 15.36 [95% CI, 1.9-121.4], p = 0.009) and adults (OR 11.49 [95% CI, 3.08-44.13], p < 0.001). Patient characteristics associated with ICU admission in children and adults combined included Medicare and/or Medicaid insurance (OR 4.96 [95% CI, 1.14-21.67], p = 0.023), cutaneous symptoms (OR 0.19 [95% CI, 0.04-0.79], p = 0.23), and cardiovascular symptoms (OR 5.8 [95% CI, 1.16-28.87], p = 0.032). Conclusion: Anaphylaxis remains underrecognized and improperly treated in the emergency department. Severity of symptoms and receiving multiple doses of epinephrine were associated with hospitalization in both children and adults. Medicare and/or Medicaid insurance, and cardiovascular or cutaneous symptoms were characteristics associated with ICU admission in our cohort.

The role of regulatory T cells in the acquisition of tolerance to food allergens in children

Food allergy is a pathological immune reaction that identifies certain harmless food proteins, usually tolerated by the majority of the people, as a threat. The prevalence of these food allergies is increasing worldwide and currently affects 8% of children. Exacerbated reactions to milk, egg and peanut are the most frequent in the pediatric population. It is well known that allergic diseases are a type 2 T-helper (Th2) immune response, characterized by the elevated production of IgE antibodies. However, little is known about the immune mechanisms responsible for the development of clinical tolerance toward food allergens. Recent studies have suggested the key role of regulatory T cells (Tregs) in controlling allergic inflammation. In this review, we discuss the importance of Tregs in the pathogenesis of food allergy and the acquisition of oral tolerance in children. Further investigation in this area will be crucial for the identification of predictive markers and the development of new therapies, which will represent a clinical and social benefit for these allergic diseases.

Risk factors and treatment of refractory anaphylaxis - a review of case reports

INTRODUCTION

Patients experiencing anaphylaxis who do not recover after treatment with intramuscular adrenaline are regarded as suffering from refractory anaphylaxis. The incidence of refractory anaphylaxis is estimated to range between 3-5% of anaphylaxis cases. The risk factors for refractory anaphylaxis are unknown. Areas covered: In the present analysis, we aimed to evaluate the management and risk factors of refractory anaphylaxis to highlight possible clinical implications for updating current management algorithms. Expert commentary: According to international guidelines, adrenaline given through the intramuscular (i.m.) route is a rapid and safe treatment but may be insufficient. Therefore, defined standardized treatment protocols for such cases of refractory anaphylaxis are needed to optimize the treatment. Point-of-care diagnostics may enable doctors to identify patients experiencing severe, refractory anaphylaxis early in order to initiate intensified critical care treatment.

Hookworm recombinant protein promotes regulatory T cell responses that suppress experimental asthma

In the developed world, declining prevalence of some parasitic infections correlates with increased incidence of allergic and autoimmune disorders. Moreover, experimental human infection with some parasitic worms confers protection against inflammatory diseases in phase 2 clinical trials. Parasitic worms manipulate the immune system by secreting immunoregulatory molecules that offer promise as a novel therapeutic modality for inflammatory diseases. We identify a protein secreted by hookworms, anti-inflammatory protein-2 (AIP-2), that suppressed airway inflammation in a mouse model of asthma, reduced expression of costimulatory markers on human dendritic cells (DCs), and suppressed proliferation ex vivo of T cells from human subjects with house dust mite allergy. In mice, AIP-2 was primarily captured by mesenteric CD103⁺ DCs and suppression of airway inflammation was dependent on both DCs and Foxp3⁺ regulatory T cells (T_regs) that originated in the mesenteric lymph nodes (MLNs) and accumulated in distant mucosal sites. Transplantation of MLNs from AIP-2-treated mice into naïve hosts revealed a lymphoid tissue conditioning that promoted T_reg induction and long-term maintenance. Our findings indicate that recombinant AIP-2 could serve as a novel curative therapeutic for allergic asthma and potentially other inflammatory diseases.

Dietary Fiber and Bacterial SCFA Enhance Oral Tolerance and Protect against Food Allergy through Diverse Cellular Pathways

The incidence of food allergies in western countries has increased dramatically in recent decades. Tolerance to food antigens relies on mucosal CD103(+) dendritic cells (DCs), which promote differentiation of regulatory T (Treg) cells. We show that high-fiber feeding in mice improved oral tolerance and protected from food allergy. High-fiber feeding reshaped gut microbial ecology and increased the release of short-chain fatty acids (SCFAs), particularly acetate and butyrate. High-fiber feeding enhanced oral tolerance and protected against food allergy by enhancing retinal dehydrogenase activity in CD103(+) DC. This protection depended on vitamin A in the diet. This feeding regimen also boosted IgA production and enhanced T follicular helper and mucosal germinal center responses. Mice lacking GPR43 or GPR109A, receptors for SCFAs, showed exacerbated food allergy and fewer CD103(+) DCs. Dietary elements, including fiber and vitamin A, therefore regulate numerous protective pathways in the gastrointestinal tract, necessary for immune non-responsiveness to food antigens.

Epidemiology of anaphylaxis at a tertiary care center: A report of 730 cases

BACKGROUND

Recent data reveal that the rate of anaphylaxis is increasing and suggest that idiopathic anaphylaxis may account for most of these cases.

OBJECTIVE

To determine the pattern of anaphylaxis at a tertiary care referral center.

METHODS

A retrospective electronic medical record review spanning 12 years (2002-2013) identified patients with anaphylaxis.

RESULTS

Of the 4,777 records reviewed, 730 patients met our anaphylaxis definition. Median age was 34.0 years; 72.7% were adults, 58.6% were female, and 86.8% were white. Median time to evaluation by an allergist was 8.8 months. Foods were the most common cause (29.9%), followed by Hymenoptera venom (24.6%), idiopathic anaphylaxis (13.7%), and medications (13.3%). The most common foods were peanuts (23.9%), tree nuts (21.6%), shellfish (16.1%), and egg and milk (both 10.1%). The most common cause of anaphylaxis in adults was Hymenoptera venom. The most frequent symptoms were urticaria and/or angioedema, reported in 84.7% of cases. Atopy was present in 43.8%. In 15.4% of cases, anaphylaxis was not the chief reason for the office visit.

CONCLUSION

We found food allergy was the most common overall cause of anaphylaxis, with peanut the most frequent food trigger. Idiopathic anaphylaxis was not the most common cause but accounted for 13.7% of all cases. Approximately 1 in 6 cases of anaphylaxis may be missed if a comprehensive evaluation is not performed.

Anaphylaxis: epidemiology, aetiology and relevance for the clinic

INTRODUCTION

Anaphylaxis is responsible for considerable morbidity and may in some cases prove fatal. Areas covered: This review summarises the findings from recent studies on the epidemiology and aetiology of anaphylaxis and draws on the insights from this work and recent international guidelines to consider the implications for clinical care. Acute management of anaphylaxis is centred on early recognition, treatment with adrenaline (epinephrine) and other essential life-support measures. The importance of longer-term care of patients with a history of or at risk of anaphylaxis are also considered with a view to minimising the risk of further reactions. Tailored individual anaphylaxis management plans should be a routine component of this longer-term care with provision of adrenaline auto-injectors to those at risk of further episodes of anaphylaxis. More generally, there is a need to ensure that there are standard protocols in place to ensure that risks of triggering anaphylaxis are minimised and appropriate acute and long-term care are provided if reactions occur. Expert commentary: It is important to be aware that anaphylaxis may occur in patients of any age, sex or ethnicity. Early recognition and prompt treatment with adrenaline are potentially life-saving. Careful assessment of risk and appropriate long-term management are key to improving long-term outcomes in those at risk of repeat episodes of anaphylaxis.

Dermatologic surgery emergencies: Complications caused by systemic reactions, high-energy systems, and trauma

While the overall incidence of emergencies in dermatologic surgery is low, emergent situations can occasionally pose a risk to patients undergoing such procedures. The clinical importance of several types of emergences related to systemic reactions, high energy systems, and trauma are reviewed, and relevant epidemiology, clinical manifestations, diagnosis, work-up, management, and prevention are discussed. Early detection of surgical emergencies can mitigate any associated adverse outcomes, thereby allowing the outstanding record of safety of dermatologic surgery to continue.

Experimental food allergy to peanut enhances the immune response to house dust mite in the airways of mice

BACKGROUND

Food allergy has been associated with an increased risk for the development of allergic asthma. Asthma is a risk factor for the development of an anaphylactic response to food allergens. An immunological interplay between sensitization to different allergens in different compartments of the body might be involved.

OBJECTIVE

To evaluate the immunological interplay between intragastrical peanut (PE) sensitization and respiratory sensitization to house dust mite (HDM) allergens.

METHODS

BALB/c mice were intragastrically sensitized to peanut or sham-sensitized and challenged systemically to PE. Between sensitization and challenge, mice were intranasally exposed to HDM extract or PBS, as a control. The response to HDM (eosinophil recruitment, cytokine response, HDM-specific immunoglobulins and airway hyper-reactivity) and to PE (cytokine response, mast cells in gut, mMCP-1 in serum and body temperature) was assessed.

RESULTS

A preceding PE sensitization increased HDM-induced production of IL-4, IL-5, IL-13 and IFNγ in lung-draining lymph nodes and total IgE levels in HDM-sensitized mice. However, recruitment of inflammatory cells to the airways or airway hyper-reactivity was not aggravated in PE/HDM double-sensitized mice. Alternatively, HDM-induced airway inflammation did not significantly affect the immune response or the anaphylactic response to a systemic challenge with peanut.

CONCLUSION AND CLINICAL RELEVANCE

Our data show that a preceding peanut sensitization boosted IgE- and HDM-specific Th2 response in the airways in mice. It contributes to the understanding of the underlying immunological mechanism of polysensitization which often occurs in allergic individuals over time.

Co-morbidities and cognitive status in a cohort of teenagers with asthma

BACKGROUND

There is limited data regarding co-morbidities and cognitive status of asthma during childhood and adolescence. The aim of the current study was to explore the presence of co-morbidities and cognitive status in a large cohort of teenagers with asthma.

METHODS

The medical records of 314,897 consecutive 17-year-old males, undergoing comprehensive medical and cognitive evaluation prior to recruitment for military service, were reviewed. The prevalence of co-morbidities and a cognitive assessment in subjects with asthma were compared to those without asthma. Both a univariate and multivariate logistic regression analysis were performed.

RESULTS

Active asthma was documented in 21,728 (6.9%) subjects: 3.3% were diagnosed with mild intermittent asthma, and 3.6% with persistent asthma. A significant positive correlation between a higher cognitive score and prevalence of asthma was found (P < 0.001), with a 55% increased prevalence of asthma in the subjects with the highest cognitive score compared to those with the lowest score. The following co-morbidities were significantly more prevalent in asthmatics compared to non-asthmatics: chronic rhinitis (35% vs. 5%), atopic dermatitis (2% vs. 0.4%), urticaria (1% vs. 0.3%), anaphylaxis (0.4% vs. 0.1%), chronic sinusitis (0.4% vs. 0.1%), overweight with body mass index (BMI) above 25 kg/m(2) (20% vs. 17%) and underweight with BMI less than 17 kg/m(2) (3.2% vs. 2.8%), irritable bowel syndrome (IBS) (1% vs. 0.5%), and thyroid disorders(0.4% vs. 0.2%). Chronic rhinitis and sinusitis, atopic dermatitis, IBS, and thyroid disorders were all significantly more prevalent in persistent compared to intermittent asthma (P < 0.001).

CONCLUSIONS

In adolescence, a higher cognitive status was associated with a higher rate of asthma. Chronic rhinitis was the most prevalent co-morbidity and was found in one third of adolescent asthmatics. Other allergic diseases, chronic sinusitis, over and underweight, IBS, and thyroid disorders were also more prevalent in asthmatics. Pediatr Pulmonol. 2016; 51:901-907. © 2016 Wiley Periodicals, Inc.

Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy

The prevalence of allergic disorders including atopic dermatitis (AD) and food allergy (FA) has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB) extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3⁺CD4⁺ regulatory T cells (Tregs). The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3⁺CD4⁺ Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3⁺CD4⁺ Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs.

The diagnosis and management of children presenting with anaphylaxis to a metropolitan emergency department: A 2-year retrospective case series

AIM

To investigate the diagnosis and management of children with anaphylaxis presenting to an Emergency Department (ED). We compared the management with the Australasian Society of Clinical Immunology and Allergy (ASCIA) guidelines to gauge compliance.

METHODS

A retrospective case series was developed from children aged from birth to 16 years presenting to the ED at Sunshine Hospital (SH) in Melbourne, Australia over a 2-year period from 1 January 2012 to 31 December 2013. The demographic characteristics, causative agents, clinical features, treatment administered and discharge destination were recorded.

RESULTS

Fifty-five children diagnosed with anaphylaxis during the 2-year period were identified. Fifty-two children (95%) met the ASCIA diagnostic criteria, 49 (94%) children received adrenaline. The median age of presentation was five years, with males predominating (32 (62%)). The most common setting was home (35 (67%)), and food (39 (75%)) was the most common causative agent. Cutaneous symptoms (50 (96%)) were the most prevalent. Twenty-eight (54%) children received adrenaline prior to arrival in ED, whilst 22 (42%) received adrenaline in the ED. Thirty-three (63%) children were discharged home.

CONCLUSION

Childhood anaphylaxis commonly presents to the ED. More than half of children presenting with anaphylaxis were treated prior to attending the ED. The findings demonstrate that anaphylaxis diagnosis and management guidelines are being adhered to in the majority of cases. There were no adverse outcomes recorded.

β-Conglutin dual aptamers binding distinct aptatopes

An aptamer was previously selected against the anaphylactic allergen β-conglutin (β-CBA I), which was subsequently truncated to an 11-mer and the affinity improved by two orders of magnitude. The work reported here details the selection and characterisation of a second aptamer (β-CBA II) selected against a second aptatope on the β-conglutin target. The affinity of this second aptamer was similar to that of the 11-mer, and its affinity was confirmed by three different techniques at three independent laboratories. This β-CBA II aptamer in combination with the previously selected β-CBA I was then exploited to a dual-aptamer approach. The specific and simultaneous binding of the dual aptamer (β-CBA I and β-CBA II) to different sites of β-conglutin was confirmed using both microscale thermophoresis and surface plasmon resonance where β-CBA II serves as the primary capturing aptamer and β-CBA I or the truncated β-CBA I (11-mer) as the secondary signalling aptamer, which can be further exploited in enzyme-linked aptamer assays and aptasensors.

Anaphylaxis Preparedness among Preschool Staff before and after an Educational Intervention

Introduction. Children with severe food allergies may spend many hours in the preschool setting. Little is known about anaphylaxis recognition and management preparedness among preschool staff. The objective of this study was to assess anaphylaxis preparedness among preschool staff. Methods. Anonymous questionnaires were administered before and after a 40-minute educational seminar on anaphylaxis recognition and management. Results. In total, 181 individuals participated in the preintervention survey and 171 participated in the postintervention survey. The comfort level with recognizing anaphylaxis and administering an epinephrine autoinjector significantly increased after the intervention (P < .001 for both). Of the 5 steps needed to administer an epinephrine autoinjector, staff named a mean (SD) of 3 (1.3) steps in the correct order compared with 4.2 (1.1) steps after the educational intervention (P < .001). Conclusion. This study shows that a brief education intervention can significantly increase caregiver comfort regarding identifying anaphylaxis and administering an epinephrine autoinjector.

Early treatment of food-induced anaphylaxis with epinephrine is associated with a lower risk of hospitalization

BACKGROUND

Food-induced anaphylaxis (FIA) is potentially life threatening. Prompt administration of epinephrine is universally recommended by current treatment guidelines.

OBJECTIVE

To identify factors associated with early epinephrine treatment for FIA and to specifically examine the association between early epinephrine treatment and hospitalization.

METHODS

A chart review study conducted at Hasbro Children's Hospital/Rhode Island Hospital. By using the International Classification of Diseases, Ninth Revision codes, we identified all patients who presented to the emergency department with FIA between January 1, 2004, and December 31, 2009. Early epinephrine treatment was defined as receipt of epinephrine before arrival to the emergency department. The independent association between early epinephrine treatment and hospitalization was assessed using logistic regression.

RESULTS

Among the 384 emergency department visits for FIA identified during the study period, 234 patients received epinephrine (61%). Among this subset, most (164 [70%]) received early epinephrine treatment, whereas a smaller number of patients (70 [30%]) first received epinephrine in the emergency department (late treatment). Patients who received early epinephrine treatment were older (7.4 vs 4.3 years; P = .008), were more likely to have a known food allergy (66% vs 34%; P < .001), and were more likely to own an epinephrine autoinjector (80% vs 23%; P < .001). Patients treated early were less likely to be hospitalized (17% vs 43%; P < .001). After adjusting for age, sex, and race, the patients who received early epinephrine treatment remained at significantly decreased risk of hospitalization compared with those who received late epinephrine treatment (odds ratio 0.25 [95% CI, 0.12-0.49]).

CONCLUSIONS

In this population, early treatment of FIA with epinephrine was associated with significantly lower risk of hospitalization. Accordingly, this study supports the benefit of prompt administration of epinephrine for the treatment of FIA.

Predictors of the severity and serious outcomes of anaphylaxis in korean adults: a multicenter retrospective case study

Purpose

Differences in definitions of the condition, relevant triggers, and the geographical locations of study centers, cause estimates of the prevalence of anaphylaxis to vary. Recent epidemiological data indicate that the incidence of anaphylaxis is rising.

Methods

To investigate the causes and clinical features of anaphylaxis in Korean adults, factors associated with the severity of the condition, and serious outcomes, a retrospective medical record review was performed on adult patients diagnosed with anaphylaxis between 2007 and 2011 in 15 University Hospitals of South Korea.

Results

A total of 1,806 cases (52% male, age 16-86 years) were reported. Cutaneous symptoms (84.0%), combined with respiratory (53.9%) and/or cardiovascular (55.4%) symptoms, were the most frequent presentations. Using a recognized grading system, 1,776 cases could be classified as either mild, 340; moderate, 690; or severe, 746. Although eliciting factors varied significantly by age, gender, and regional and seasonal factors, drugs (46.5%; including nonsteroidal anti-inflammatory drugs, antibiotics, and radiocontrast media) were the most common cause of anaphylaxis, followed by foods (24.2%), insect stings (16.4%), exercise (5.9%), and unknown etiology (7.0%). All of age, multi-organ involvement, a history of allergic disease, and drug-induced anaphylaxis, were significant predictors of serious outcomes requiring hospital admission or prolongation of hospital stay. Epinephrine auto-injectors were prescribed for 7.4% of reported cases.

Conclusions

The principal causes of anaphylaxis in Korean adults were drugs, food, and insect stings. Drug-associated anaphylaxis, a history of allergic disease, multi-organ involvement, and older age, were identified as predictors of serious outcomes.

Pharmacists' response to anaphylaxis in the community (PRAC): a randomised, simulated patient study of pharmacist practice

OBJECTIVE

To evaluate how community pharmacists manage patients with anaphylaxis.

DESIGN

A randomised, cross-sectional, simulated patient study of community pharmacist practice.

SETTING

300 metropolitan pharmacies located in Perth Australia, randomised to three groups of 100 pharmacies. Each group corresponded to a different epinephrine autoinjector: original EpiPen, new-look EpiPen or Anapen.

PARTICIPANTS

300 pharmacies were visited with 271 simulated patient visits included in the final analysis (88=original EpiPen, 92=new-look EpiPen, 91=Anapen).

OUTCOME MEASURES

Primary anaphylaxis preparedness (readiness to treat acute anaphylaxis). Secondary anaphylaxis engagement (willingness to engage the patient in a discussion about their anaphylaxis).

METHODS

Simulated patients approached pharmacists, using a standardised scenario, for assistance with epinephrine autoinjector use and advice about the use of antihistamines in anaphylaxis. Scores for each outcome were obtained based on the number of predefined statements addressed by the pharmacist during the consultation (maximum score=5 for preparedness and 8 for engagement).

RESULTS

The mean anaphylaxis preparedness score was 2.39 points (SD 1.17). Scores for new-look EpiPen were significantly higher than for original EpiPen and Anapen (2.75 vs 2.38 points, p=0.027; 2.75 vs 2.03 points, p<0.001, respectively). Overall, 17.3% of pharmacists correctly demonstrated the epinephrine autoinjector. The mean anaphylaxis engagement score was 3.11 points (SD 1.73). Scores for new-look EpiPen were similar to original EpiPen and Anapen (3.11 vs 3.32 points; 3.11 vs 2.90 points, both p=0.42). Engagement was associated with preparedness. For each additional engagement point, preparedness increased by 7% (0.357 points; 95% CI 0.291 to 0.424; p<0.001).

CONCLUSIONS

Pharmacists demonstrated reasonable knowledge of anaphylaxis symptoms and emergency care, but had poor epinephrine autoinjector technique and rarely discussed anaphylaxis action plans. Pharmacists who had a more comprehensive discussion about anaphylaxis with patients, were more prepared for anaphylaxis emergencies. Future research should evaluate the nature and significance of errors in pharmacists' autoinjector technique.

Ultrasensitive aptamer based detection of β-conglutin food allergen

Lupine has been increasingly used in food applications due to its high nutritional value and excellent functional properties. However, there has been a response to the increasing number of severe cases of lupine allergies reported during the last decade, and as a result lupine was recently added to the list of substances requiring mandatory advisory labelling on foodstuffs sold in the European Union. In this paper we report the robust and ultrasensitive detection of the anaphylactic β-conglutin allergen using Apta-PCR achieving a detection limit of 85 pM (25 ng mL(-1)). No cross-reactivity with other conglutins or plant species potentially used in lupine containing foodstuffs was observed. This robust method provides an effective analytical tool for the detection and quantification of the toxic β-conglutin subunit present in lupine flour.

Concordance with recommended postdischarge care guidelines among children with food-induced anaphylaxis

OBJECTIVE

To describe patient characteristics, concordance with recommended postdischarge care, and risk of repeat events within a cohort of children discharged from an emergency department (ED) or hospital for food-induced anaphylaxis in the US.

STUDY DESIGN

Children (aged <18 years) with an ED visit/hospitalization for food-induced anaphylaxis were identified from the 2002-2008 Truven Health MarketScan databases using an expanded International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code algorithm. The initial identified ED visit/hospitalization was the index event. Claims data for the children with continuous medical and prescription coverage for ≥1 year before and after the index event were evaluated. Analyses included the rates of 1-year postdischarge epinephrine autoinjector (EAI) prescription fills, allergist/immunologist visits, and repeat events.

RESULTS

The study cohort comprised 1009 patients with an average age of 7 years, including 58% males, 27% with a history of asthma, and 90% discharged from an ED. Within 1 year postdischarge, 83% had an EAI prescription fill (69% within 1 week postdischarge), 43% had a specialist visit (51% within 4 weeks postdischarge), and 6.4% had evidence of another anaphylaxis-related ED visit/hospitalization.

CONCLUSION

Among children with food-induced anaphylaxis, within 1 year postdischarge from the ED or hospital, concordance was higher for EAI prescription fills than for allergist/immunologist visits. Subsequent ED visits/hospital stays for anaphylactic events were low. More research is needed to identify barriers between recommendations and physician/patient behaviors, as well as the impact of not following the recommendations on patient outcomes and healthcare costs.

[Anaphylaxis. Diagnostic and therapeutic management]

Anaphylaxis is a severe, potentially life-threatening, systemic allergic reaction, which generally happens unexpectedly in healthy individuals. Among children, the most common elicitors are food, insect stings, and drugs. Currently, the incidence of anaphylaxis is increasing. Risk factors are asthma, infections as well as previous, sudden respiratory and cardiovascular symptoms after exposure to a specific antigen. If cutaneous, respiratory, gastrointestinal, cardiovascular and neurologic symptoms involving ≥2 organ systems occur, adrenaline/epinephrine, preferably intramuscularly, should be administered. Although allergen skin testing and serological estimation of specific IgE antibodies do not predict who will develop anaphylaxis, they help to identify sensitized individuals at risk. Patients with a history of anaphylaxis need training on how to use the emergency medication and how to recognize and prevent the anaphylactic symptoms.

The utility of serum tryptase in the diagnosis of food-induced anaphylaxis

Purpose

This study investigates the utility of serum tryptase for the confirmation of shrimp-induced anaphylaxis.

Methods

Patients with a history of shrimp allergy and positive skin prick tests (SPT) to commercial shrimp extract were recruited for shrimp challenges. Serum total tryptase was obtained at baseline and 60 min (peak) after the onset of symptoms.

Results

Thirty-nine patients were challenged. There were 12 patients with anaphylaxis, 20 with mild reactions and 7 without symptoms (control group). Characteristic features and baseline tryptase were not different among the 3 groups. The peak tryptase levels were higher than the baseline in anaphylaxis and mild reaction groups (P<0.05). The delta-tryptase (peak minus baseline) and the tryptase ratio (peak divided by baseline) in the anaphylaxis group were higher than the mild reaction and control groups (P<0.01). The optimum cut-off for peak tryptase to confirm anaphylaxis was 2.99 µg/L with 50% sensitivity, 85% specificity, 3.33 positive likelihood ratio (LR) and 0.59 negative LR. The manufacturer's cut-off for peak tryptase was >11.4 µg/L with 17% sensitivity, 100% specificity, infinity positive LR and 0.83 negative LR. The best cut-off for delta-tryptase was ≥0.8 µg/L with 83% sensitivity, 93% specificity, 11.86 positive LR and 0.18 negative LR. The best cut-off for tryptase ratio was ≥1.5 with 92% sensitivity, 96% specificity, 23 positive LR and 0.08 negative LR.

Conclusions

The peak tryptase level should be compared with the baseline value to confirm anaphylaxis. The tryptase ratio provide the best sensitivity, specificity, positive and negative LR than a single peak serum tryptase for the confirmation of shrimp-induced anaphylaxis.

Anaphylaxis: opportunities of stratified medicine for diagnosis and risk assessment

The risk to develop anaphylaxis depends on the sensitization pattern, the proportion of the involved immunoglobulin classes, the avidity and affinity of immunoglobulins to bind an allergen, characteristics of the allergen, the route of allergen application, and, last but not least, the presence of cofactors of anaphylaxis. To be able to calculate the risk to develop anaphylaxis and to anticipate the severity of the reactions under certain conditions, it is necessary to understand how all these factors interact with each other. Important progress for risk assessment in anaphylaxis is based on component-resolved stratified diagnostics, which allow to (i) determine a patient's sensitization pattern on a molecular basis, (ii) correlate clinical responses to defined sensitization patterns, and (iii) better identify cross-reactive allergens. Together with the increasing knowledge regarding the role and mode of action of cofactors of anaphylaxis, these data pave the way to unscramble the complex interactions determining the clinical relevance of sensitizations, the risk of anaphylaxis, and the severity of reactions. As a consequence, this understanding allows to better determine the individual risk in response to an identified allergen and results in more specific advices and education for our patients to prevent further life-threatening anaphylactic reactions.

Knowledge and attitudes of primary care physicians regarding food allergy and anaphylaxis in Turkey

BACKGROUND

Food allergy, which becomes an important public health problem, can lead to important morbidity and mortality. Patients with food allergies are more likely to first present to their primary care physicians. We aimed to determine the knowledge of primary care physicians with regard to management of food allergies and anaphylaxis.

METHODS

Primary care physicians were surveyed via a questionnaire aimed to document their knowledge and attitudes about food allergy and anaphylaxis management.

RESULTS

A total of 297 participants completed questionnaires, 55.6% of which were female. Participating physicians had a mean of 17.0 ± 6.1 years of experience. Participants answered 47.2% of knowledge-based items correctly. Overall, participants fared poorly with regard to their knowledge on the treatment of food allergies and anaphylaxis. For example while 60.7% knew that a child can die from the milk allergy reaction, only 37.5% were aware that a child with IgE mediated milk allergies cannot eat yoghourts/cheese with milk. Besides, 53.1% of them chose epinephrine as their first treatment of choice in case of anaphylaxis, yet only 16.6% gave the correct answer about its dosage. Nearly a third of participants (36.7%) felt they were knowledgeable enough regarding the management of patients with food allergies, while 98.2% extended their request for future periodic educational meetings on allergic disorders.

CONCLUSION

Knowledge of food allergy and anaphylaxis among primary care physicians was unsatisfactory. Provision or periodic educational programmes should be aimed at improving the standard of practice as acknowledged by the participants.

About the role and underlying mechanisms of cofactors in anaphylaxis

Anaphylaxis is the systemic and most severe presentation of type I allergy. A number of conditions were identified that modulate the onset of anaphylaxis such as co- or augmentation factors, which significantly lower the allergen dose necessary for triggering anaphylaxis. Next to physical exercise or alcohol consumption, co-administration of nonsteroidal anti-inflammatory drugs (NSAID) or concomitant infectious diseases are well-documented cofactors of anaphylaxis. Registries for anaphylaxis document a role for cofactors in about 30% of anaphylactic reactions. Some disease entities such as 'wheat-dependent exercise-induced anaphylaxis' (WDEIA) are explicitly characterized by elicitation of anaphylaxis only in the presence of at least one such cofactor. Using WDEIA as a model disease, studies demonstrated that exercise increases skin prick test reactivity to and bioavailability of the allergen. Additional data indicate that alcohol consumption and NSAID administration display similar effects. Modulation of the cellular activation threshold is another mechanism underlying cofactor-induced anaphylaxis, most likely also functional when infectious diseases orchestrate elicitation of anaphylaxis. Cofactors are increasingly accepted to play a fundamental role in eliciting anaphylaxis. Consequently, to improve patient management modalities, a better understanding of the underlying mechanisms is warranted. This review aims to update clinicians and clinical scientists on recent developments.

Infant anaphylaxis: the importance of early recognition

Anaphylaxis is an acute severe reaction involving multiple systems that results from a rapid release of inflammatory mediators. Patients with asthma and prior allergic reactions are at risk for anaphylaxis. Infants can present a special challenge, as the hallmark symptoms and signs of anaphylaxis may be mistaken as normal findings. These include drooling, vomiting or diarrhea, scratching, and drowsiness. The clinical manifestations of anaphylaxis are broad, as a result of it being a systemic response to an external agent. Among infants and children, there are often respiratory and cutaneous findings. There also can be subtle signs and symptoms, which can often be missed or the findings misinterpreted as normal for developmental age. The incidence of anaphylaxis has increased globally among children presenting with allergic reactions. Early recognition of the signs and symptoms is crucial to effective diagnosis and treatment. This is particularly true among infants 13 months of age or younger who are nonverbal and may have subtle signs and symptoms of a life-threatening reaction to allergens. The purpose of this article is to highlight the differential clinical presentations of young children with anaphylaxis.

Treatment of a simulated child with anaphylaxis: an in situ two-arm study

AIM

This study aims to determine whether junior medical staff correctly identify and treat paediatric anaphylaxis and whether the presence or absence of hypotension influenced the treatment, using a standardised simulated patient encounter.

METHODS

Junior medical staff from the emergency department of a large paediatric tertiary hospital were invited to participate in a two-armed cohort study to assess recognition and management of anaphylaxis in a standardised scenario using a simulated patient with and without hypotension. The primary outcome measure was administration of adrenaline. The secondary outcome measures included time to adrenaline administration, ability to seek and identify relevant features of history and clinical examination and use of other medications.

RESULTS

Fifty-six junior medical staff participated (90% participation rate). Only 50% of participants administered adrenaline in scenarios of definite anaphylaxis. Adrenaline was more likely to be administered if the scenario included hypotension, where the junior medical officer had previous formal resuscitation training (Advanced Paediatric Life Support) and by medical officers with more years of training.

CONCLUSION

Anaphylaxis is a life-threatening presentation and requires prompt recognition and appropriate adrenaline administration. Junior medical staff may require more emphasis on recognition and prompt adrenaline administration in both undergraduate and in hospital training and education. Simulated scenarios may provide a platform to deliver this training to ultimately improve patient care.

Common features of anaphylaxis in children

OBJECTIVE

We aimed to establish the characteristics of anaphylaxis in childhood.

METHODS

Forty-four patients who had experienced anaphylaxis in a period of 10 years (from 1999 to 2009), were included in the study. Parameters analysed were age, gender, concomitant allergic disease, trigger, setting, clinical symptoms, treatment, prognosis and prophylaxis.

RESULTS

The total numbers of anaphylaxis cases were 44 in a ten-year period. The ages of patients ranged from 3 to 14 years (11.50 ± 3.87 years) and the majority were male. 33 of the patients (75%) had a concomitant allergic disease. The trigger was determined in 93.2% of the cases, being most frequent: food (27.3%), and SIT (25%), followed by bee sting, medications and others. Respiratory (95.5%), dermatological (90.9%), cardiovascular (20.5%), neuropsychiatric (25%), and gastrointestinal (11.4%) symptoms were seen most frequently. For anaphylaxis triggered by food, the duration of anaphylactic episode was significantly longer (p<0.05). No biphasic reaction was observed during these attacks. Of our patients, only one developed respiratory failure and cardiac arrest due to SIT, and intensive care support was required.

DISCUSSION

As a trigger for anaphylaxis, the frequency of SIT is so high that it cannot be described by the study group including patients who were followed up in an outpatient allergy clinic.

The aryl hydrocarbon receptor and food allergy

The immune system is important for protection against pathogens and malignant cells. However, malfunction of the immune system can also result in detrimental auto-immune diseases, inflammatory diseases, cancers and allergies. The aryl hydrocarbon receptor (AhR), present in numerous tissues and cell subsets, including cells of the immune system, plays an important role in the functioning of the immune system. Activation of the AhR is for example associated with various effects on dendritic cells (DCs), regulatory T cells and the Th1/Th2 cell balance. These cells play a major role in the development of food allergy. Food allergy is an increasing health problem in both humans and animals. Despite the knowledge in risk factors and cellular mechanisms for food allergy, no approved treatments are available yet. Recently, it has been shown that activation of the AhR by dioxin-like compounds suppresses allergic sensitization by suppressing the absolute number of precursor and effector T cells, by preserving CD4(+)CD25(+)Foxp3(+) Treg cells and by affecting DCs and their interaction with effector T cells. Future research should elucidate whether and how AhR activation can be used to interfere in food allergic responses in humans and in animals. This may lead to new prevention strategies and therapeutic possibilities for food allergy.

Therapeutic Management of Accidental Epinephrine Injection

Objective:

To review the literature regarding therapeutic options for accidental epinephrine exposure via EpiPen (Mylan Specialty Inc.) autoinjector devices and to suggest a treatment algorithm based on the most common approaches found therein.

Data Sources:

A literature search of MEDLINE (1950-March 2012) was conducted, using the search term accidental epinephrine injection in combination with the terms adrenaline, EpiPen, anaphylaxis, autoinjector, and treatment. Case reports, case series, and systematic reviews were evaluated for efficacy and safety data. In addition, the references of the reviewed articles were examined to identify additional reports or data.

Study Selection and Data Extraction:

All English-language articles describing accidental exposure to epinephrine were identified. Our search included both pediatric and adult patient populations. Articles were excluded if the exposure to epinephrine was purposeful and the EpiPen described in the report was being used as intended or the outcome was not clear. Individual case reports were described in detail whereas case series and systematic reviews were included but were not described in detail. To our knowledge, there have been no clinical trials that describe or compare therapeutic options for accidental exposure to epinephrine.

Data Synthesis:

Accidental exposure to epinephrine is an underreported phenomenon that could warrant medical attention. The importance of this issue has recently been emphasized with the legislative requirement of many schools to store epinephrine (EpiPen) autoinjector devices. The available therapeutic options can be divided into pharmacologic and nonpharmacologic categories. The most common pharmacologic options described in the literature include phentolamine, subcutaneous terbutaline, topical nitrates, and calcium channel blockers. Nonpharmacologic options include observation and/or warm water soaks. Treatment recommendations in our proposed algorithm were based solely on the available data that we describe in our review.

Conclusions:

The literature did not provide clear guidance on the most appropriate management of accidental epinephrine injection. However, if pharmacologic therapy is necessary, phentolamine appears to be considered the most effective. Guidelines may be helpful in improving the management of accidental epinephrine injection, as well as in preventing unnecessary therapy.