International consensus on (ICON) anaphylaxis

Asthma and anaphylaxis

PURPOSE OF REVIEW

Both asthma and anaphylaxis are recognized noncommunicable hypersensitivity conditions, which should be correctly diagnosed and treated/controlled in order to decrease avoidable deaths. Nevertheless, their association is not completely clear. We here propose to review the current and new evidence-based data of asthma and anaphylaxis in the view of the new knowledge in the field that can support the quality practice and empower allergists and health professionals in treating symptoms and preventing death.

RECENT FINDINGS

Hypersensitivity life-threatening conditions, such as anaphylaxis and asthma can coexist, mimic or worse each other. Asthma itself is not a strong predictor of more severe anaphylaxis. However, poor asthma control associated with more severe anaphylaxis reactions in all ages. In children, asthma is associated with the severity and recurrences of anaphylactic reactions.

SUMMARY

Although recent data point for the association between asthma and anaphylaxis, we still do not have harmonized evidence to confirm if we are dealing with two independent comorbidities one worsening each other. However, as far as this review is covering two relevant public health problems in the field of allergy, it is mandatory put in place decisions supporting recommendations to better manage the affected patients and reduce the risk.General strategies should include regular notification of this association, optimization of the classification and coding for anaphylaxis and asthma (new ICD 11 allergy codes) in order to harmonize epidemiological stratified data, early diagnosis of asthma in childhood, regular investigation of asthma in cases of anaphylaxis and optimization of the asthma control and lung function for all patients with indication to provocation tests, desensitization or allergen immunotherapy regardless to the trigger. Implementation of these strategies will involve national and international support for ongoing efforts in relationship with networks of centres of excellence to provide personalized management for the most at-risk patients and prevent death.

Biologics and anaphylaxis

PURPOSE OF REVIEW

The use of biologicals as therapeutic agents in oncology and other inflammatory diseases has dramatically increased during the last years. Due to their biological nature and inherent immunological activity, they are able to induce important adverse events, such as cytokine release reactions (rapid release of proinflammatory cytokines), serum sickness disease, and immediate or delayed hypersensitivity reactions, including anaphylaxis. The aim of the current article is to review the state of the art of anaphylaxis because of biological agents.

RECENT FINDINGS

Different phenotypes, and potential underlying endotypes, have been described in anaphylactic reactions to biologicals. There seems to be a spectrum from type 1 reactions (IgE or non-IgE-mediated) to cytokine release reactions, with some reactions falling in between both. Management should be directed according to such phenotypes.

SUMMARY

There is ongoing research to further define immediate adverse reactions to biologicals and to find relevant biomarkers to aid in their diagnosis. Such information will serve in defining their immediate and long term management.

Self-injectable epinephrine: doctors' attitude and patients' adherence in real-life

PURPOSE OF REVIEW

Epinephrine is the only life-saving treatment of anaphylaxis. Prescription and administration rates of self-injectable epinephrine are generally low. It is unclear whether this is because of availability, low prescription rates, fear of using epinephrine, or a combination of these issues.

RECENT FINDINGS

This review focuses on what self-injectable epinephrine devices (SIED), such as auto-injectors and prefilled syringes, are preferred by patients and healthcare professionals (HCP). Our findings suggest that a device's ease to use, proper and frequent training on its operability, and availability have an impact on preferences and adherence to treatment with SIEDs. After prescribing a patient with a SIED, clinicians should emphasize its use in anaphylaxis, educate patients/caregivers to identify anaphylaxis and on how to use the SIED, and encourage constant practicing with training devices.

SUMMARY

Epinephrine is the sole recommended anaphylaxis treatment and SIEDs are of critical usefulness in the community setting. Further studying of these devices is needed to optimize education for HCPs and patients and their accessibility to SIEDs.

Establishing Standardized Documentation for Anaphylaxis Treatment in a Tertiary Care Pediatric Allergy Clinic

Supplemental Digital Content is available in the text.

Introduction:

Anaphylaxis is a potentially life-threatening allergic reaction. Common allergy clinic procedures, including oral food challenges and subcutaneous immunotherapy, carry a risk of anaphylaxis, the treatment for which is epinephrine. Our goal was to develop a standardized process for the management and documentation of allergic reactions that occur in a tertiary care pediatric allergy clinic.

Methods:

This was a single institution quality improvement pilot study. A multidisciplinary team from the allergy department designed, implemented, and studied the use of a standardized form for the documentation and treatment of allergic reactions within the clinic.

Results:

A standardized form was developed based on evidence-based guidelines for the management of allergic reactions and included space for documentation. Both clinic providers and staff approved the form. One year after the introduction, we reached 100% adherence for the use of the form in visits during which a patient experienced a severe allergic reaction requiring epinephrine. Two patients required transfer to the emergency room; the quality improvement form was utilized in these cases to document treatment and assist with the hand-off to emergency room personnel before transfer.

Conclusions:

We successfully implemented a standardized form for the treatment and documentation of anaphylaxis within our allergy clinic. The next steps focus on further integrating this form into the electronic medical record, determining compliance with evidence-based management of anaphylaxis, and formally assessing the use of the form as a handoff tool in the event of patient transfer.

Drug-Induced Anaphylaxis: An Update on Epidemiology and Risk Factors

Drug hypersensitivity is one of the most frequent causes of anaphylaxis, particularly in adults and in hospitalized patients. Drug-induced anaphylaxis (DIA) is also associated with more severe outcomes than other anaphylaxis triggers, and drugs are responsible for the majority of deaths due to anaphylaxis. We here review the current knowledge on the incidence, prevalence, drugs involved, mortality, and mortality risk factors for DIA. The incidence of both anaphylaxis and DIA seems to be increasing worldwide. Antibiotics and analgesics are the most frequently reported triggers of DIA. However, the importance of other drug groups should be taken into account, especially in particular settings (e.g., peri-operative and oncology). The identification of risk factors, geographical variables, and drugs associated with higher risk for DIA may improve the outcomes of this entity.

Epinephrine auto-injector needle length: The impact of winter clothing

BACKGROUND

Epinephrine auto-injectors are expected to deliver the drug intramuscularly.

OBJECTIVE

To study whether injection through clothing influences the frequency of subcutaneous and intraosseous/periosteal deposition of epinephrine.

METHODS

Skin to muscle and skin to bone distances were measured for 303 children and adolescents and 99 adults. Distance was determined by ultrasound, with high or low pressure on the ultrasound probe. The risk/percentage of subcutaneous and intraosseous/periosteal injections was calculated using the lower and upper limits for the authority-approved length of EAI needles as provided by two high pressure EAI manufacturers and one low pressure EAI manufacturer. The addition winter clothing on the delivery of epinephrine was illustrated by comparing drug delivery fissue depth with no clothes. Furthermore, the riof non-intramuscular delivery for the shortest and longest approved needle length was calculated.

RESULTS

When using EpipenJr® in children < 15 kg the risk of intraosseous/periostal injection was reduced from 1% and 59% for the shortest and longest approved needle length to 0 and 15% with winter clothes. The Auvi-Q® 0.1 mg had no risk of intraosseous/periosteal injection. However, the subcutaneous deposition risk increased from 94% and 28% to 100% and 99% with winter clothes. The risk of subcutaneous injection using EpipenJr® in the youngest children increased from 13% and 0% to 81% and 1% with winter clothes, and with Epipen® in adults from 45% and 17% to 60% and 38%. Emerade®, had a risk of subcutaneous injection in adults increasing from 14% and 10% to 28% and 21% adding winter clothes.

CONCLUSION

The risk of intraosseous/periosteal injections decreases and the risk of subcutaneous injection increases when injecting through winter clothes for all EAIs.

Anaphylaxis-a 2020 practice parameter update, systematic review, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis

Anaphylaxis is an acute, potential life-threatening systemic allergic reaction that may have a wide range of clinical manifestations. Severe anaphylaxis and/or the need for repeated doses of epinephrine to treat anaphylaxis are risk factors for biphasic anaphylaxis. Antihistamines and/or glucocorticoids are not reliable interventions to prevent biphasic anaphylaxis, although evidence supports a role for antihistamine and/or glucocorticoid premedication in specific chemotherapy protocols and rush aeroallergen immunotherapy. Evidence is lacking to support the role of antihistamines and/or glucocorticoid routine premedication in patients receiving low- or iso-osmolar contrast material to prevent recurrent radiocontrast media anaphylaxis. Epinephrine is the first-line pharmacotherapy for uniphasic and/or biphasic anaphylaxis. After diagnosis and treatment of anaphylaxis, all patients should be kept under observation until symptoms have fully resolved. All patients with anaphylaxis should receive education on anaphylaxis and risk of recurrence, trigger avoidance, self-injectable epinephrine education, referral to an allergist, and be educated about thresholds for further care.

A 5-year retrospective review of children with peanut allergy in the largest paediatric hospital in Singapore

Background

The prevalence of peanut allergy (PA) among children has increased significantly over the past decade. Even though the prevalence of PA in Singapore is considered low, peanut is the top trigger for food-induced anaphylaxis in Singaporean children.

Objective

To describe the demographic characteristics and clinical features of children with PA.

Methods

This is a 5-year retrospective review of children diagnosed with PA based on clinical history coupled with a positive skin prick test to peanut or positive oral food challenge results.

Results

There were 269 patients (53.9% males) with a clinical diagnosis of PA. The median age at first allergic presentation for the PA group was 24 months old, with interquartile range of 13-39 months. The most common form of peanut introduced was roasted peanut. The rate of peanut anaphylaxis was 7.1%. Concomitant tree nut sensitization was found in 32.3% of this cohort, predominantly to cashew nut. Majority of them have a personal history of atopy - 75.8% with eczema, 63.6% with allergic rhinitis, and 19.7% with asthma.

Conclusion

This is the first large review of peanut-allergic children in Singapore. Prospective population-based studies are needed to establish the true prevalence and risk factors associated with the development of this potentially life-threatening condition.

Increased Urinary 3-Mercaptolactate Excretion and Enhanced Passive Systemic Anaphylaxis in Mice Lacking Mercaptopyruvate Sulfurtransferase, a Model of Mercaptolactate-Cysteine Disulfiduria

Mercaptopyruvate sulfurtransferase (Mpst) and its homolog thiosulfate sulfurtransferase (Tst = rhodanese) detoxify cyanide to thiocyanate. Mpst is attracting attention as one of the four endogenous hydrogen sulfide (H₂S)/reactive sulfur species (RSS)-producing enzymes, along with cystathionine β-synthase (Cbs), cystathionine γ-lyase (Cth), and cysteinyl-tRNA synthetase 2 (Cars2). MPST deficiency was found in 1960s among rare hereditary mercaptolactate-cysteine disulfiduria patients. Mpst-knockout (KO) mice with enhanced liver Tst expression were recently generated as its model; however, the physiological roles/significances of Mpst remain largely unknown. Here we generated three independent germ lines of Mpst-KO mice by CRISPR/Cas9 technology, all of which maintained normal hepatic Tst expression/activity. Mpst/Cth-double knockout (DKO) mice were generated via crossbreeding with our previously generated Cth-KO mice. Mpst-KO mice were born at the expected frequency and developed normally like Cth-KO mice, but displayed increased urinary 3-mercaptolactate excretion and enhanced passive systemic anaphylactic responses when compared to wild-type or Cth-KO mice. Mpst/Cth-DKO mice were also born at the expected frequency and developed normally, but excreted slightly more 3-mercaptolactate in urine compared to Mpst-KO or Cth-KO mice. Our Mpst-KO, Cth-KO, and Mpst/Cth-DKO mice, unlike semi-lethal Cbs-KO mice and lethal Cars2-KO mice, are useful tools for analyzing the unknown physiological roles of endogenous H₂S/RSS production.

Anaphylaxis diagnosis and management in the Emergency Department of a tertiary hospital in the Philippines

Background

In the Emergency Department (ED), diagnosis and management of anaphylaxis are challenging with at least 50% of anaphylaxis episodes misdiagnosed when the diagnostic criteria of current guidelines are not used.

Objective

Objective of our study was to assess anaphylaxis diagnosis and management in patients presenting to the ED.

Methods

Retrospective chart review conducted on patients presenting to The Medical City Hospital ED, the Philippines from 2013–2015 was done. Cases were identified based on International Statistical Classification of Diseases, 10th revision coding for either anaphylaxis or other allergic related diagnosis. Cases fitting the definition of anaphylaxis as identified by the National Institute of Allergy and Infectious Disease and the Food Allergy and Anaphylaxis Network (NIAID/FAAN) were included. Data collected included demographics, signs and symptoms, triggers and management.

Results

A total of 105 cases were evaluated. Incidence of anaphylaxis for the 3-year study period was 0.03%. Of the 105 cases, 35 (33%) were diagnosed as “urticaria” or “hypersensitivity reaction” despite fulfilling the NIAID/FAAN anaphylaxis criteria. There was a significant difference in epinephrine administration between those given the diagnosis of anaphylaxis versus misdiagnosed cases (61 [87%] vs. 12 [34%], χ² = 30.77, p < 0.01); and a significant difference in time interval from arrival at the ED to epinephrine administration, with those diagnosed as anaphylaxis (48%) receiving epinephrine within 10 minutes, versus ≥ 60 minutes for most of the misdiagnosed group (χ² = 52.97, p < 0.01).

Conclusion

Despite current guidelines, anaphylaxis is still misdiagnosed in the ED. Having an ED diagnosis of anaphylaxis significantly increases the likelihood of epinephrine administration, and at a shorter time interval.

The Canadian anaphylaxis action plan for kids: development and validation

OBJECTIVES

We designed a written Canadian Anaphylaxis Action Plan for Kids (Kids' CAP) which incorporates validated pictograms with written instructions. Using a patient-centered approach, we aimed to validate the Kids' CAP and assess its impact on anaphylaxis recognition and treatment, and to determine its' perceived usefulness.

PATIENT INVOLVEMENT

Children and their parents were involved in appraising the design and written contents of the Kids' CAP.

METHODS

The design process consisted of a development phase and clinical validation phase. First, we assessed the readability and understandability of the Kids' CAP using validated instruments. Then, patients (12-17 years of age) and parents of patients (<12 years of age) were given the Kids' CAP during the first consultation with allergy specialists or an Emergency Department visit for anaphylaxis. Subsequently, we conducted a phone interview 2-3 weeks later to assess their comprehension of anaphylaxis management. We also used the Consumer Information Rating Form to measure the participants' perception of the design quality and usefulness of the Kids' CAP.

RESULTS

Of the 230 participants enrolled, 205 (89%) completed the follow-up interview. The written contents of the Kid's CAP were modified to match grade 7 readability level. The total mean score of the Consumer Information Rating Form for comprehensibility was 23.1 (SD 2.4), and 25.1 (SD 2.3) for design quality. The mean comprehension score was 11.3 (SD 1.8) (reference range 0-12), with no significant difference between participants with and without previous experience with anaphylaxis, or high vs. low literacy level.

CONCLUSION

Engaging children and parents in the design and contents of written anaphylaxis action plan is an innovative approach to produce a useful document for the end-users.

PRACTICE IMPLICATIONS

The Kids' CAP is a valid tool that can be used in emergency departments and allergy clinics to improve patient's comprehension of anaphylaxis manifestations and treatment.

Idiopathic anaphylaxis: What you do not know may hurt you

Idiopathic anaphylaxis (IA), like immunologic and nonimmunologic anaphylaxis, is a life-threatening, sometimes fatal allergic disease. Although the priority is immediate recognition and initiation of treatment, long-term care planning is important to help reduce anxiety and promote healthy growth and development. Learning to recognize, manage, and stabilize the child is an essential part of improving the family dynamics. Despite advancements in the management of anaphylaxis, research has shown a need for continued patient education and training to improve timely recognition and treatment. This article focuses on elucidating the clinical presentation, theories of pathogenesis, and diagnosis, treatment, and management of IA.

Low Incidence of Biphasic Allergic Reactions in Patients Admitted to Intensive Care after Anaphylaxis

BACKGROUND

Biphasic allergic reactions-recurrence of allergy symptoms after a symptom-free period-are reported to occur in 1 to 23% of allergic reactions. Patients admitted to an intensive care unit after anaphylaxis potentially have more severe reactions and a higher risk of biphasic allergic reactions. The purpose of this study was to examine incidence, triggers, symptoms, and treatment of biphasic allergic reactions, in patients admitted to an intensive care unit.

METHODS

Records of patients admitted to intensive care units with anaphylaxis from 2011 to 2014 were reviewed. Only patients with a reaction fulfilling internationally accepted criteria for anaphylaxis were included. Potential biphasic allergic reactions, defined as renewed allergy symptoms 1 to 72 h after initial symptoms had resolved, without further exposure to the trigger, were identified.

RESULTS

A total of 83 cases of anaphylaxis were identified, and the most frequent triggers were medications (58 of 83 [70%]). Skin symptoms occurred in 69 (83%) cases, and circulatory and respiratory symptoms in 48 (58%) and 45 (54%) cases, respectively. In total, 82 (99%), 80 (96%), and 66 (80%) were treated with antihistamines, corticosteroids, and epinephrine, respectively. Only 10 patients presented with one or more relevant symptoms after the initial allergic reaction. Of these, three were possible, and one was a probable biphasic allergic reaction, giving a total incidence of 4 of 83 (4.8% [95% CI, 1.6 to 12.5]) or 1 of 83 (1.2% [95% CI, 0.1 to 7.46]), respectively. All cases were mild, presenting with skin symptoms only, occurring on average 14 h after initial reactions.

CONCLUSIONS

The authors observed a low incidence of biphasic reactions in patients admitted to an intensive care unit after anaphylaxis, at a rate equivalent to that reported in other patient groups.

Improving adrenaline autoinjector adherence: A psychologically informed training for healthcare professionals

BACKGROUND

Clinicians draw on instructional approaches when training patients with anaphylaxis to use adrenaline autoinjectors, but patient use is poor. Psychological barriers to these behaviours exist but are not considered routinely when training patients to use autoinjectors. Health Psychology principles suggest exploring these factors with patients could improve their autoinjector use.

OBJECTIVE

To evaluate the impact of a 90-minute workshop training clinicians in strategies and techniques for exploring and responding to psychological barriers to autoinjector use with patients. Attendees' knowledge, confidence and likelihood of using the strategies were expected to improve.

METHODS

Impact was evaluated using a longitudinal mixed-method design. Twenty-nine clinicians (general and specialist nurses, general practitioners, and pharmacists) supporting patients with anaphylaxis in UK hospitals and general practice attended. Self-rated knowledge, confidence, and likelihood of using the strategies taught were evaluated online 1 week before, 1 to 3, and 6 to 8 weeks after the workshop. Clinicians were invited for telephone interview after attending to explore qualitatively the workshop impact.

RESULTS

χ2 analyses were significant in most cases (P < .05), with sustained (6-8 weeks) improvements in knowledge, confidence, and likelihood of using the strategies taught. Thematic analysis of interview data showed the workshop enhanced attendees' knowledge of the care pathway, understanding of patient's experience of anaphylaxis as psychological not purely physical, and altered their communication with this and other patient groups. However, interviewees perceived lack of time and organisational factors as barriers to using the strategies and techniques taught in clinical contexts.

CONCLUSION

Training clinicians in psychologically informed strategies produce sustained improvements in their confidence and knowledge around patient autoinjector education, and their likelihood of using strategies in clinical practice.

CLINICAL RELEVANCE

Exploring psychological barriers should be part of training patients with anaphylaxis in autoinjector use.

Serum Baseline Tryptase Level as a Marker for the Severity of Anaphylaxis

BACKGROUND

Anaphylaxis is a severe and potentially fatal allergic disease or hypersensitivity reaction with variable clinical presentation. Biomarkers in anaphylaxis could be useful to improve diagnosis, to allow endotyping of patients, and to predict risk.

OBJECTIVE

To investigate the role of serum basal tryptase (sBT) levels in the management of patients with anaphylaxis.

METHODS

Patients with at least 1 episode of anaphylaxis were selected among those who attended the Allergy Clinics of the Clinical Hospital of the Ribeirão Preto Medical School, University of São Paulo, Brazil, upon evaluation by allergy/immunology specialists of our medical staff. Demographic and clinical data were obtained using a structured questionnaire. sBT levels were determined using the ImmunoCAP Tryptase immunoassay.

RESULTS

57 patients (56.1% female) with a median age of 35 years (range 7-87 years) participated in the study. sBT levels ranged from 2.57 to 21.19 ng/mL (mean 5.17 ng/mL), with no significant differences in patients with anaphylaxis due to different triggers. Mean levels were 4.93; 5.2; 5.41, and 5.24 ng/mL for patients who had anaphylaxis due to Hymenoptera venom (n = 17), foods (n = 13), drugs (n = 13), and idiopathic disease (n = 14), respectively. Significantly higher sBT levels were observed in patients with severe anaphylaxis (grade IV) than in patients with mild-moderate disease (grades II/III) (mean levels 6.61 vs. 4.71 ng/mL, respectively).

CONCLUSION

High sBT levels may help to identify patients at increased risk of more severe anaphylaxis, prompting physicians to initiate immediate therapy to avoid further acute episodes.

Suspected anaphylactic shock associated with administration of tranexamic acid in a dog

A 10-year-old male castrated Maltese was referred with clinical signs of hematuria, stranguria, and pollakiuria. The dog was diagnosed with sterile hemorrhagic cystitis with urethroliths and cystoliths. To remove the uroliths, the dog underwent retrograde urohydropropulsion followed by a cystotomy. The following day, persistent bleeding in the urinary bladder was identified with large hematoma, hematuria and anemia. In order to reduce bleeding, the dog received 10 mg/kg of tranexamic acid (TXA) intravenously. Immediately after TXA administration, the dog developed anaphylactic shock manifested by hypotension, hypothermia, tachycardia and a dull mentation. Thus, an emergency treatment including bolus injection of crystalloid, administration of dexamethasone and diphenhydramine, and oxygen supplementation was given, after which the dog quickly recovered within a few minutes.

A biotinylated peptide, BP21, alleviates hypotension in anaphylactic mice

Platelet-activating factor (PAF) is known as an important mediator of anaphylaxis and, therefore, may possibly serve as a direct target for anti-anaphylactic drugs. We recently reported that a synthetic N-terminally biotinylated peptide, BP21, alleviates hypothermia and vascular hyperpermeability during anaphylactic reactions in a mouse model of anaphylaxis via the direct binding of a Tyr-Lys-Asp-Gly sequence in the peptide to PAF. In this study, we investigated the effect of BP21 on in vivo anaphylactic hypotension. Results showed that BP21 significantly inhibited anaphylactic hypotension in a dose-dependent manner, with peak severity being reached within 20 minutes. Adrenaline, which is the recommended first line treatment for anaphylactic patients, did not inhibit anaphylactic hypothermia. The combined administration of BP21 with adrenaline inhibited both hypotension and hypothermia, even at both low doses, more effectively compared with solo administration of BP21 or adrenaline. These results suggested that BP21 could potentially be a novel anti-anaphylactic agent for targeting PAF in vivo.

Changing the history of anaphylaxis mortality statistics through the World Health Organization's International Classification of Diseases-11

We review the history of the classification and coding changes for anaphylaxis and provide current and perspective information in the field. In 2012, an analysis of Brazilian data demonstrated undernotification of anaphylaxis-related deaths because of the difficulties of coding using the International Classification of Diseases, 10th Revision. This work triggered strategic international actions supported by the Joint Allergy Academies and the International Classification of Diseases World Health Organization (WHO) leadership to update the classification of allergic disorders for the International Classification of Diseases, 11th Revision (ICD-11), which resulted in construction of the pioneer "Allergic and hypersensitivity conditions" chapter. The usability of the new framework has been tested by evaluating the same data published in 2012 from the ICD-11 perspective. Coding accuracy was much improved, reaching 95% for definite anaphylaxis. As the results were provided to the WHO Mortality Reference Group, coding rules have been changed, allowing anaphylaxis to be recorded as an underlying cause of death in official mortality statistics. The mandatory use of ICD-11 from January 2022 for documenting cause of death could have 2 immediate consequences: (1) the reported number of anaphylaxis-related deaths might increase because of more appropriate coding and (2) the cross-sectional and longitudinal mortality data generated might ultimately lead to a better understanding of anaphylaxis epidemiology and improved health policies directed at reducing anaphylaxis-related mortality.

Paired acute-baseline serum tryptase levels in perioperative anaphylaxis: An observational study

BACKGROUND

Anaphylaxis is recognized mainly through clinical criteria, which may lack specificity or relevance in the perioperative setting. The transient increase in serum tryptase has been proposed since 1989 as a diagnostic tool. Sampling for well-defined acute and baseline determinations has been recommended. We assessed the performance of four proposed algorithms with tightly controlled time frames for tryptase sampling, their robustness with inadequate sampling times, and the possible use of mature tryptase determination.

METHODS

A retrospective study was performed on 102 adult patients from the Aix-Marseille University Hospitals who had experienced a perioperative hypersensitivity reaction clinically suggesting anaphylaxis. EAACI and ICON criteria were used to diagnose anaphylaxis. Mature and total serum tryptase levels were measured.

RESULTS

Based on EAACI guidelines, clinical diagnostic criteria for anaphylaxis were found in 76 patients and lacking in 26. The most effective algorithm was the international consensus recommendation of 2012 that acute total tryptase levels should be greater than ([1.2×baseline tryptase] + 2] μg/L to be considered a clinically significant rise. In our cohort, this algorithm achieved 94% positive predictive value (PPV), 53% negative predictive value (NPV), 75% sensitivity, 86% specificity, and a Youden's index value of 0.61. A detectable acute mature tryptase level showed lower sensitivity, particularly in patients with acute total tryptase levels lower than 16 μg/L. Acute tryptase levels varied as a function of the clinical severity of anaphylaxis.

CONCLUSION

Total tryptase levels in serum discriminated between nonanaphylactic and anaphylactic events in a perioperative setting when acute and baseline levels were collected and analyzed by the consensus algorithm.

Histamine, histamine receptors, and anti-histamines in the context of allergic responses

Histamine is a bioactive amine which is considered a key player in the allergic response. Thus, histamine receptor blockers (antihistamines) play an important role in the treatment of a number atopic diseases such as allergic rhinitis, conjunctivitis, and acute and chronic forms of urticaria. Histamine is produced by immune cells but also by bacteria in the gut. Beyond its role in the acute allergic response, histamine exerts numerous effects by binding to its 4 pleiotropic G-protein coupled histamine receptors. Here, we describe the roles of these histamine receptors and antihistamines in the human system, clinical applications, side effects, and novel concepts for the usage of antihistamines with different specificity based on guidelines and recommendations.

Statement of novelty: This review provides an overview of histamine receptors and links it to clinical relevance of antagonizing their action in clinical routine.

Diagnosis and management of drug-induced anaphylaxis in children: An EAACI position paper

Drug hypersensitivity reactions (DHR) constitute a major and common public health problem, particularly in children. One of the most severe manifestations of DHR is anaphylaxis, which might be associated with a life-threatening risk. During those past decades, anaphylaxis has received particularly a lot of attention and international consensus guidelines have been recently published. Whilst drug-induced anaphylaxis is more commonly reported in adulthood, less is known about the role of drugs in pediatric anaphylaxis. Betalactam antibiotics and non-steroidal anti-inflammatory drugs are the most commonly involved drugs, probably related to high prescription rates. Diagnosis relies on the recognition of symptoms pattern and is based on complete allergic workup, particularly including skin tests and/or specific IgE. However, the real diagnostic value of those tests to diagnose immediate reactions in children remains not well defined for a significant number of the drugs. Generally, a drug provocation test is discussed to confirm or exclude an immediate-onset drug-induced hypersensitivity. Although avoidance of the incriminated drug (and related drug) is the rule, rapid desensitization is useful in selected subgroups of patients. There is a need for large, multicentric studies, to evaluate the real diagnostic value of the currently available skin tests. Moreover there is also a need to develop new diagnostic tests in the future to improve the management of these children.

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.

Emergency anaphylaxis protocols: A cross-sectional analysis of general practice surgeries and pharmacies in both the urban and rural setting in Ireland

Background: The incidence of anaphylaxis appears to be increasing worldwide with cases in the community outnumbering those in the hospital setting. General practice (GP) surgeries and pharmacies, based in the community, are often the first point of contact for many patients suffering from anaphylaxis.

Objectives: To determine if studied GP surgeries and pharmacies have an anaphylaxis protocol on site and have access to an anaphylaxis kit; to explore GP’s and pharmacists’ personal experiences with management of anaphylaxis.

Methods: A cross-sectional, questionnaire-based study was performed examining anaphylaxis protocols in a sample of general practices and pharmacies from some counties in Ireland. This consisted of a sample from rural and urban settings. The study commenced in October 2014.

Results: Nineteen of 24 GPs (79%) and 9 (29%) pharmacies had an anaphylaxis protocol (P < 0.001). Twenty-four (100%) GP practices and 12 pharmacies (39%) surveyed had an anaphylaxis kit on site. Twelve GPs (50%) had treated a patient with anaphylaxis in the surgery while 8 (33%) had treated a patient in the community. One pharmacist (3%) had witnessed anaphylaxis in practice. Two pharmacies and one GP had been contacted by local businesses to alert them to a case of anaphylaxis.

Conclusion: In contrast to national and international guidelines only 79% of GPs and 29% of pharmacies in this study from Ireland had an anaphylaxis protocol onsite.

Underuse of Epinephrine for Pediatric Anaphylaxis Victims in the Emergency Department: A Population-based Study

Purpose

Epinephrine is a key drug for treating anaphylaxis; however, its underuse is still a significant issue worldwide. The objective of this study was to compare epinephrine use between pediatric and adult patients who were treated with anaphylaxis in the emergency department (ED).

Methods

The data were retrieved from the National Sample Cohort of South Korea, which contains claim data from the National Health Insurance Service. We included patients who visited the ED with a discharge code of anaphylaxis between 2004 and 2013. We assessed prescription information of epinephrine, antihistamine and systemic steroid, previous medical history and discharge disposition from the ED. The study population was categorized based on age at the visit.

Results

A total of 175 pediatric and 1,605 adult patients with anaphylaxis were identified. Only 42 (24%) of the pediatric patients were treated with epinephrine, while 592 (36.9%) of the adult patients were treated with epinephrine (P = 0.001). Furthermore, the pediatric patients were less likely to be treated with systemic steroid than the adult patients (6.9% vs. 12.3%, P = 0.047). The odds ratios for the administration of epinephrine relative to the baseline in the 19-65 age group were 0.34 (95% confidence interval [CI], 0.15–0.67), 0.56 (95% CI, 0.28–1.03) and 0.79 (95% CI, 0.45–1.33) in the < 7, 7–12 and 13–18 age groups, respectively.

Conclusions

The pediatric patients with anaphylaxis experienced a lower rate of epinephrine injection use than the adult patients and the injection use decreased as age decreased.

Changes in emergency department concordance with guidelines for the management of stinging insect-induced anaphylaxis: 1999-2001 vs 2013-2015

BACKGROUND

Changes in emergency department (ED) concordance with guidelines for the management of stinging insect-induced anaphylaxis (SIIA) are not known.

OBJECTIVE

To describe temporal changes in ED concordance with guidelines for the management of SIIAs.

METHODS

We analyzed data from 2 multicenter retrospective studies of patients with stinging insect-related acute allergic reactions seen in 1 of 14 North American EDs during 2 periods: 1999 through 2001 and 2013 through 2015. Visits were identified similarly across studies (eg, using International Classification of Diseases, Ninth Revision, Clinical Modification codes 989.5, 995.0, and 995.3). Anaphylaxis was defined as an acute allergic reaction with involvement of at least 2 organ systems or hypotension. We compared concordance between periods with 4 guideline recommendations: (1) treatment with epinephrine, (2) discharge prescription for epinephrine auto-injector, (3) referral to an allergist/immunologist, and (4) instructions to avoid the offending allergen.

RESULTS

We compared 182 patients with SIIA during 1999 to 2001 with 204 during 2013 to 2015. Any treatment with epinephrine (before arrival to the ED or in the ED) increased over time (30% vs 49%; P < .001). Prescriptions for epinephrine auto-injector at discharge increased significantly (34% vs 57%; P < .001), whereas documentation of referral to an allergist/immunologist decreased (28% vs 12%; P = .002), and instructions to avoid the offending allergen did not change (23% vs 24%; P = .94). Receipt of at least 3 guideline recommendations increased over time; however, the comparison was not statistically significant (10% vs 16%; P = .15).

CONCLUSION

During the nearly 15-year study interval, we observed increased ED concordance with epinephrine-related guideline recommendations for the management of SIIA. Reasons for the decrease in allergy/immunology referrals merit further study.

Cefuroxime-induced anaphylaxis with prominent central nervous system manifestations: A case report

Cefuroxime is a second-generation cephalosporin antibiotic that causes immediate hypersensitivity reactions, ranging from mild urticaria to severe anaphylactic shock. Anaphylactic reactions typically involve multiple systems, most notably, the skin and the respiratory and cardiovascular systems. Here, we report the unusual case of a patient who presented with oral cefuroxime-induced anaphylaxis with prominent neurologic manifestations. To identify the drug responsible for the anaphylaxis, we performed skin tests. Based on positive skin-prick test results, the diagnosis of cefuroxime-induced anaphylaxis was confirmed. Therefore, we suggest that clinicians should consider the possibility of a drug-induced anaphylactic reaction when neurologic but not cutaneous symptoms are present. The skin-prick test is a safe and useful diagnostic tool to confirm this kind of immediate drug hypersensitivity.

Food-induced fatal anaphylaxis: From epidemiological data to general prevention strategies

BACKGROUND

Anaphylaxis hospitalizations are increasing in many countries, in particular for medication and food triggers in young children. Food-related anaphylaxis remains an uncommon cause of death, but a significant proportion of these are preventable.

AIM

To review published epidemiological data relating to food-induced anaphylaxis and potential risk factors of fatal and/or near-fatal anaphylaxis cases, in order to provide strategies to reduce the risk of severe adverse outcomes in food anaphylaxis.

METHODS

We identified 32 published studies available in MEDLINE (1966-2017), EMBASE (1980-2017), CINAHL (1982-2017), using known terms and synonyms suggested by librarians and allergy specialists.

RESULTS

Young adults with a history of asthma, previously known food allergy particularly to peanut/tree nuts are at higher risk of fatal anaphylaxis reactions. In some countries, cow's milk and seafood/fish are also becoming common triggers of fatal reactions. Delayed adrenaline injection is associated with fatal outcomes, but timely adrenaline alone may be insufficient. There is still a lack of evidence regarding the real impact of these risk factors and co-factors (medications and/or alcohol consumption, physical activities, and mast cell disorders).

CONCLUSIONS

General strategies should include optimization of the classification and coding for anaphylaxis (new ICD 11 anaphylaxis codes), dissemination of international recommendations on the treatment of anaphylaxis, improvement of the prevention in food and catering areas, and dissemination of specific policies for allergic children in schools. Implementation of these strategies will involve national and international support for ongoing local efforts in relationship with networks of centres of excellence to provide personalized management (which might include immunotherapy) for the most at-risk patients.

Evaluation of the Potential Risk Factors for Drug-Induced Anaphylaxis in Adult Patients

AIM

To investigate the potential risk factors in patients who have experienced anaphylaxis from drugs.

METHOD

The study included 281 adult patients (median age 40 years; 76.5% female) who experienced immediate types of hypersensitivity reaction to a drug. The patients were divided into an anaphylaxis group and a nonanaphylaxis group. The anaphylaxis group was diagnosed according to the criteria of the World Allergy Organization. Skin testing with culprit drugs was performed. In the nonanaphylaxis group, drug provocation tests were performed with culprit drugs, including aspirin or diclofenac, to determine nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. Atopy was determined by skin prick tests with the common inhalant allergens. Patients' demographics, clinical features, and baseline tryptase and total IgE levels were compared between the 2 groups.

RESULTS

The median interval between the last reaction in the patient's history and the study evaluation was 7 months (range 1-120 months). In 52.3% of the patients, reactions were defined as anaphylaxis. The most common culprit drugs were NSAIDs (56.9%) and β-lactams (34.7%). The culprit drugs were used parenterally in 13.2% of the patients. 34.9% of the patients had comorbid diseases and 24.6% used additional drugs, the most common being antihypertensives (10%). Atopy was determined in 28.8% and 28.1% of the patients were smokers. The median serum level of baseline tryptase and total IgE was 3.5 µg/L and 77 kU/L, respectively. In 46.3% of the patients, skin tests with culprit drugs were positive and the positivity ratio was higher in the anaphylaxis group (p = 0.002). Anapyhlaxis was more common in patients who were: hypertensive, atopic, using angio-tensin-converting enzyme inhibitors/angiotensin receptor blockers, and received the culprit drug parenterally (p = 0.034, p = 0.04, p = 0.03, p = 0.035, p = 0.013, and p < 0.001). In the multivariate analysis, it was observed that the parenteral usage of the drug and the presence of atopy were significantly higher in the anaphylaxis group (p < 0.001, odds ratio [OR] = 20.05, confidence interval [CI] 4.75-88.64; p = 0.012, OR = 2.1, CI 1.17-3.74). Age, smoking, family history, and serum levels of baseline tryptase and total IgE did not differ between groups.

CONCLUSION

The parenteral route and atopy increase the risk of drug-induced anaphylaxis. IgE-mediated sensitivity to the culprit drug seems to facilitate anaphylaxis.

Evaluation of the left venticular systolic function with the measurement of global longitudinal strain by Speckle tracking echocardiography in anaphylaxis

Background

It is not known how cardiac functions are affected during anaphylaxis.

Objective

Our aim was to measure the cardiac functions shortly after an anaphylaxis attack using a new technique that detects subclinical left ventricular dysfunction.

Methods

Patients in our hospital who experienced anaphylaxis and urticaria (control group) due to any cause were included in the study. Tryptase levels were measured on the third hour of the reaction and 6 weeks later. Left ventricular systolic functions were evaluated with global strain measurement using echocardiography, approximately 4 hours and 6-week post reaction.

Results

Twelve patients were included in the anaphylaxis group (83.3% female; mean age, 43.25 ± 9.9 years). The causes of anaphylaxis were drug ingestion (n = 11) and venom immunotherapy. Eight of the anaphylactic reactions (66.7%) were severe and in 9 reactions (75%) tryptase levels increased. In the anaphylaxis group, strain values measured shortly after anaphylaxis were significantly lower than those calculated 6 weeks later (p < 0.001) and tryptase levels significantly increased (p = 0.002). The strain values measured both shortly after anaphylaxis and 6 weeks later did not differ according to severity of anaphylaxis. In severe anaphylaxis, tryptase levels during anaphylaxis and 6 weeks later were significantly higher (p = 0.019, p = 0.035). The control group evidenced no differences regarding strain and tryptase levels measured at reaction and 6 weeks later. At reaction, in the anaphylaxis group, the tryptase levels were higher and the strain values were lower than those in the urticaria group (p = 0.007, p = 0.003).

Conclusion

Cardiac dysfunction may develop during an anaphylaxis independent of severity of reaction.

The Epidemiology of Anaphylaxis

Anaphylaxis is a dramatic expression of systemic allergy. The lifetime prevalence of anaphylaxis is currently estimated at 0.05-2 % in the USA and ~3 % in Europe. Several population-specific studies have noted a rise in the incidence, particularly in the hospitalizations and ER visits due to anaphylaxis. The variable signs and symptoms that constitute the diagnostic criteria for anaphylaxis, the differences in diagnostic algorithms, and the limitations in the current coding systems have made summarizing epidemiologic data and comparing study results challenging. Nevertheless, across all studies, the most common triggers continue to be medications, food, and venom. Various risk factors for more severe reactions generally include older age, history of asthma, and having more comorbid diseases. Interesting seasonal, geographic, and latitude differences have been observed in anaphylaxis prevalence and incidence rates, suggesting a possible role of vitamin D and sun exposure in modifying anaphylaxis risk. While the incidence and prevalence of anaphylaxis appear to be increasing in certain populations, the overall fatality rate remains relatively low.

Increasing trends of anaphylaxis-related events: an analysis of anaphylaxis using nationwide data in Taiwan, 2001-2013

Background

Anaphylaxis is a severe, potentially fatal, and systemic allergic reaction. Previous studies document increasing trends in incidence rates of anaphylaxis-related events in Western countries, yet little is known about the incidence and trend of anaphylaxis in Asia. In this study, we aimed to determine time trends in incidence rates of anaphylaxis-related events in Taiwan from 2001 through 2013.

Methods

We utilized medical claims data from the National Health Insurance Research Databases in Taiwan. We identified anaphylaxis-related events (ICD-9-CM-codes: 995.0, 995.60–995.69, 999.41–999.42, and 999.49) and calculated incidence rates. Poisson regression models were applied to examine trends and incidence rates.

Results

A total of 2496 patients (mean age, 45.11 years; 56% male) with first-time anaphylaxis were identified during 34,430,000 person-years of observation time. The overall incidence of anaphylaxis was 7.25 (95% confidence interval (CI) = 6.97–7.53) per 100,000 person-years, increasing from 4.79 in 2001 to 8.20 in 2013, with an incidence rate ratio (IRR) of 1.05 (95%CI = 1.04–1.06). Over the 13-year period, the increasing trends were found in incident diagnosis of anaphylaxis-related outpatient or emergency department visits (IRR = 1.06, 95%CI = 1.05–1.08) and admissions to intensive care units (IRR = 1.06, 95%CI = 1.03–1.10), whereas the trends in incidence of anaphylaxis-related hospitalizations remained steady. The proportion of patients requiring hospitalizations among all patients with anaphylaxis (p_{_trend} = 0.01), as well as the proportion requiring intensive care treatment among patients who were hospitalized (p_{_trend} = 0.01), both increased with age.

Conclusion

The incidence rate of anaphylaxis in Taiwan has increased at an average rate of 5% annually since 2001, paralleling the rising trends in several Western countries.

Electronic supplementary material

The online version of this article (10.1186/s40413-018-0202-7) contains supplementary material, which is available to authorized users.

Anaphylactic cardiovascular collapse and Kounis syndrome: systemic vasodilation or coronary vasoconstriction?

The first reported human anaphylactic death is considered to be the Pharaoh Menes death, caused by a wasp sting. Currently, anaphylactic cardiovascular events represent one of most frequent medical emergencies. Rapid diagnosis, prompt and appropriate treatment can be life saving. The main concept beyond anaphylaxis lies to myocardial damage and ventricular dysfunction, thus resulting in cardiovascular collapse. Cardiac output depression due to coronary hypoperfusion from systemic vasodilation, leakage of plasma and volume loss due to increased vascular permeability, as well as reduced venous return, are regarded as the main causes of cardiovascular collapse. Clinical reports and experiments indicate that the human heart, in general, and the coronary arteries, in particular, could be the primary target of the released anaphylactic mediators. Coronary vasoconstriction and thrombosis induced by the released mediators namely histamine, chymase, tryptase, cathepsin D, leukotrienes, thromboxane and platelet activating factor (PAF) can result to further myocardial damage and anaphylaxis associated acute coronary syndrome, the so-called Kounis syndrome. Kounis syndrome with increase of cardiac troponin and other cardiac biomarkers, can progress to heart failure and cardiovascular collapse. In experimental anaphylaxis, cardiac reactions caused by the intracardiac histamine and release of other anaphylactic mediators are followed by secondary cardiovascular reactions, such as cardiac arrhythmias, atrioventricular block, acute myocardial ischemia, decrease in coronary blood flow and cardiac output, cerebral blood flow, left ventricular developed pressure (LVdp/dtmax) as well as increase in portal venous and coronary vascular resistance denoting vascular spasm. Clinically, some patients with anaphylactic myocardial infarction respond satisfactorily to appropriate interventional and medical therapy, while anti-allergic treatment with antihistamines, corticosteroids and fluid replacement might be ineffective. Therefore, differentiating the decrease of cardiac output due to myocardial tissue hypoperfusion from systemic vasodilation and leakage of plasma, from myocardial tissue due to coronary vasoconstriction and thrombosis might be challenging during anaphylactic cardiac collapse. Combined antiallergic, anti-ischemic and antithrombotic treatment seems currently beneficial. Simultaneous measurements of peripheral arterial resistance and coronary blood flow with newer diagnostic techniques including cardiac magnetic resonance imaging (MRI) and myocardial scintigraphy may help elucidating the pathophysiology of anaphylactic cardiovascular collapse, thus rendering treatment more rapid and effective.

EAACI Position paper on the standardization of nasal allergen challenges

Nasal allergen challenge (NAC) is an important tool to diagnose allergic rhinitis. In daily clinical routine, experimentally, or when measuring therapeutic success clinically, nasal allergen challenge is fundamental. It is further one of the key diagnostic tools when initiating specific allergen immunotherapy. So far, national recommendations offered guidance on its execution; however, international divergence left many questions unanswered. These differences in the literature caused EAACI to initiate a task force to answer unmet needs and find a consensus in executing nasal allergen challenge. On the basis of a systematic review containing nasal allergen challenges of the past years, task force members reviewed evidence, discussed open issues, and studied variations of several subjective and objective assessment parameters to propose a standardized way of a nasal allergen challenge procedure in clinical practice. Besides an update on indications, contraindications, and preparations for the test procedure, main recommendations are a bilaterally challenge with standardized allergens, with a spray device offering 0.1 mL per nostril. A systematic catalogue for positivity criteria is given for the variety of established subjective and objective assessment methods as well as a schedule for the challenge procedure. The task force recommends a unified protocol for NAC for daily clinical practice, aiming at eliminating the previous difficulty of comparing NAC results due to unmet needs.