Relationship Between Anaphylaxis and Use of Beta-Blockers and Angiotensin-Converting Enzyme Inhibitors: A Systematic Review and Meta-Analysis of Observational Studies

Pearls for practice from the 2023 joint task force anaphylaxis practice parameter

PURPOSE OF REVIEW

To share important highlights on the management of anaphylaxis from the latest 2023 practice parameter.

RECENT FINDINGS

The 2023 Allergy Immunology Joint Task Force on Practice Parameters (JTFPP) anaphylaxis practice parameter provides updated anaphylaxis guidance. Criteria for the diagnosis of anaphylaxis are reviewed. The parameter highlights that while anaphylaxis is not more severe in younger children, age-specific symptoms can vary. Activation of emergency medical services may not be required in patients who experience prompt resolution of symptoms following epinephrine use and caregivers are comfortable with observation. For children weighing <15 kg, the anaphylaxis parameter suggests the clinician may prescribe either the 0.1 mg or the 0.15 mg epinephrine autoinjector, with the 0.3 mg autoinjector prescribed for those weighing 25 kg or greater. In patients with heart disease, discontinuing or changing beta blockers and/or angiotensin converting enzyme inhibitors may pose a larger risk for worsened cardiovascular disease compared with risk for severe anaphylaxis with medication continuation. Furthermore, in patients with a history of perioperative anaphylaxis, shared decision-making based on diagnostic testing and clinical history is recommended prior to repeat anesthesia use. Beyond the recent parameter update, novel contemporary therapies can decrease risk of community anaphylaxis.

SUMMARY

The 2023 JTFPP Anaphylaxis Guidelines offer up-to-date guidance for the diagnosis and management of anaphylaxis in infants, children, and adults.

Anaphylaxis in Practice: A Guide to the 2023 Practice Parameter Update

This review summarizes new research developments and clinical practice recommendations for the diagnosis and management of anaphylaxis presented in the Joint Task Force on Practice Parameters 2023 Anaphylaxis practice parameter Update. It is intended to serve as a high-level summary of the 2023 practice parameter, which makes clinically impactful recommendations based on evidence that has emerged since the 2015 practice parameter. We invite clinicians to explore the full 2023 practice parameter to understand the research methods and underlying evidence that have informed the recommendations summarized here. There are new and evolving diagnostic criteria for anaphylaxis, rules for defining elevated tryptase levels, and recognition of signs and symptoms particular to infants and toddlers. The administration of epinephrine should not be used as a surrogate to diagnose anaphylaxis. Risk factors for anaphylaxis should be assessed on a case-by-case basis. Patient counseling and shared decision-making are essential to support patients' treatment decisions and capacity to manage the risk of anaphylaxis at home and in other community settings. Activation of emergency medical services after home epinephrine administration may not be required in all cases, and patients should be engaged in shared decision-making to determine when home management may be appropriate.

Identifying patients at risk of anaphylaxis

Anaphylaxis is an acute, potentially fatal, systemic hypersensitivity reaction that warrants prompt diagnosis and management. It continues to be challenging to anticipate who may be at risk of a severe, life-threatening allergic reaction. Anaphylaxis can be caused by a range of allergens, such as certain foods, medications, latex, insect stings, etc. Cofactors that augment the severity of clinical symptoms and increase the risk of poor outcomes include exercise, stress, infectious diseases, underlying mast cell disease, active allergic disease such as asthma, advanced age, intake of certain medications, history of previous anaphylaxis, and delayed or missed administration of adrenaline. According to the European Anaphylaxis Registry, food is the major elicitor of anaphylaxis, especially eggs, cow milk, and nuts, in children and adolescents. Reaction to insect venom has also been noted in young adulthood. Early recognition of signs and symptoms and prompt treatment are crucial in anaphylaxis management to avoid serious and even fatal outcomes. It is crucial for both individuals and clinicians to identify the cause of anaphylaxis. Biomarkers of anaphylaxis, such as histamine, tryptase, platelet activation factor (PAF), chymase, carboxypeptidase A3, dipeptidyl peptidase I (DPPI), basogranulin, CCL-2, hsa-miR-451a, may be useful in diagnosis and management. The purpose of this review article is to present a comprehensive overview of current evidence and expert opinions regarding the risk factors that predispose individuals to anaphylaxis. Additionally, it provides insights into potential biomarkers and genetic markers for accurate diagnosis and management. This review underscores the significance of expert guidance in enhancing patient outcomes and enabling self-management of anaphylactic episodes.

Anaphylaxis: A 2023 practice parameter update

This practice parameter update focuses on 7 areas in which there are new evidence and new recommendations. Diagnostic criteria for anaphylaxis have been revised, and patterns of anaphylaxis are defined. Measurement of serum tryptase is important for diagnosis of anaphylaxis and to identify underlying mast cell disorders. In infants and toddlers, age-specific symptoms may differ from older children and adults, patient age is not correlated with reaction severity, and anaphylaxis is unlikely to be the initial reaction to an allergen on first exposure. Different community settings for anaphylaxis require specific measures for prevention and treatment of anaphylaxis. Optimal prescribing and use of epinephrine autoinjector devices require specific counseling and training of patients and caregivers, including when and how to administer the epinephrine autoinjector and whether and when to call 911. If epinephrine is used promptly, immediate activation of emergency medical services may not be required if the patient experiences a prompt, complete, and durable response. For most medical indications, the risk of stopping or changing beta-blocker or angiotensin-converting enzyme inhibitor medication may exceed the risk of more severe anaphylaxis if the medication is continued, especially in patients with insect sting anaphylaxis. Evaluation for mastocytosis, including a bone marrow biopsy, should be considered for adult patients with severe insect sting anaphylaxis or recurrent idiopathic anaphylaxis. After perioperative anaphylaxis, repeat anesthesia may proceed in the context of shared decision-making and based on the history and results of diagnostic evaluation with skin tests or in vitro tests when available, and supervised challenge when necessary.

Adrenaline autoinjectors for Australian out-of-hospital anaphylaxis: where to from here?

Intramuscular adrenaline autoinjectors are accepted as first-line treatment for out-of-hospital anaphylaxis but face ongoing issues of patient nonadherence related to drug expiry, availability, correct administration, and public recognition of the disease. Adrenaline is associated with possible harms in patients with defined comorbidities but is still considered preferable. Further research and policy is required to facilitate the effective treatment of anaphylaxis.

Comparison of recent anaphylaxis diagnostic criteria in real life: Can more patients be diagnosed as having anaphylaxis?

Introduction

In 2020, World Allergy Organization (WAO) updated their diagnostic criteria for anaphylaxis, which differed as a result from the National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network (NIAID/FAAN) criteria which were still used in the 2021 update of the European Academy of Allergy and Clinical Immunology (EAACI) anaphylaxis guideline. Our aim was to evaluate and to compare both diagnostic criteria and attempt to identify factors affecting severity of anaphylaxis.

Methods

The medical records of the patients who were evaluated with suspected anaphylaxis at 3 medical centers in Türkiye between 2014 and 2021, and underwent a detailed diagnostic work-up, were analyzed retrospectively. Diagnosis of anaphylaxis was evaluated based on the WAO 2020 and EAACI 2021 and NIAID/FAAN diagnostic criteria. The severity of anaphylaxis was determined according to the WAO systemic allergic reaction grading system. Grade 5 anaphylaxis was defined as having respiratory failure, collapse/hypotension, loss of consciousness. Patients' demographic and clinical characteristics were further analyzed depending on the severity of the reaction.

Results

One thousand and six patients were evaluated and 232 patients without a convincing diagnosis of anaphylaxis were excluded from the study. The remaining 774 patients (70.6% female, median [Inter quartile range (IQR) 25-75] age: 42 [33-52]) were included for further examination. Anaphylaxis was diagnosed in 729 (94.2%) patients meeting both criteria whereas 35 patients (4.5%) with isolated laryngeal involvement and 10 (1.3%) patients with isolated respiratory involvement were only diagnosed according to the WAO 2020 criteria. Twenty-three patients (3.0%) had a diagnosis of indolent systemic mastocytosis. Mastocytosis was related to grade 5 anaphylaxis [p = 0.022, OR (CI) = 2.9 (1.1-7.6)]. Venom allergy was a risk factor for grade 5 anaphylaxis among those for whom an eliciting allergen could be determined [p = 0.03, OR (CI) = 2.7 (1.1-6.8)]. For drug induced anaphylaxis, parenteral route of drug administration and proton pump inhibitor (PPI) allergy were considered as risk factors for grade 5 anaphylaxis [p < 0.001, OR (CI) = 6.5 (2.5-17.0); p = 0.011, OR (CI) = 10.3 (1.6-63.3)].

Conclusion

This multicenter study demonstrated that both criteria identified the majority of patients with anaphylaxis, but the WAO 2020 diagnostic criteria identified an additional 6%. Hymenoptera stings, PPI allergy, parenteral drug administration, and underlying mastocytosis were associated with more severe episodes.

Extrinsic and Intrinsic Modulators of Anaphylaxis

The severity of anaphylaxis is determined by many factors. The allergenic source as well as the age of the affected individual and the route of allergen exposure encompass the major contributors of the clinical outcome. Moreover, the severity can be modulated further by intrinsic and extrinsic factors. Among these, the genetic predisposition, certain comorbidities such as uncontrolled asthma, and hormonal fluctuations have been proposed as intrinsic and antihypertensive medications or physical activity as extrinsic factors. Recent advances have highlighted immunologic pathways that may exacerbate the response to allergens through receptors on mast cells, basophils, platelets, and other granulocytes. Atopy, platelet-activating factor acetylhydrolase deficiency, hereditary alpha tryptasemia, and clonal mast cell disorders are examples associated with genetic alterations that may predispose to severe anaphylaxis. Identifying risk factors that lower the threshold of reactivity or increase the severity of multisystem reactions is important in the management of this patient population.

Cofactors in food anaphylaxis in adults

Around 25% to 50% of food-induced allergic reactions in adults cause anaphylaxis, and epidemiologic evidence suggests that food is the most common cause of anaphylaxis. Reaction severity is unpredictable, and patients will often experience reactions of variable severity, even to an identical exposure (both dose and allergen). A common explanation for this phenomenon has been the impact of "cofactors"-factors that might contribute to reaction severity independent of the allergen exposure. Cofactors can influence reaction severity in 2 ways: either by reducing the reaction threshold (ie, the dose needed to trigger any symptoms) so that patients have no symptoms in the absence of the cofactor and only react with the cofactor present, or by increasing reaction severity such that individuals have only mild symptoms in the absence of the cofactor, but a more severe reaction when the cofactor is present. Indeed, the same patient may have reactions with different cofactors or even need more than one cofactor to develop a severe reaction. Cofactors reportedly play a role in approximately 30% of anaphylaxis reactions in adults. Exercise, nonsteroidal, anti-inflammatory drugs, alcohol, and sleep deprivation are the most frequent cofactors reported. Routine evaluation of the possible involvement of cofactors is essential in managing patients with food anaphylaxis: in patients with a suggestive history but a negative oral food challenge, cofactors should be taken into account to provide appropriate advice to reduce the risk of future anaphylaxis.

Updates and Recent Advances on Venom Immunotherapy

Purpose of Review

Venom immunotherapy has been utilized to treat Hymenoptera venom allergy since the 1920s. Over the last century, significant advances in the fields of immunology and genetics have led to improvements in the practice of venom immunotherapy. This review encompasses recent advances in the use of venom immunotherapy to provide precise, patient-centered care.

Recent Findings

Research about the mechanism of action of venom immunotherapy continues to highlight the modification of both the innate and adaptive immune systems. Molecular techniques have allowed for the identification of specific venom allergens to improve the diagnostic accuracy and safety of venom immunotherapy. Research continues to support the safety of accelerated schedules which can impact the cost, adherence, and quality of life for patients receiving this treatment modality. Finally, significant advances have led to the elucidation of risk factors that place patients at risk for reactions during and after venom immunotherapy. Creation of risk profiles for venom-allergic patients can thus inform the process of immunotherapy in order to provide personalized and precise care.

Summary

Significant progress in the use of venom immunotherapy makes the practice a dynamic and active field for continued research. Future research needs to build on these recent advances to continue to optimize and enhance this life-saving treatment.

Impact of Outpatient Antihypertensive Medication Use on Epinephrine Resistance in Anaphylaxis

BACKGROUND

There has been an increase in allergy-related emergency department (ED) visits over the past several years. Underlying cardiovascular disease or respiratory disease and concurrent beta blocker or angiotensin-converting enzyme inhibitor use have been identified as potential risk factors for severe or refractory anaphylactic reactions. Conflicting evidence exists regarding the association between antihypertensive (AH) use and the incidence of refractory anaphylaxis.

OBJECTIVE

The purpose of this study was to determine the incidence of refractory anaphylaxis in patients presenting to the ED while prescribed select AH medications outpatient.

METHODS

This was a retrospective cohort study of all adult and pediatric patients presenting to the ED between February 16, 2021, and August 31, 2021, with a diagnosis of anaphylaxis. The primary objective was to compare the proportion of patients experiencing refractory anaphylaxis that were prescribed versus not prescribed AH medications in the outpatient setting.

RESULTS

A total of 101 patients were treated for anaphylaxis in the ED during the study timeframe with 13 patients in the AH group and 88 patients in the no AH group. There was no difference in the incidence of refractory anaphylaxis between groups (0% vs 9%; p=0.48). Significantly fewer patients in the AH group required any epinephrine doses compared to the no AH group (38% vs 88%; p<0.001).

CONCLUSIONS

Outpatient use of select AH medications was not associated with an increased incidence of refractory anaphylaxis in patients presenting to the ED.

Wings and stings: Hymenoptera on vacation

Traveling to different regions, one might encounter a species to which they have a known allergy, or other related and unrelated species. A first-time systemic reaction can occur while on vacation, even in those with previous asymptomatic stings. Three main groups of Hymenoptera are responsible for most sting reactions. Honey bee species are virtually identical around the world. Among social wasps (family Vespidae), the yellowjacket (genus Vespula and Dolichovespula) and hornet (genus Vespa) venoms have almost complete cross-reactivity, whereas paper wasp (genus Polistes) venoms show only partial cross-reactivity with other vespid venoms. Venom immunotherapy (VIT) confers 80% to 95% protection against related insects, though isolated species of paper wasps and yellowjackets exist in every country that may be distinct from the ones at home. Those allergic to imported fire ants (genus Solenopsis) in the United States should not react to other ant species around the world. Stinging ants belong to several unrelated subfamilies in different geographic regions, which do not have cross-reactive venom. The chances of encountering specific species of Hymenoptera at a traveler's destination vary by location, planned activities, and season. In this article, we discuss special considerations for traveling, including distribution of stinging insects around the world, risk factors for more severe reactions, ways to prepare for a trip, and when allergist examination or treatment may be helpful before travel.

Anaphylaxis: Advances in the Past 10 Years

In the past 10 years, anaphylaxis has grown into its own special area of study within Allergy-Immunology, both at the bench and at the bedside. This review focuses on some of the most clinically relevant advances over the past decade. These include simplified and more inclusive diagnostic criteria for adults and children, uniform definition of biphasic anaphylaxis, and improved systems for objective severity grading. Studies reported in the past decade have led to improved understanding of normal and abnormal regulation of mast cell function, translating into better diagnostic and therapeutic approaches to patients with anaphylaxis. Research has provided improved recognition and treatment of mast cell disorders and has identified a new condition, hereditary α-tryptasemia, that may impact anaphylactic syndromes. We have learned to recognize new causes (α-gal), new pathways (Mas-related G protein-coupled receptor-X2), and many risk factors for severe anaphylaxis. The stability of epinephrine in autoinjectors was reported to be very good for several years after the labeled expiry date, and it can tolerate freezing and thawing. Repeated and prolonged exposure to excessive heat leads to degradation of epinephrine activity. New treatments to prevent severe anaphylaxis have been described, using new ways to block the IgE receptor or modulate intracellular signaling pathways.

Anaphylaxis in elderly people

PURPOSE OF REVIEW

Anaphylaxis is common in old-age adults but is insufficiently understood by physicians, and may be underdiagnosed. This review discusses the specificities of anaphylaxis in this age group and stresses the importance of adrenaline in its management.

RECENT FINDINGS

Data from the European Anaphylaxis Registry on elderly patients is a major finding. Other findings include the prevention of possible anaphylactic reactions in coronavirus disease 2019 vaccination as well as some new epidemiologic data.

SUMMARY

The most common risk factors are hymenoptera venom and food and drug allergy. Cardiovascular symptoms are the most important ones to reverse in old-age adults, especially due to the multiple comorbidities. Anaphylaxis in old-age adults has a more severe outcome than in younger ones. Polypharmacy is a specific factor to be considered. The Airway, Breathing, Circulation, Disability, Exposure (ABCDE) algorithm is applicable in all clinical emergencies for immediate assessment and treatment, and should be considered for all patients. Adrenaline is the mainstay of the management of the condition. There are no absolute contraindications to the prescription of self-injectable adrenaline in elderly individuals at risk of anaphylaxis.

Risk factors for severe reactions in food allergy: Rapid evidence review with meta-analysis

This rapid review summarizes the most up to date evidence about the risk factors for severe food-induced allergic reactions. We searched three bibliographic databases for studies published between January 2010 and August 2021. We included 88 studies and synthesized the evidence narratively, undertaking meta-analysis where appropriate. Significant uncertainties remain with respect to the prediction of severe reactions, both anaphylaxis and/or severe anaphylaxis refractory to treatment. Prior anaphylaxis, an asthma diagnosis, IgE sensitization or basophil activation tests are not good predictors. Some molecular allergology markers may be helpful. Hospital presentations for anaphylaxis are highest in young children, yet this age group appears at lower risk of severe outcomes. Risk of severe outcomes is greatest in adolescence and young adulthood, but the contribution of risk taking behaviour in contributing to severe outcomes is unclear. Evidence for an impact of cofactors on severity is lacking, although food-dependent exercise-induced anaphylaxis may be an exception. Some medications such as beta-blockers or ACE inhibitors may increase severity, but appear less important than age as a factor in life-threatening reactions. The relationship between dose of exposure and severity is unclear. Delays in symptom recognition and anaphylaxis treatment have been associated with more severe outcomes. An absence of prior anaphylaxis does not exclude its future risk.

Adult anaphylaxis: A state-of-the-art review

Anaphylaxis is the most severe among acute allergic diseases and potentially life threatening. Despite its increasing frequency and related burden, it remains often underdiagnosed and improperly managed. Its multisystemic involvement, protean clinical manifestations and its rapid onset are contributory factors. In recent years new acquisitions have shed light into its pathogenesis pathways (and related biomarkers), triggers, factors increasing its severity, along with peculiar clinical manifestations. These breakthrough discoveries have contributed to phenotyping and endotyping this disease, possibly paving the way to a personalized approach which is not available at present. Moreover, to disseminate awareness and standardize diagnostic criteria and management practices, several guidelines and consensus reports, albeit mainly intended for specialist care, have been issued. We here discuss the latest issues in the field of anaphylaxis from the perspective of the emergency and/or internal medicine physician, so to improve its early recognition and treatment in the acute setting and favor allergology referral to implement therapeutical and preventive strategies, such as allergen identification in unclear cases and desensitizing therapies when available (e.g., for Hymenoptera venom allergy).

Managing anaphylaxis in adults

Anaphylaxis is a severe and potentially life-threatening allergic reaction. The recognition and treatment of anaphylaxis remains complex and an area of continued professional development for health professionals. Prompt recognition of anaphylaxis and its subsequent treatment and management by the multidisciplinary team, including nurses and allied health professionals, is key as this increases the patient's chances of survival. Evidence-based clinical information on managing anaphylaxis will enable health professionals to provide safer patient care.

Anaphylaxis viewed by experts: unmet needs

PURPOSE OF REVIEW

The purpose of the review is to identify unmet needs in the management of anaphylaxis, covering aspects such as epidemiology, diagnosis, treatment and prevention.

RECENT FINDINGS

Redefinition of clinical diagnostic criteria may allow a better identification of anaphylaxis. International diagnostic coding system improvement will be major step for future policies and epidemiological studies. Digital health can aid in managing anaphylaxis.

SUMMARY

Anaphylaxis is a medical emergency; current data show that frequently identification of the reaction, acute and long-term management, are not optimal. Therefore, there is a need to implement strategies to improve the situation. This review has identified unmet needs in anaphylaxis regarding aspects such as epidemiology, severity scoring, definition and diagnostic criteria, anaphylaxis in infants and toddlers, cofactors, biomarkers, long-term management, undertreatment and availability of epinephrine autoinjectors. Strategies focused on education, legislation, digital health and research are proposed.

β-blockers and ACE inhibitors are not a risk factor for severe systemic sting reactions and adverse events during venom immunotherapy

Background

There is controversy whether taking β‐blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT).

Methods

In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking β‐blockers or ACEI show more systemic AE during VIT compared to patients without such treatment.

Results

In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took β‐blockers, 11.9% ACEI, 5.0% β‐blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43–1.22, p = 0.25). The severity of the initial sting reaction was not affected by the intake of β‐blockers or ACEI (OR: 1.14, 95% CI: 0.89–1.46, p = 0.29). In total, 210 (17.7%) patients were re‐stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took β‐blockers, none an ACEI.

Conclusions

This trial provides robust evidence that taking β‐blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; Clinicaltrials.gov number, NCT04269629).

Diagnosing, managing and preventing anaphylaxis: Systematic review

BACKGROUND

This systematic review used the GRADE approach to compile evidence to inform the European Academy of Allergy and Clinical Immunology's (EAACI) anaphylaxis guideline.

METHODS

We searched five bibliographic databases from 1946 to 20 April 2020 for studies about the diagnosis, management and prevention of anaphylaxis. We included 50 studies with 18 449 participants: 29 randomized controlled trials, seven controlled clinical trials, seven consecutive case series and seven case-control studies. Findings were summarized narratively because studies were too heterogeneous to conduct meta-analysis.

RESULTS

It is unclear whether the NIAID/FAAN criteria or Brighton case definition are valid for immediately diagnosing anaphylaxis due to the very low certainty of evidence. There was also insufficient evidence about the impact of most anaphylaxis management and prevention strategies. Adrenaline is regularly used for first-line emergency management of anaphylaxis but little robust research has assessed its effectiveness. Newer models of adrenaline autoinjectors may slightly increase the proportion of people correctly using the devices and reduce time to administration. Face-to-face training for laypeople may slightly improve anaphylaxis knowledge and competence in using autoinjectors. We searched for but found little or no comparative effectiveness evidence about strategies such as fluid replacement, oxygen, glucocorticosteroids, methylxanthines, bronchodilators, management plans, food labels, drug labels and similar.

CONCLUSIONS

Anaphylaxis is a potentially life-threatening condition but, due to practical and ethical challenges, there is a paucity of robust evidence about how to diagnose and manage it.

Management of anaphylaxis due to COVID-19 vaccines in the elderly

Older adults, especially men and/or those with diabetes, hypertension, and/or obesity, are prone to severe COVID‐19. In some countries, older adults, particularly those residing in nursing homes, have been prioritized to receive COVID‐19 vaccines due to high risk of death. In very rare instances, the COVID‐19 vaccines can induce anaphylaxis, and the management of anaphylaxis in older people should be considered carefully. An ARIA‐EAACI‐EuGMS (Allergic Rhinitis and its Impact on Asthma, European Academy of Allergy and Clinical Immunology, and European Geriatric Medicine Society) Working Group has proposed some recommendations for older adults receiving the COVID‐19 vaccines. Anaphylaxis to COVID‐19 vaccines is extremely rare (from 1 per 100,000 to 5 per million injections). Symptoms are similar in younger and older adults but they tend to be more severe in the older patients. Adrenaline is the mainstay treatment and should be readily available. A flowchart is proposed to manage anaphylaxis in the older patients.

Update on Insect Sting Anaphylaxis

PURPOSE OF REVIEW

This review describes improvement in diagnostic accuracy, prediction of outcomes, identifying high-risk factors, and refinements of treatment that continue to evolve over the past 5-10 years.

RECENT FINDINGS

The risk of anaphylaxis is relatively low (< 5%) in patients with previous large local reactions or strictly cutaneous systemic reactions, but much higher in those with moderate-to-severe anaphylaxis (40%-70%) or mastocytosis (> 90%). Use of recombinant venom allergens and basophil activation tests may improve diagnostic accuracy. Elevated serum tryptase (and possible mastocytosis) occurs in 10% of patients with insect sting allergy, and in 25% of those with hypotensive reactions. Rush VIT is proven safe and rapidly effective. There are known high-risk factors that justify treatment beyond 5 years. Diagnostic accuracy and prediction of risk have improved in recent years. There are still knowledge gaps related to prediction and management of risk with current diagnostic and therapeutic modalities.

Critical Care Management of the Patient With Anaphylaxis: A Concise Definitive Review

OBJECTIVES

Anaphylaxis is a rapidly progressive life-threatening syndrome manifesting as pruritus, urticaria, angioedema, bronchospasm and shock. The goal of this synthetic review is to provide a practical, updated approach to the evaluation and management of this disorder and associated complications.

DATA SOURCES

A MEDLINE search was conducted with the MeSH of anaphylaxis, anaphylactic reaction, anaphylactic shock, refractory anaphylaxis and subheadings of diagnosis, classification, epidemiology, complications and pharmacology. The level of evidence supporting an intervention was evaluated based on the availability of randomized studies, expert opinion, case studies, reviews, practice parameters and other databases (including Cochrane).

STUDY SELECTION

Selected publications describing anaphylaxis, clinical trials, diagnosis, mechanisms, risk factors and management were retrieved (reviews, guidelines, clinical trials, case series) and their bibliographies were also reviewed to identify relevant publications.

DATA EXTRACTION

Data from the relevant publications were reviewed, summarized and the information synthesized.

DATA SYNTHESIS

This is a synthetic review and the data obtained from a literature review was utilized to describe current trends in the diagnosis and management of the patient with anaphylaxis with a special emphasis on newer evolving concepts of anaphylaxis endotypes and phenotypes, management of refractory anaphylaxis in the ICU setting and review of therapeutic options for the elderly patient, or the complicated patient with severe cardiorespiratory complications. Most of the recommendations come from practice parameters, case studies or expert opinions, with a dearth of randomized trials to support specific interventions.

CONCLUSION

Anaphylaxis is a rapidly progressive life-threatening disorder. The critical care physician needs to be familiar with the diagnosis, differential diagnosis, evaluation, and management of anaphylaxis. Skilled intervention in ICUs may be required for the patient with complicated, severe, or refractory anaphylaxis.

World allergy organization anaphylaxis guidance 2020

Anaphylaxis is the most severe clinical presentation of acute systemic allergic reactions. The occurrence of anaphylaxis has increased in recent years, and subsequently, there is a need to continue disseminating knowledge on the diagnosis and management, so every healthcare professional is prepared to deal with such emergencies. The rationale of this updated position document is the need to keep guidance aligned with the current state of the art of knowledge in anaphylaxis management. The World Allergy Organization (WAO) anaphylaxis guidelines were published in 2011, and the current guidance adopts their major indications, incorporating some novel changes. Intramuscular epinephrine (adrenaline) continues to be the first-line treatment for anaphylaxis. Nevertheless, its use remains suboptimal. After an anaphylaxis occurrence, patients should be referred to a specialist to assess the potential cause and to be educated on prevention of recurrences and self-management. The limited availability of epinephrine auto-injectors remains a major problem in many countries, as well as their affordability for some patients.

β-Blockers and angiotensin-converting enzyme inhibitors with sublingual immunotherapy: are risks related to individual product safety profile?

PURPOSE OF REVIEW

The objective of this article is to review the available literature regarding the risks associated with sublingual immunotherapy and angiotensin-converting enzyme (ACE) inhibitors or β-blocker use. It also evaluates for any differences in these risks among the available sublingual immunotherapy (SLIT) tablets.

RECENT FINDINGS

A literature search was conducted in PubMed to identify peer-reviewed articles using the following keywords: anaphylaxis, ACE inhibitor, β-blocker, and sublingual immunotherapy. Minimal data exist regarding their safety of SLIT in patients concomitantly taking ACE inhibitors or β-blockers. The adverse reaction rates seem similar between SLIT products.

SUMMARY

A risk-versus-benefit discussion should be communicated with the patient taking a β-blocker before beginning SLIT but automatic denial of SLIT to these patients is not warranted.

The Journal of Allergy and Clinical Immunology: In Practice 2019 Highlights

This article provides highlights of the clinically impactful original studies and reviews published in The Journal of Allergy and Clinical Immunology: In Practice in 2019 on the subjects of anaphylaxis, asthma, dermatitis, drug allergy, food allergy, immunodeficiency, immunotherapy, rhinitis/sinusitis, and urticaria/angioedema/mast cell disorders. Within each topic, practical aspects of diagnosis and management are emphasized. Treatments discussed include lifestyle modifications, allergen avoidance therapy, positive and negative effects of pharmacologic therapy, and various forms of immunologic and desensitization management. We designed this review to help readers consolidate and use this extensive and practical knowledge for the benefit of their patients.

Anaphylaxis for Internists: Definition, Evaluation, and Management, with a Focus on Commonly Encountered Problems

Anaphylaxis is an acute systemic allergic reaction that can be life threatening. In adults, the most common causes of anaphylaxis are foods, drugs, and insect stings. This article reviews the definition, classification, evaluation, differential diagnosis, prognosis, complications, and management of anaphylaxis. Tailored for internists, the article focuses on anaphylactic medication allergies. It provides a guide to optimally evaluate and manage patients with antibiotic allergy using a simple, rapid risk stratification technique, graded antibiotic challenge (test dose), and/or allergist-guided drug desensitization. It also reviews other causes of anaphylaxis that internists are likely to encounter, and an approach to their management.

Contraindications to immunotherapy: a global approach

BACKGROUND

Recommendations on contraindications to allergen immunotherapy (AIT) have been independently developed by National and International Societies/Academies. AIT contraindications are mainly based on case reports, case-series, or experts' opinion, while evidence-based information is limited. The aim of the present review was to describe existing guidelines on contraindications to AIT and to highlight differences between them.

MAIN BODY

An extended review of the literature regarding contraindications to AIT for respiratory allergy and venom hypersensitivity was performed. Furthermore, Societies and Academies registered in the World Allergy Organization and EAACI databases, were asked for additional information. Only AIT guidelines published under official auspicies were included. A large heterogeneity among the various recommendations on contraindications was registered. Common contraindications to most of the guidelines were: lack of adherence, pregnancy before the start of AIT, the use of beta-blockers, certain age groups, uncontrolled asthma, autoimmune diseases and malignancies.

CONCLUSION

As new data arise, revisions might soon be needed allowing AIT in the cases of patients treated with ACE inhibitors and beta-blockers, in elderly patients and in patients with concomitant autoimmune diseases and neoplasias in remission. The decision to prescribe AIT is always tailor-made, balancing risk vs benefit. Creating globally accepted guidelines would help Allergologists in their decision making.