Anaphylaxis: A 2023 practice parameter update

Reductions in medical visits and hospitalizations following berotralstat initiation in patients with hereditary angioedema in the United States

BACKGROUND

Hereditary angioedema (HAE) is a rare disease characterized by unpredictable recurrent, debilitating, and potentially fatal attacks of subcutaneous and submucosal tissue swelling.

OBJECTIVE

To evaluate all-cause, angioedema-related, and HAE attack-related medical visits and hospitalizations before and after initiation of berotralstat long-term prophylaxis (LTP) for patients with HAE in the United States.

METHODS

This retrospective pre-post analysis used Komodo's Healthcare Map claims data to identify patients who initiated berotralstat (December 2020 to December 2022). The first entry for berotralstat dispensing was defined as the index date. Inclusion criteria comprised patients aged at least 12 years at index with at least 6 months of continuous insurance eligibility pre-index and evidence consistent with HAE pre-index (International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes D84.1, D68.2, or T78.3x; medication use [on-demand or LTP]; or presence of diagnostic HAE laboratory tests). Rates of all-cause, angioedema-related, and HAE attack-related medical visits per person-year were compared post-index vs pre-index using rate ratios with 95% CIs and P values from generalized estimating equation Poisson regression models with robust SEs. Study limitations included the inability to distinguish HAE types and the uncertainty of whether a dispensed medication was consumed or taken as prescribed.

RESULTS

The study population included 260 patients treated with berotralstat (mean age = 39.7 years; 74.2% female). After berotralstat initiation, there were significant decreases in the rates of all-cause health care resource utilization (HRU): all-cause inpatient (IP) visits decreased by 34% (P = 0.037) and all-cause outpatient/emergency department (OP/ED) visits decreased by 14% (P = 0.005). There were also significant decreases in rates of angioedema-related HRU (IP visits: 52%, P = 0.001; OP/ED visits: 44%, P < 0.001) as well as HAE attack-related HRU (IP visits: 60%, P < 0.001; OP/ED visits: 50%, P < 0.001). Use of on-demand medications decreased significantly after berotralstat initiation (32%, P = 0.002). Results were similar among subgroups of patients defined by HAE treatment history, including patients who were LTP-experienced (n = 126) and LTP-naive but on-demand treatment-experienced (n = 67).

CONCLUSIONS

Prophylactic treatment of HAE with berotralstat was associated with significant reductions in all-cause HRU, including decreases to angioedema-related and HAE attack-related medical visits, hospitalizations, and administration of on-demand treatment.

Hypersensitivity reactions to contrast media: Part 2. Prevention of recurrent hypersensitivity reactions in adults. Updated guidelines by the ESUR Contrast Media Safety Committee

Hypersensitivity reactions to contrast media are infrequent and can occur either within the first 60 min following their intravascular administration (immediate reactions) or at a later time point (non-immediate reactions). Most hypersensitivity reactions are mild or moderate, while severe reactions are rare (less than 1 in every 10,000 administrations). After any moderate or severe immediate adverse reaction, serum tryptase must be measured within 1-4 h from the onset of symptoms and at least 24 h after symptoms have disappeared to confirm a hypersensitivity reaction. At least for all moderate-to-severe hypersensitivity reactions, the patient should be referred to a drug allergy specialist for an allergy evaluation with a panel of contrast media, and optionally, all hypersensitivity reactions when local drug allergy specialist capacity allows. Selecting an alternative contrast medium based on practical experience is challenging due to its high and variable cross-reactivity; therefore, the best option is to choose an alternative based on the results of an allergy evaluation. This approach is safer and more effective than premedication for preventing recurrent hypersensitivity reactions. KEY POINTS: Question What is the optimal strategy in clinical practice to prevent recurrent hypersensitivity reactions in adults who previously experienced a hypersensitivity reaction to contrast media? Findings Serum tryptase should be measured within 1-4 h after a moderate or severe reaction, and at least all moderate or severe hypersensitivity reactions should be referred to an allergologist. Clinical relevance Management strategies should be adapted to the type and severity of the reaction, as well as the urgency of required re-administration. Changing from the culprit contrast agent to another molecule with differing side-chains is more effective than premedication.

Hypersensitivity reactions to contrast media: Part 1. Management of immediate and non-immediate hypersensitivity reactions in adults. Updated guidelines by the ESUR Contrast Media Safety Committee

Hypersensitivity reactions to iodine-based, gadolinium-based and ultrasound contrast agents are a heterogeneous group that occur infrequently and can be classified as either immediate or non-immediate. In imaging, most are mild or moderate, while severe reactions are very rare. A standardized risk assessment and close patient monitoring are crucial. In addition to liberal use of supportive treatment by oxygen and volume expansion, the main drugs for treatment of individual reactions include intramuscular adrenaline and H1-antihistamines, with limited indications for short-acting β2-agonists (SABA) like salbutamol or albuterol. As these reactions occur infrequently, these situations often create stress and confusion. During treatment, the stability or progression of the reaction should be constantly assessed, assigning a specific task to each team member. In addition, detailed documentation and correct classification of the severity of such reactions will help improve the risk management in future imaging studies. Regular hands-on training for all personnel involved in managing these reactions is mandatory. To help, the ESUR Contrast Media Safety Committee has reviewed the literature on hypersensitivity reactions and updated its guidance on how to appropriately manage, treat, and document immediate and non-immediate hypersensitivity reactions to contrast media in adults. KEY POINTS: Question Hypersensitivity reactions to contrast media may require immediate action to prevent further damage to the patient. Guidance on management would help improving preparedness. Findings Clear treatment protocols with cards or flowcharts are mandatory. Intramuscular adrenaline is the most important drug for treatment. Documentation should be agent-specific and standardized. Clinical relevance The ESUR Contrast Media Safety Committee has updated its guidance on how to appropriately manage, treat, and document immediate and non-immediate hypersensitivity reactions to contrast media in adults.

Want to help your patients with food allergy anxiety? Do proximity challenges!

Excessive anxiety regarding the potential for accidental and fatal cross-contamination is very common among patients and families with food allergy and contributes significantly to burden, reduced quality of life, and poorer management. In their landmark paper published nearly a decade ago, Dr Chitra Dinakar and colleagues recommended that food allergists incorporate proximity food challenges such as smelling or touching an allergen into regular clinical practice to improve patient knowledge regarding safety and relative risk and reduce anxiety. Such proximity challenges are akin to the exposure tasks routinely used to treat anxiety in cognitive-behavioral therapy, the first-line psychosocial intervention for anxiety disorders. Exposure is a highly evidence-based therapy technique in which patients-guided and encouraged by their providers-directly and strategically confront a feared object, situation, or activity. Anxiety eventually diminishes and erroneous beliefs are corrected when exposures happen repeatedly in the absence of the feared negative outcome. Following a summary of the history and evidence base for exposure in both the psychiatric and food allergy literature, we review several considerations related to conducting in-office proximity challenges. Topics include in-office assessment of food allergy anxiety and medically unnecessary avoidance; choosing appropriate, individualized proximity challenges based on patient presentation; and practical considerations in carrying out in-office proximity challenges to maximize benefits to anxious patients.

Laboratory Animal Allergy

ABSTRACT

Ranging from mild respiratory allergy to anaphylaxis, laboratory animal allergy (LAA) can adversely affect an individual's health and career. LAA can be prevented through a hierarchy of controls. However, workers remain at risk as many, if not most, workplaces have not fully adopted needed prevention practices. To address this risk, organizations should use a multidisciplinary leadership team. Along with participation on the leadership team, occupational medicine physicians should oversee a medical surveillance program that identifies workers with LAA including incident cases, as well as workers with LAA who are symptomatic in the workplace. One indication that medical surveillance may be effective in identifying incident cases is that it is detecting prevalent cases, usually in the range of 10%-20% or higher. Programs with lower detection rates of prevalent cases should adjust their approach to medical surveillance. The results of medical surveillance, including the incidence and prevalence of LAA, should be shared within the organization and used to guide the use of controls. Periodic self-audits are recommended to better protect workers by identifying and addressing opportunities for program improvement.

Integrated phase I pharmacokinetics and pharmacodynamics of epinephrine administered through sublingual film, autoinjector, or manual injection

BACKGROUND

Epinephrine is the first-line treatment for anaphylaxis and is administered through intramuscular or subcutaneous injection. AQST-109, a sublingual film containing the prodrug epinephrine, was developed as an alternative delivery method for treating severe allergic reactions, including anaphylaxis.

OBJECTIVE

To compare the pharmacokinetics (PK) and pharmacodynamics (PD) of epinephrine after the administration of AQST-109 with those of epinephrine delivered by manual intramuscular injection and epinephrine autoinjectors.

METHODS

Data were integrated from 2 randomized, open-label, phase I crossover trials that evaluated the PK and PD of epinephrine in 54 healthy volunteers. They had no previous medical conditions and were delivered either AQST-109 12 mg or 0.3 mg EpiPen, 0.3 mg generic EpiPen, 0.3 mg Auvi-Q, and 0.3 mg manual intramuscular injection.

RESULTS

AQST-109 yielded comparable epinephrine PK and exposure to both manual intramuscular injections and epinephrine autoinjectors. The median time to maximum concentration (Tmax) for AQST-109 was 15 minutes, compared with EpiPen (10 minutes), generic EpiPen (15 minutes), Auvi-Q (30 minutes), and manual intramuscular injection (50 minutes). There was also an early, rapid, and consistent increase in systolic blood pressure, diastolic blood pressure, and heart rate after the administration of AQST-109.

CONCLUSION

AQST-109 delivered epinephrine with PK and PD results within the bracketed range of approved intramuscular products. AQST-109 has promise as an innovative, needle-free, nondevice, portable, and orally delivered alternative for first-line treatment of type I allergic reactions, including anaphylaxis.

Management and Prevention of Hypersensitivity Reactions to Radiocontrast Media: A Consensus Statement from the American College of Radiology and the American Academy of Allergy, Asthma & Immunology

Intravenous iodinated contrast media (ICM) is widely used in the United States, and it is imperative to provide guidance on the management of adverse reactions to ICM as well as the preparation, planning, and potential premedication for patients with previous reactions. Currently there is a discordance between the American College of Radiology Contrast Manual, which recommends premedication to prevent repeat hypersensitivity reactions to ICM, and the Anaphylaxis 2020 Practice Parameters Update, which recommends against routine administration of glucocorticoids and/or antihistamines to prevent anaphylaxis with prior ICM hypersensitivity reactions. A task force of experts from radiology who are also members of the American College of Radiology Committee on Drugs and Contrast Media and expert allergists/immunologists including members of the Adverse Reactions to Drugs, Biologics and Latex Committee of American Academy of Allergy, Asthma & Immunology evaluated the scientific evidence to develop consensus recommendations that are endorsed by both organizations. The task force took into account the strength of evidence and balanced the potential risks of recurrent reactions with those of premedication and product avoidance when making these recommendations to improve and standardize the care of patients who experience or have a history of reaction to ICM. © Radiological Society of North America and American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc on behalf of American Academy of Allergy, Asthma & Immunology and by Radiological Society of North America. All rights are reserved, including those for text and data mining, AI training, and similar technologies. This paper was jointly developed by The Journal of Allergy and Clinical Immunology: In Practice, Radiology and jointly published by Elsevier Inc and Radiological Society of North America. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. Either citation can be used when citing this article. Keywords: Contrast allergy, Contrast hypersensitivity, Iodinated contrast allergy, Iodinated contrast hypersensitivity, Anaphylaxis, Contrast skin testing, Contrast switching, Contrast reaction, Delayed contrast reaction, Immediate contrast reaction.

Anaphylaxis in children: Latest insights

Background: The diagnosis and management of anaphylaxis in pediatric populations can be a particularly formidable challenge due to its variable definitions and atypical symptom presentation, which can often masquerade as other conditions. This complexity often leads to delays in early recognition and timely intervention. Most pediatric anaphylaxis guidelines emphasize the importance of identifying and avoiding triggers, ensuring accurate dosing and prompt administration of epinephrine to prevent severe complications. There is also growing scientific interest in strategies to intervene early in food allergy development to prevent allergies and protect infants and children from severe allergic reactions. Objective: This report aimed to review key aspects of the pathophysiology, epidemiology, management, and prevention of anaphylaxis in the pediatric population. Also, approved treatment modalities and future research to treat and prevent anaphylactic reactions are discussed. Methods: A review of the medical literature was conducted by using terms that included anaphylaxis, severe allergic reaction, pediatric, prevalence, desensitization, and immunotherapy. Results: Food allergies remain the leading trigger of pediatric anaphylaxis, followed by Hymenoptera venom, whereas drug allergies are less common in children compared with adults. A review of the literature underscores the importance of recognizing early signs and symptoms of anaphylaxis, particularly in preverbal infants, of identifying and eliminating key triggers and of prompt epinephrine administration in the immediate management of pediatric anaphylaxis. Advances in oral immunotherapy and other treatments (e.g., biologics) provide new management options. Notably, anti-immunoglobulin E therapy with omalizumab has shown substantial protection against reactions to accidental food exposure in children as young as 1 year old and with food allergy. Conclusion: This report explores critical aspects of anaphylaxis that affect allergic diseases in infants and children. Gaining a deeper understanding of age-specific triggers and the diverse symptoms of anaphylaxis will significantly enhance diagnosis, treatment, and prevention strategies, ultimately improving the timeliness of interventions. Recent approvals of novel therapies for food allergies, along with promising developments for future treatment and prevention of anaphylaxis in pediatric populations, hold exciting potential for better management of these conditions.

Neurocognitive manifestation after treatment of pediatric severe anaphylaxis

BACKGROUND

Anaphylaxis is a common, severe, and life-threatening allergic reaction that occurs rapidly after exposure to an allergen which can affect multiple systems in the body. In rare cases, it may lead to additional neurological manifestations that are poorly understood.

CASE PRESENTATION

We present a case of a 14-year-old boy who experienced severe anaphylaxis necessitating airway intervention and admission to critical care. While his initial presentation and treatment aligned with current standards, he subsequently developed prolonged neurological deficits, including weakness, prosopagnosia, amnesia, and loss of basic functions, during an extended recovery period.

CONCLUSION

This rare neurological manifestation following anaphylaxis may be overlooked by many clinicians. Therefore, it is imperative to highlight this potential complication to improve the management of patients experiencing anaphylaxis.

Food allergy endotypes revisited

In the last century, food allergy has become recognized as an increasingly prevalent and heterogeneous condition. Advances in biomedical technology have revealed complex genetic, environmental, immune, and metabolic pathways underlying the pathogenesis of food-allergic disorders. These findings permit classification of distinct food allergy endotypes with unique pathophysiologic features. In this review, we suggest that these endotypes of food-allergic disorders should be defined on the basis of (1) whether or not the allergic antibody IgE plays an essential role in disease pathogenesis, (2) the molecular features of the allergen (protein vs carbohydrate), and (3) the molecular markers associated with prognosis, severity, or clinical presentation. Beyond these broad categories, additional subtypes with unique mechanistic characteristics are discussed.

Characteristics and Outcomes of Anaphylaxis in Emergency Department Visits Among Older Adults

BACKGROUND

Limited data exist on anaphylaxis characteristics and outcomes in older adults.

OBJECTIVE

To compare triggers, presentation, management, and outcomes of anaphylaxis emergency department (ED) visits between older adults (≥65 y) and younger adults (18-64 y) in a prehospital setting and the ED.

METHODS

This cohort study included ED visits among adults meeting anaphylaxis diagnostic criteria from April 2008 to December 2022. Visit characteristics and outcomes were analyzed by age group using χ2 analysis and multivariable logistic regression.

RESULTS

Among 1,422 patient visits, 212 (14.9%) involved older adults. Compared with younger adults, visits among older adults were more likely to involve anaphylaxis from medications (34.0% vs 21.3%; odds ratio [OR] 1.85; 95% confidence interval [95% CI] 1.34-2.55) and intravenous contrast (13.2% vs 5.6%; OR 2.50; 95% CI 1.55-4.04). Older adult visits had increased odds of severe anaphylaxis (adjusted odds ratio [OR] 1.57; 95% CI 1.12-2.21), including endotracheal intubation (aOR 6.24; 95% CI 2.69-14.48) and admission to the hospital or intensive care unit (aOR 1.78; 95% CI 1.19-2.67). Older adult visits were also more likely to arrive via Emergency Medical Services (EMS) (56.1% vs 34.0%; OR 2.56; 95% CI 1.89-3.46), but less likely to receive EMS-administered epinephrine (26.0% vs 32.4%; aOR 0.46; 95% CI 0.27-0.77).

CONCLUSIONS

Visits among older adults had increased odds of anaphylaxis from medications and IV contrast, cardiovascular symptoms, and more severe outcomes, including intubation and intensive care unit admission. Improved EMS epinephrine administration and prehospital guidelines could enhance outcomes for older adults with anaphylaxis.

Benefits of Epinephrine for Anaphylaxis Outweigh Potential Harm-A Safety Review

Anaphylaxis is a potentially life-threatening allergic reaction that can progress quickly, and although fatal anaphylaxis is very rare, treatment should be given as soon as possible. The recommended first-line treatment for anaphylaxis is intramuscular (IM) epinephrine. Yet epinephrine for anaphylaxis is underused, which can have deleterious, or even tragic, consequences. Although fear of self-injection substantially affects adherence, hesitancy to use epinephrine for anaphylaxis may be linked to the common unsubstantiated perception that epinephrine is dangerous. Therefore, the objective of this narrative review is to describe the safety of epinephrine when administered for the treatment of anaphylaxis. Cardiovascular adverse events (AEs) are the greatest safety concern with epinephrine because of its known effects on cardiac output and vasoconstriction. Cardiovascular events and overdose are significantly more likely to occur with accidental intravenous bolus administration than IM administration. Although serious AEs have been reported with IM epinephrine, and there are potential risk factors for cardiovascular AEs for some patients, there are no absolute contraindications for its use in a life-threatening situation. Appropriately dosed and administered epinephrine should engender no fear of use for anaphylaxis. The potential harm of delaying or withholding epinephrine treatment for anaphylaxis far outweighs the potential risk of AEs.

Development of a validated, updated North American pediatric food allergy anaphylaxis management plan

BACKGROUND

Current North American anaphylaxis action plans (AAPs) lack updated anaphylaxis guidelines that conditionally recommend "immediate activation of emergency medical services" after epinephrine use for patients experiencing a "prompt, complete, and durable response" to treatment. This offers a contextualized "watchful waiting" approach. AAPs may not include newly approved nasal epinephrine or differentiate anaphylaxis presentations by age.

OBJECTIVE

To develop an updated AAP.

METHODS

A prototype AAP was iteratively developed incorporating a "watchful waiting" approach, the nasal epinephrine option, and age-specific anaphylaxis symptom presentations among a team of anaphylaxis experts and patient and advocacy stakeholders to assess medical accuracy, readability, clarity, and bias. This underwent validated assessment of decisional acceptability, decisional conflict, and decisional self-efficacy in a sample of stakeholders with children at risk for anaphylaxis, or at risk themselves.

RESULTS

We developed a 2-page written plan (Flesch-Kincaid reading level 5.9) explaining management choices for severe and nonsevere reactions, indications for watchful waiting vs emergency medical services activation after epinephrine use, updated medication options, and age-based symptom differentiation. A total of 229 stakeholders assessed the AAP, noting good acceptability, high decisional self-efficacy (mean score 86.2/100, SD 15.9), and moderate decisional conflict (mean score 43.7/100, SD 18.8). Decisional conflict was unrelated to past anaphylaxis or epinephrine use. Information content was clear and sufficiently explained options with balanced and without a "best choice" bias. Overall, 86% of the respondents would recommend using this AAP.

CONCLUSION

This is the first validated AAP incorporating preference-sensitive post-epinephrine management options consistent with updated North American guidelines, newly approved nasal epinephrine, and age-specific anaphylaxis presentation.

Perioperative Anaphylaxis: A Systematic Approach to Evaluate High-Risk Drug Allergy

Determining the etiology of perioperative anaphylaxis is a challenging task, as multiple medications are often administered simultaneously during anesthesia. This is compounded by the paucity of validated skin testing. While drug challenges are the definitive means of assessing for IgE-mediated drug allergy, they must be weighed with the risk of severe reaction. As such, multidisciplinary collaboration is warranted to ensure drug provocation testing is performed thoughtfully and safely. Here, we present a case of an 18-year-old male with juvenile kyphosis who underwent anesthesia prior to spinal fusion surgery. He was given intravenous fentanyl, propofol, dexamethasone, remifentanil, tranexamic acid, methadone, and cefazolin. Additionally, iodine, chlorhexidine, and tincture of benzoin were applied topically. Shortly after the start of anesthesia and prior to incision, he developed bronchospasm, hypoxia, hypotension, and pulseless electrical activity with a return of spontaneous circulation following cardiopulmonary resuscitation. A tryptase level drawn during the event was elevated at 23.7 μg/L (reference range: 0-11.4 μg/L). Months later, the patient underwent skin prick and intradermal testing in an allergy clinic, which was largely unrevealing for a culprit. Given the absence of validated predictive values for skin testing, drug provocation testing was performed with the patient admitted to the intensive care unit due to the high-risk nature of testing. Medications were selected for a challenge after multidisciplinary discussions with specialists in anesthesia and surgery based on the availability of alternative medications. Following negative drug provocation testing to intravenous dexamethasone, intravenous fentanyl, oral midazolam, intravenous methadone, and intravenous tranexamic acid, as well as topical challenges to chlorhexidine, iodine, and tincture of benzoin, the patient was instructed to continue to avoid cefazolin, propofol, and remifentanil and was able to subsequently undergo spinal fusion surgery safely. This case demonstrates a systematic approach for high-risk drug allergy testing that was facilitated by collaboration with allergy, intensive care, anesthesia, and surgery.

Updates in Food Anaphylaxis Management

The management of food allergy has evolved over the past several years with regulatory approval of food allergy therapeutics as well as the common practice of oral immunotherapy. Whether a patient or family chooses one of these therapies or avoidance, they are still considered at risk of reaction, and thus clinicians still need to stay up to date with the latest advancements in the management of anaphylaxis in patients with food allergy. This review will highlight some of these updates, starting with the definition, diagnosis, and classifications of anaphylaxis. It will then review the latest updates in the management of food anaphylaxis in the community. Finally, the review will discuss the latest in epinephrine including recommendations on epinephrine dosing and novel routes of epinephrine administration.

Infant and Toddler Peanut Oral Immunotherapy: Initiation Before Age 2 Increases Ad Libitum Peanut Consumption

BACKGROUND

Peanut oral immunotherapy (POIT) has promising potential of disease modification, but there are no studies to date evaluating high-dose POIT, leading to ad libitum (ad lib) consumption of peanut products, especially in children 6 months to 4 years of age.

OBJECTIVE

To report real-world outcomes of high-dose POIT in children 6 months to 4 years of age, including adverse events, achievement of ad lib consumption, and the impact of age on these outcome measures.

METHODS

Patients 6 months to 4 years of age with a diagnosis of peanut allergy were enrolled in a POIT protocol with a goal dose of 3000 mg. Demographics along with POIT and clinical outcomes 6 months after POIT are reported.

RESULTS

Sixty children, with a median age of 16 months, started POIT. Three (5%) were lost to follow-up, and 6 (10%) discontinued POIT because of recurrent adverse events or the inability to consume daily peanut protein. Fifty-one (85%) children completed POIT in a median of 7 months and were consuming ad lib peanut products for a duration of 6 months after completion of the POIT protocol. Sixteen (26.7%) children experienced a total of 22 adverse reactions during POIT. Initiating POIT before 24 months of age increased the likelihood of ad lib peanut consumption by an odds ratio of 11.69 (1.19-114.31, P = .035).

CONCLUSIONS

Our study demonstrates that high-dose POIT in infants and toddlers is well tolerated and can lead to ad lib introduction of dietary peanut products into the diet, especially if initiated before 2 years of age.

Parenteral Nutrition and Anaphylaxis: A Case Report and Literature Review

Parenteral nutrition (PN) is a high-risk therapy for patients unable to meet their nutritional needs enterally, carrying risks of hypersensitivity reactions, including anaphylaxis. We present the case of a patient with advanced gastric cancer and a distal subocclusive process that could not tolerate enteral nutrition. PN was initiated, but within five minutes, he developed severe allergic symptoms, which resolved completely after the discontinuation of PN and treatment with antihistamines and steroids. Although hypersensitivity reactions to PN are rare, they can be severe and potentially fatal. Intravenous fat emulsions (IVFEs) and multivitamin solutions are common allergens. This case highlights the need for heightened vigilance during PN administration and the importance of identifying potential allergens. Careful monitoring and individualized care are essential for patients receiving PN. Diagnostic methods are needed to identify specific allergens, prevent future reactions, and improve patient safety.

Discrepancies in anaphylaxis protocols across emergency medical services in the United States: Opportunities for improvement

BACKGROUND

Across the United States, there are significant inconsistencies in the protocols used by emergency medical services (EMS) in the prehospital treatment of anaphylaxis. These discrepancies include variations in the definition of anaphylaxis and treatment recommendations.

OBJECTIVE

To identify gaps in the recognition of anaphylaxis and to provide areas for improvement in prehospital management through an analysis of state-wide anaphylaxis protocols.

METHODS

States with mandatory or model state-wide protocols were included (total of 30). Each allergic reaction and/or anaphylaxis protocol was reviewed-emphasis was placed on the definitions used to identify reactions and treatment algorithms.

RESULTS

Of the 30 states, only 50% (15) included gastrointestinal symptoms in the definition of anaphylaxis and only 40% (12) included neurologic manifestations. In addition, 47% (14) used a 2-organ system definition. For anaphylactic reactions, 100% (30) of the protocols recommended diphenhydramine and epinephrine. However, 90% (27) recommended albuterol, if respiratory symptoms were present, and 60% (18) recommended steroids. Epinephrine was the first-line recommendation for anaphylaxis in 97% (29) of the protocols. Overall, 25 states (83%) allowed epinephrine autoinjectors and 17 (57%) provided autoinjectors.

CONCLUSION

Many EMS anaphylaxis protocols are incomplete and/or outdated. Many protocols do not consider gastrointestinal or neurologic manifestations. In addition, many contain outdated recommendations, including the use of steroids and first-generation antihistamines. Despite the convenience of epinephrine autoinjectors, many protocols do not permit or provide them. Given the frequency of EMS activation for allergic reactions, our communities would benefit from standardized protocols using current evidence-based guidelines for the management of anaphylaxis.

Management and Prevention of Hypersensitivity Reactions to Radiocontrast Media: A Consensus Statement From the American College of Radiology and the AAAAI

Intravenous iodinated contrast media (ICM) is widely used in the United States, and it is imperative to provide guidance on the management of adverse reactions to ICM as well as the preparation, planning, and potential premedication for patients with previous reactions. Currently there is a discordance between the American College of Radiology Contrast Manual, which recommends premedication to prevent repeat hypersensitivity reactions to ICM, and the Anaphylaxis 2020 Practice Parameters Update, which recommends against routine administration of glucocorticoids and/or antihistamines to prevent anaphylaxis with prior ICM hypersensitivity reactions. A task force of experts from radiology who are also members of the American College of Radiology Committee on Drugs and Contrast Media and expert allergists/immunologists including members of the Adverse Reactions to Drugs, Biologics and Latex Committee of American Academy of Allergy, Asthma & Immunology evaluated the scientific evidence to develop consensus recommendations that are endorsed by both organizations. The task force took into account the strength of evidence and balanced the potential risks of recurrent reactions with those of premedication and product avoidance when making these recommendations to improve and standardize the care of patients who experience or have a history of reaction to ICM.

The cause of perioperative hypersensitivity in adults and consequences of subsequent anesthesia

BACKGROUND

In the perioperative period, patients are exposed to many agents that may cause hypersensitivity reaction; so, finding the culprit drug is important for patient safety in the event of the need for repeat anesthesia.

AIM

Our aim was to share demographic data, clinical features, and diagnostic tests of patients who developed perioperative hypersensitivity (POH) and in whom the culprit drug was identified.

METHODS

Patients evaluated for POH between 2016 and 2024 were retrospectively analyzed. Results of anesthesia notes, agents used in anesthesia, skin prick test, and intradermal test (IDT) to determine the culprit drug were examined. Patients were interviewed by telephone and questioned about their reanesthesia status.

RESULTS

The files of 167,688 patients were analyzed; 405 patients were referred and tested for POH and 330 patients were excluded from the study because they had no history of POH or the culprit drug could not be identified. The study was completed with 75 patients. POH developed during the induction of anesthesia (I) in 18, maintenance (M) in 34, and at the end (E) in 23 patients. The median age was 48, out of which 89.3% (n = 67) were females. Reactions developed during genitourinary system surgery in 33.3% (n = 25), ear-nose-throat surgery in 17.3% (n = 13), and abdominal surgery in 17.3% (n = 13); anaphylaxis developed in 56% (n = 42) (I: 9; M: 21; E: 12); cutaneous involvement in 73.3% (n = 55); cardiovascular involvement in 41.3% (n = 31), respiratory system involvement in 56% (n = 42), and gastrointestinal involvement in 4% (n = 3); Brown grade 1 in 44% (n = 33) and grade 3 in 38.7% (n = 29); Ring and Messmer classification, grade 1 in 44% (n = 33); and cardiac arrest in five patients. For the distribution of culprit drugs: neuromuscular blocking agents (NMBAs) in 22.7%, opioids in 21.4%, hypnotics in 17.3%, and antibiotics in 14.6%. In four patients, multiple agents were determined. Skin prick test was positive in 35.1% and IDT positivity was found in 98.6%. Surgery was cancelled in 40% (n = 30), but it was determined that 50 patients (66.7%) underwent surgery after drug tests. All of them tolerated surgery.

CONCLUSıON

A large number of patients were evaluated because we are a reference hospital. The most common culprit drug group in POH is NMBA; reanesthesia situations are safe after allergist evaluation.

Insect Allergy: Barriers in Training and Practice-A Work Group Report of the AAAAI Anaphylaxis Committee

BACKGROUND

The evaluation and management of insect sting allergy is a complex core competency taught in Allergy and Immunology fellowship programs. It is unclear whether current training on insect allergy is sufficient to meet the needs of the field and what training barriers exist.

OBJECTIVE

To investigate the extent of training on stinging insect allergy and factors currently impacting stinging insect allergy clinical practice through a pilot needs-assessment survey.

METHODS

A Web-based questionnaire was designed and sent to a 20% random sample of American Academy of Allergy, Asthma & Immunology member categories. Data were analyzed for descriptive frequencies.

RESULTS

A total of 78 responses were received (11% response rate). Respondents' mean age was 53.7 years, 52% were female, and 92.3% were physicians. The mean time since training completion was 18.4 years. During fellowship training, 95.7% were educated on stinging insect allergy, 87.1% reported conducting testing, and 82.6% ordered venom immunotherapy (VIT). During training, 50% of respondents managed 1 to 5 patients with venom allergy (38% managed > 5, and 12% none). After fellowship, 97.3% reported evaluating patients with stinging insect allergy, 90.3% report evaluating 1 to 5 patients per month, and 93.2% and 87.5% offer testing and VIT, respectively. A patient's decision to not start VIT was the most common barrier reported by 81.8%.

CONCLUSIONS

In this pilot needs-assessment survey, the majority reported training and education on insect allergy during fellowship, although patient exposure was low for most. After fellowship, insect allergy evaluations increased up to 24-fold compared with fellowship training and patient-driven decisions are the most common deterrent for VIT.

Unraveling the Cause of Perioperative Anaphylaxis: The Role of Patent Blue Dye and Midazolam

We report a case of anaphylactic shock in a patient scheduled for a left mastectomy with sentinel lymph node biopsy who was found to be allergic to both midazolam and patent blue dye. This case underscores the occurrence of dual drug allergy in a single patient, with the possibility of synergistic effects that cannot be ruled out. Additionally, it emphasizes the vital role of the immunoallergology team in suspected anaphylaxis cases, as their specialized knowledge is crucial for establishing an accurate diagnosis and identifying the causative agents.

Cold-induced anaphylaxis: new insights into clinical and genetic characteristics

Introduction

The pathogenesis of cold urticaria (ColdU) and cold-induced anaphylaxis (ColdA) remains poorly understood, and ColdA is underrepresented in anaphylaxis literature. Laboratory features to guide management are largely unknown. This study evaluated basal serum tryptase (BST) and total immunoglobulin E (IgE) levels in ColdU and ColdA, their associations with clinical features, and the utility of testing for the KIT p.D816V variant in blood leukocytes and hereditary α-tryptasemia (HαT).

Methods

Ninety-two adults with ColdU were enrolled. ColdA was defined as a reaction involving skin and/or visible mucosal tissue with cardiovascular, respiratory, or gastrointestinal manifestations. Evaluations included patient history, standard cold stimulation testing (sCST) using an ice cube and TempTest®, and laboratory tests.

Results

ColdA was diagnosed in 35.9% of patients. ColdU phenotypes based on sCST included typical ColdU (52.2%), localized cold-reflex urticaria (5.4%), and ColdU with negative sCST (42.4%). Negative sCST, compared to typical ColdU, was associated with fewer ColdA cases (p = 0.004) but more spontaneous wheals (p < 0.001). ColdA patients more frequently exhibited generalized wheals (p = 0.047), skin angioedema (p = 0.007), oropharyngeal/laryngeal manifestations (p < 0.001), and itchy earlobes (p = 0.002) than non-ColdA patients. Elevated BST levels (>11.4 ng/mL) in 9.8% of patients were attributed to KIT p.D816V and/or HαT. KIT p.D816V was detected in 6.6% of ColdU and 6.3% of ColdA patients. HαT prevalence was higher in ColdU (10.9%) and ColdA (15.2%) than the general population (estimated at 5.7%; p = 0.041 and p = 0.038). Total IgE levels were significantly higher in ColdA than non-ColdA (p = 0.021).

Discussion

This study confirmed clinical features linked to ColdA previously identified by the multicenter COLD-CE study, including generalized wheals, skin angioedema, oropharyngeal/laryngeal manifestations, and itchy earlobes. We identified new high-risk features. ColdA is more frequently associated with typical ColdU than with ColdU with negative sCST, the latter being linked to spontaneous wheals. ColdA is additionally associated with higher total IgE levels. Furthermore, patients with ColdU and ColdA exhibit higher prevalence of KIT p.D816V and HαT compared to general population data, a finding not previously reported. Further research is needed to explore their clinical implications.

Biphasic anaphylaxis in a Canadian tertiary care centre: an evaluation of incidence and risk factors from electronic health records and telephone interviews

BACKGROUND

Our previous 2007 study reported a 19.4% rate of biphasic anaphylaxis in Kingston, Ontario. Since then, few updates have been published regarding the etiology and risk factors of biphasic anaphylaxis. This study aimed to describe the incidence of and predictors of biphasic anaphylaxis in a single centre through a retrospective evaluation of patients with diagnosed anaphylaxis.

METHODS

From November 2015 to August 2017, all patients who presented to the emergency department at two hospital sites in Kingston given a diagnosis of "allergic reaction," "anaphylaxis," "drug allergy," or "insect sting allergy," were evaluated. Patients were contacted sometime after ED discharge to obtain consent and confirm symptoms and timing of the reaction. A trained allergist determined if criteria for anaphylaxis were met and categorized the reactions as being uniphasic, biphasic, or non-anaphylactic biphasic. A full medical review of the event ensued, and each type of anaphylactic event was statistically compared.

RESULTS

Of 138 anaphylactic events identified, 15.94% were biphasic reactions, 79.0% were uniphasic, and 5.07% were classified alternatively as a non-anaphylactic biphasic reaction. The average time of a second reaction was 19.0 h in patients experiencing biphasic reactivity. For biphasic anaphylaxis, the symptom profiles of second reactions were significantly less severe (p = 0.0002) compared with the initial reaction but significantly more severe than non-anaphylactic biphasic events (p < 0.0001).No differences of management were identified between events.

CONCLUSION

The incidence of biphasic reactions in this cohort was 15.94% and the average second-phase onset was 19.0 h. In biphasic reactivity, it appears that the symptom profile second reaction is less severe compared to the first reaction.

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.

Cost-effectiveness of watchful waiting versus immediate emergency department transfer after epinephrine autoinjector use in Canada

BACKGROUND

Until recently, immediate emergency department (ED) transfer after food-related anaphylactic reactions was recommended regardless of symptom resolution following use of an epinephrine autoinjector (EAI). We evaluated the cost-effectiveness of delayed ED transfer after EAI use in non-medical settings (watchful waiting) compared to immediate ED transfer among pediatric patients with food allergies in Canada.

METHODS

We developed a probabilistic Markov model of individuals starting at age of one year who are at risk of severe food-related allergic reactions requiring epinephrine. We evaluated medical costs (in 2022 Canadian dollars) and quality-adjusted life years (QALY) of each strategy over a 20-year horizon. In the base case, we assumed a tenfold increase in food allergy fatality for patients under watchful waiting, which we increased to 100- to 1,000-fold in sensitivity analysis. The analysis was conducted from the Canadian healthcare system perspective with a 1.5% annual discount rate and a willingness-to-pay (WTP) threshold of $50,000 per QALY.

RESULTS

Immediate ED transfer following EAI use resulted in a decreased risk of food allergy fatality of 9.2 × 10- 5 over 20 years, which is equivalent to < 1 fatality per 200,000 patient-years. Watchful waiting resulted in cost savings of $1,157 per patient and a QALY loss of 7.28 × 10- 4; an incremental cost per QALY saved of $1,589,854. The incremental cost per death prevented with immediate ED transfer was $12,586,613. Watchful waiting remained cost-effective in all sensitivity and scenario analyses, except under extreme increases in fatality risk of 500-fold and 1,000-fold.

CONCLUSIONS

Watchful waiting for symptom re-occurrence following EAI administration in non-medical settings is cost-effective.

Copy Number Variation in Asthma: An Integrative Review

Asthma is a complex disease with varied clinical manifestations resulting from the interaction between environmental and genetic factors. While chronic airway inflammation and hyperresponsiveness are central features, the etiology of asthma is multifaceted, leading to a diversity of phenotypes and endotypes. Although most research into the genetics of asthma focused on the analysis of single nucleotide polymorphisms (SNPs), studies highlight the importance of structural variations, such as copy number variations (CNVs), in the inheritance of complex characteristics, but their role has not yet been fully elucidated in asthma. In this context, an integrative review was conducted to identify the genes and pathways involved, the location, size, and classes of CNVs, as well as their contribution to asthma risk, severity, control, and response to treatment. As a result of the review, 16 articles were analyzed, from different types of observational studies, such as case-control, cohort studies and genotyped-proband or trios design, that have been carried out in populations from different countries, ethnicities, and ages. Chromosomes 12 and 17 were the most studied in three publications each. CNVs located on 12 chromosomes were associated with asthma, the majority being found on chromosome 6p and 17q, of the deletion type, encompassing 30 different coding-protein genes and one pseudogene region. Six genes with CNVs were identified as significant expression quantitative locus (eQTLs) with mean expression in asthma-related tissues, such as the lung and whole blood. The phenotypic variability of asthma may hinder the clinical application of these findings, but the research shows the importance of investigating these genetic variations as possible biomarkers in asthma patients.

Stinging Ant Anaphylaxis: Advances in Diagnosis and Treatment

Stinging ants represent a wide range of over 200 different species across the world, of which Solenopsis, Myrmecia, Pogonomyrmex, and Brachyponera genera account for a substantial economic and healthcare burden. S. invicta (red imported fire ant [IFA]) and M. pilosula (jack jumper ant [JJA]) are 2 species of high clinical importance, known to cause anaphylaxis in humans, with numerous reported fatalities. Diagnostic testing should be performed in patients with a history of a systemic reaction with skin testing and/or in vitro specific immunoglobulin E (IgE) testing. In vitro testing is commercially available for IFA through whole-body extract specific IgE and JJA venom-specific IgE, but not widely available for other stinging ant species. Commercial venom component testing for IFA and JJA is currently not available. Patients with a clinical history and positive specific IgE testing should undergo treatment with specific immunotherapy, which is currently available for IFA and JJA. Buildup may be performed using conventional, semi-rush, rush, or ultra-rush schedules with similar risk profiles for IFA. Optimal duration for whole=body extract immunotherapy for IFA and specific JJA venom immunotherapy is not well studied, but generally recommended for at least 3 to 5 years. Sting challenges are used in research settings, primarily to assess treatment efficacy of immunotherapy.

Evaluation of allergic diseases in children diagnosed with cutaneous mastocytosis

Background: Cutaneous mastocytosis (CM) is the most common type of mastocytosis in children. The atopy frequency in these patients is typically similar to that in the general population, but a higher incidence of anaphylaxis is reported. Objective: This study aimed to evaluate the presence of allergic diseases in children diagnosed with CM and its impact on clinical manifestations. Methods: Children diagnosed with CM at Ankara Bilkent City Hospital Pediatric Allergy and Immunology Clinic between September 2019 and September 2023 were included in the study. Data, including demographic information, clinical details, and laboratory results, were gathered from medical records, encompassing personal and family allergy history. Results: The study included 58 patients (median [interquartile range{IQR}] age, 64 months [29-100.5 months]; 69% boys) with skin lesions as the primary concern. The median (IQR) age at which the lesions appeared was 9 months (3-39.25 months), and the median (IQR) age at hospital admission was 12 months (5- 50 months). The median (IQR) age at CM diagnosis was 13 months (6-53.5 months). The median (IQR) baseline tryptase value was 5.45 μg/L (3.93-9.00 μg/L), and 16 had an elevated tryptase value (>8 μg/L). Allergic diseases were present in 39.65% of the patients, with atopic dermatitis (18.9%) being the most common, followed by asthma (10.3%), allergic rhinitis (5.2%), food allergy (1.7%), and drug and bee venom allergies (1.7%). One patient had a history of anaphylaxis, diagnosed 4 months after consuming yogurt. A total of 18 patients, including this patient, were prescribed an adrenaline autoinjector. Conclusion: Various allergic diseases occurred in ∼40% of patients with CM and most commonly manifest as atopic dermatitis; 31% patients with risk factors for anaphylaxis were prescribed an adrenaline autoinjector.

Shared Decision-Making in Insect Sting Allergy: To Bee or Not to Bee?

Evaluation and management of insect sting allergy are often not straightforward when there is uncertainty about the history of reaction, the significance of test results, and the risk of severe reaction to future stings. Patients encounter misinformation about the chance of reaction and may have strong beliefs about the need for treatment. Shared decision-making encourages the clinician to listen to the patients' concerns and beliefs, share relevant information and evidence, and partner with patients to incorporate their values and preferences. This review discusses some major decision points in diagnosis and treatment of insect-allergic patients, with attention to the potential burdens or harms that are important to patients and factors that relate to patients' values and preferences concerning the choices they must make. This is especially true in patients with no history of moderate to severe sting anaphylaxis in whom the risk may be overestimated, but it can also be important in patients who underestimate the risk associated with severe sting anaphylaxis. Clinicians should become more knowledgeable about patient-important beliefs and outcomes and engage in shared decision-making to help patients understand and be comfortable with the choices they must make.

Mast Cell Disorders and Hymenoptera Venom-Triggered Anaphylaxis: Evaluation and Management

Patients with Hymenoptera venom allergy (HVA), especially those with severe anaphylaxis, frequently have concomitant clonal mast cell disease (MCD) in the form of systemic mastocytosis or monoclonal mast cell activation syndrome. Detection of clonal MCD is important because it will have significant consequences for managing HVA. Therefore, we recommend patients with HVA be systematically screened for clonal MCD. The pretest probability of clonal MCD can be assessed in a stepwise fashion starting with examination of the skin for typical monomorphic maculopapular cutaneous mastocytosis lesions; measurement of the baseline serum tryptase (BST) and tryptase genotyping for patients with BST greater than 11 ng/mL; followed by the Red Española de Mastocitosis score, which is calculated using anaphylaxis clinical features, BST, and the patient's sex. A bone marrow biopsy should be performed in patients with monomorphic maculopapular cutaneous mastocytosis, a Red Española de Mastocitosis score of 2 or greater, or an elevated BST based on tryptase genotype. Patients with HVA and a clonal MCD should be treated with immunotherapy directed against the Hymenoptera venom for which they are sensitized. For this high-risk subgroup of patients with HVA, it is recommended to continue immunotherapy for more than 5 years or indefinitely and to carry at least three epinephrine autoinjectors. Future studies should determine whether KIT D816V-selective tyrosine kinase inhibitors are effective at preventing or reducing the severity of Hymenoptera-venom triggered anaphylaxis in patients with clonal MCD.

Towards a common approach for managing food allergy and serious allergic reactions (anaphylaxis) at school. GA2LEN and EFA consensus statement

GA2LEN and EFA propose minimum specifications for all industrialised countries/regions to work towards to support students with food allergies in educational settings. We reviewed research and legislation and gained feedback from over 100 patient and professional groups. We built shared expectations around: 1. training all school staff about what food allergy is, the symptoms of allergic reactions, what to do in an emergency, and when and how to use and store devices that laypeople can use to administer adrenaline (epinephrine). 2. preventing allergic reactions by using clear labelling on school menus and prepacked and non-prepacked foods and regular cleaning where students eat. 3. preparing for serious allergic reactions, with written emergency action plans for every student with food allergies, legislation allowing schools to store adrenaline for anyone who needs it in an emergency (not just those prescribed it), and training and legal safeguards for staff administering adrenaline. 4. including affected students by discussing food allergy in the curriculum, raising awareness among all students and caregivers and reviewing school processes regularly. It is time for national and international action at the policy level. Patient groups, education networks and professional societies all play a role in campaigning for shared next steps.

Perioperative anaphylaxis manifesting as cardiac arrest during cardiac surgery

Perioperative anaphylaxis is a serious entity with high morbidity and mortality. Perioperative anaphylaxis can be caused by any of the multitude of medications and substances used in anesthesia and surgery, and the most common causes include neuromuscular blocking agents, antibiotics, antiseptics, latex, and dyes. The differential diagnosis of perioperative anaphylaxis is wide from both an immunologic and a nonimmunologic standpoint. The majority of the intraoperative anaphylaxis reactions are thought to be immunoglobulin E (IgE) mediated; however, other primary non-IgE-mediated mechanisms can also be present. Clinical manifestations can vary from mild cutaneous exanthema to cardiac arrest. Tryptase can be helpful in identifying perioperative anaphylaxis. In this article, we present the case of a 75-year-old man who had a cardiac arrest without skin symptoms perioperatively during coronary artery bypass surgery. We describe the presentation, strategic evaluation, and subsequent management with recommendations for future surgery based on his evaluation and the identified culprit. Subsequent surgery was later completed. Understanding the clinical presentation, key components of testing, and recommendations for future management of perioperative anaphylaxis are invaluable skills that the allergist can provide for the patient and the anesthesia and surgery teams.

Biomarkers for the Molecular Diagnosis of IgE-Mediated Hymenoptera Venom Allergy in Clinical Practice

Hymenoptera venom allergy (HVA) is a potentially life-threatening condition, making accurate diagnosis crucial for identifying significant IgE sensitizations and enabling effective venom immunotherapy. In this review, we provide a detailed overview of biomarkers for the molecular diagnosis of IgE-mediated hypersensitivity to Hymenoptera insect venoms in clinical practice, and we present, in a structured manner, their importance in differentiating genuine sensitizations versus cross-sensitizations using different diagnostic procedures. Updated algorithms are provided, along with the advantages and limitations of molecular diagnosis approaches. Geographical variations and rare species may pose further challenges in diagnosing and treating HVA, adding complexity to HVA management. This review informs readers about performing tailored diagnostics based on molecular allergen biomarkers and subsequent treatment strategies.

Allergen immunotherapy

Allergen immunotherapy (AIT) is a potentially disease-modifying therapy that is effective for the treatment of allergic rhinitis/conjunctivitis, allergic asthma and stinging insect hypersensitivity. The decision to proceed with AIT should be made on a case-by-case basis, based on a comprehensive evaluation of the patient, allergy testing and a thorough discussion with the patient about treatment goals, risks vs. benefits, and long-term commitment to the treatment plan. For those with allergic rhinitis and/or asthma, it is also important to consider individual patient factors, such as the degree to which symptoms can be reduced by avoidance measures and pharmacological therapy, the amount and type of medication required to control symptoms, the adverse effects of pharmacological treatment, and patient preferences.Since AIT is associated with a risk of anaphylaxis, it should only be prescribed by physicians who are adequately trained in the treatment of allergic conditions. Furthermore, for subcutaneous therapy, injections must be given under medical supervision in clinics that are equipped to manage anaphylaxis. In this article, we review the indications and contraindications, patient selection criteria, and details regarding the administration, safety and efficacy of AIT for allergens other than foods. Immunotherapy for food allergy will be discussed in the Oral Immunotherapy article in this supplement.

National trends in the prevalence and recurrence of anaphylaxis across all ages: The role of neighborhood deprivation and comorbidity (2002-2019)

Background

Understanding the trends of anaphylaxis and risk factors associated with its recurrence is essential for the effective management and prevention of this condition.

Objective

This study aimed to analyze the prevalence trends of anaphylaxis and identify risk factors for recurrence, with a focus on the influence of neighborhood deprivation and comorbidities, across all age groups.

Methods

We conducted a retrospective administrative cohort study on anaphylaxis utilizing the National Health Insurance-National Sample Cohort (NHIS-NSC) database in Korea (2002-2019). Anaphylaxis was defined with ICD-10 codes for the diagnosis combined with prescription codes. The Neighborhood Deprivation Index was used to identify the risk of recurrent anaphylaxis. Trends in the annual prevalence and recurrence of anaphylaxis were assessed through joinpoint regression and Cox proportional hazard models.

Results

Out of the 1,137,861 individuals studied, 37,012 (3.25%) cases of anaphylaxis were identified. Among these, 5783 individuals (15.6%) experienced a recurrence, half of them experiencing it within the first year after the initial episode. The highest incidence of anaphylaxis was observed in children and adolescents, followed by middle-aged adults. A rapid increase in anaphylaxis cases was observed from 2002 to 2006 (Annual Percentage Change [APC], 33.2), followed by a more gradual increase until 2013 (APC, 12.8), and a stable trend from 2013 to 2019 (APC, 0.61). Males and adult age groups exhibited an increased risk of recurrence. Living in an area with neighborhood deprivation and the presence of comorbid conditions were associated with increased recurrence risk.

Conclusions

The increasing prevalence of anaphylaxis and its association with certain risk factors calls for targeted intervention. Addressing neighborhood deprivation and comorbid conditions may aid in reducing the recurrence and overall burden of anaphylaxis.

An International Delphi Consensus on the Management of Pollen-Food Allergy Syndrome: A Work Group Report of the AAAAI Adverse Reactions to Foods Committee

BACKGROUND

Pollen-food allergy syndrome (PFAS) is common among patients with allergic rhinitis. Treatment recommendations for patients with PFAS remain variable.

OBJECTIVE

To develop consensus recommendation statements for managing patients with PFAS.

METHODS

An international panel of allergists, researchers, and nutritionists with an interest in PFAS from 25 different institutions across 11 countries convened and a list of statements was written by 3 authors. The RAND/University of California Los Angeles methodology was adopted to establish consensus on the statements.

RESULTS

After 2 Delphi rounds, a consensus was reached on 14 statements. The panel agreed that patients with PFAS would benefit from counseling on the nature and basis of PFAS and the rare chance of more severe systemic reactions and their recognition. The panel agreed on avoiding the raw food responsible for the index reaction, but not potentially cross-reactive fruits/vegetables based on the responsible food of the index reaction. Epinephrine autoinjectors should be recommended for patients with PFAS who experienced severe symptoms (beyond the oropharynx) or for patients considered at risk for severe reactions. The panel agreed that the benefit of allergen immunotherapy remains unclear and that PFAS should not be considered the primary indication for such intervention.

CONCLUSIONS

We developed consensus statements regarding counselling patients about the nature and severity of PFAS, potential risk factors, dietary avoidance, epinephrine autoinjector prescription, and allergen immunotherapy consideration for patients with PFAS.

Pharmacokinetic and Pharmacodynamic Profile of Epinephrine Nasal Spray Versus Intramuscular Epinephrine Autoinjector in Healthy Adults

BACKGROUND

Standard of care for anaphylaxis treatment is intramuscular (IM) epinephrine. An epinephrine nasal spray (ENS) is under development as an alternative form of administration.

OBJECTIVE

To compare the pharmacokinetic and pharmacodynamic (PD) profile of 13.2 mg ENS with 0.3 mg IM epinephrine autoinjector.

METHODS

Data from 4 open-label phase 1 crossover studies conducted in healthy adults were pooled to determine the pharmacokinetic and PD profile of a single 13.2 mg ENS dose delivered by 2 consecutive sprays of 6.6 mg each in opposite (n = 224 doses) or the same nostril (n = 75 doses) compared with the 0.3 mg IM autoinjector (n = 215 doses). Each participant served as their own control. Blood samples and vital signs were collected predose and at multiple intervals from 0 to 360 minutes postdose.

RESULTS

ENS rapidly increased the plasma epinephrine concentration, with levels that were overall greater than IM autoinjector. Median (range) time to maximum plasma epinephrine concentration with ENS opposite nostrils, ENS same nostril, and IM autoinjector was 25.1 (1.3-362.1), 20.1 (3.0-120.2), and 20.0 (1.0-121.3) minutes, respectively. The area under the plasma concentration-time curve for 0 to 360 minutes was significantly higher with ENS than with the IM autoinjector (geometric mean ratio [90% CI], 155% [140%-172%] with ENS opposite nostrils, 159% [138%-182%] with ENS same nostril). The PD effects on heart rate and blood pressure were similar in pattern and magnitude among all 3 treatment groups.

CONCLUSIONS

ENS rapidly achieved plasma epinephrine levels greater and more sustained than the IM autoinjector and with a similar PD effect.

Intramuscular versus intravenous epinephrine administration in a pediatric porcine model of cardiopulmonary resuscitation

Background

American Heart Association Pediatric Life Support guidelines recommend epinephrine administration via intravenous (IV) or intraosseous (IO) route, with endotracheal (ET) administration admissible in the absence of IV/IO access. Establishing IV/IO/ET access can take several minutes and may require proficient skills and/or specific equipment, which may not be readily available in all situations. Alternatively, intramuscular (IM) epinephrine could be administered immediately. At present, there is limited data on the use of IM epinephrine in pediatric resuscitation.

Aim

To compare IM with IV epinephrine in a pediatric porcine model of asphyxia-induced cardiac arrest. We hypothesized that in a pediatric animal model of cardiac arrest, IM epinephrine would result in a similar time to achieve return of spontaneous circulation (ROSC) to IV epinephrine.

Methods

Twenty pediatric piglets (5-10 days old) were anesthetized and asphyxiated by clamping the endotracheal tube. Piglets were randomized to IM or IV epinephrine with bradycardic or asystolic cardiac arrest (n = 5/group) and were resuscitated. Time to ROSC was recorded; blood plasma was collected throughout resuscitation for measurement of epinephrine concentration; heart rate, arterial blood pressure, carotid blood flow, cardiac function, and cerebral oxygenation were continuously recorded throughout the experiment.

Results

Time to ROSC and the number of piglets that achieved ROSC were comparable between IM and IV epinephrine groups with either bradycardic or asystolic cardiac arrest.

Conclusions

In a pediatric piglet model of bradycardic and asystolic cardiac arrest, administration of IM epinephrine resulted in similar resuscitative outcomes to IV epinephrine. Although immediate IM epinephrine injection may provide a first-line treatment option until subsequent IV/IO access is established, large, randomized trials are needed to confirm our finding before it can be used during pediatric resuscitation.

Non-IgE-mediated drug-induced hypersensitivity reactions in pediatrics

PURPOSE OF REVIEW

Despite their prevalence and potential severity, non-IgE-mediated drug-induced hypersensitivity reactions (DHRs) are under-researched and poorly defined, particularly in children. Presentations range from mild cutaneous reactions to severe systemic diseases, with pathophysiological mechanisms and reliable diagnostic markers not well established. The lack of validated tests often leads to permanent drug restrictions, reliance on second-line drugs, and increased costs. Focusing on recent advancements and areas needing further research, this review aims to enhance children's recognition, diagnosis, and management of non-IgE-mediated DHRs.

RECENT FINDINGS

Recent studies have enhanced the understanding of immediate and delayed non-IgE-mediated drug reactions. Key findings include the Mas-related G protein-coupled receptor X2 in mast cells and the identification of HLA alleles linked to severe cutaneous adverse reactions, such as Stevens-Johnson syndrome and toxic epidermal necrolysis. Improved diagnostic techniques, including skin testing, show promise in identifying immediate and delayed non-IgE DHRs. Additionally, research highlights the impact of cofactors, drug metabolites, and co-infections on these DHRs and explores potential biomarkers for predicting reaction severity.

SUMMARY

Non-IgE-mediated DHRs are a significant cause of morbidity and treatment changes in pediatric patients. Recent research underscores their clinical presentations and mechanisms, paving the way for more precise diagnostic and therapeutic strategies to improve patient outcomes.

Toxicological consequences of yellowjacket wasp and its larvae entomophagy in Himalayan region of Nepal; case report and review of literature

Entomophagy, or insect consumption, is a common traditional practice in Asia, Africa, and South America including Nepal. Despite its longstanding cultural presence, there is limited literature on the toxicological effects of ingesting wasp larvae. This case report describes seven individuals who experienced toxicity after consuming pan-fried yellowjacket wasp larvae in August 2023. Symptoms included seizures, nausea, dizziness, blurred vision, and cardiovascular instability. The cases varied in severity, with some patients exhibiting profound hypotension and neurological symptoms. The symptoms suggest possible neurotoxic effects of venom components in wasp larvae, though some studies indicate larvae may lack venom glands. The slow progression and severity of symptoms highlight the need for further investigation into the toxicological profile of wasp larvae. Future research should focus on identifying specific venom components of yellowjackets, examining cooking impacts on toxicity, and exploring venom variations across wasp species to improve treatment approaches and safety protocols.

Epidemiology, Risk Factors, and Management of Biphasic Anaphylaxis

PURPOSE OF REVIEW

Biphasic anaphylaxis is a variant of anaphylaxis characterized by recurrence of symptoms after initial resolution of anaphylaxis. It was first described in the mid 1990s by Popa and Lerner. Our understanding of the pathophysiology and epidemiology of the condition has advanced considerably since then. The purpose of this manuscript is to review the literature surrounding biphasic anaphylaxis while highlighting key works and recent advances.

RECENT FINDINGS

Prior studies have estimated biphasic anaphylaxis occurs in 0.4-20% of anaphylaxis episodes. The wide range may be related to differences in anaphylaxis diagnostic criteria which was inconsistent across studies. Recently identified risk factors for occurrence of biphasic anaphylaxis include severe initial symptoms including hypotension or hypoxia, delay in epinephrine use, and greater than one dose of epinephrine required to treat symptoms. Despite our progress to better understand biphasic anaphylaxis, there remain gaps in the literature. This article aims to review the recent literature including, epidemiology, risk factors, and management of biphasic anaphylaxis.

10 practical priorities to prevent and manage serious allergic reactions: GA2LEN ANACare and EFA Anaphylaxis Manifesto

This Anaphylaxis Manifesto calls on communities to prioritise 10 practical actions to improve the lives of people at risk of serious allergic reactions. The Global Allergy and Asthma European Network and the European Federation of Allergy and Airways Diseases Patients' Associations (EFA) compiled patient-centric priorities. We used qualitative consensus methods, research evidence and feedback from over 200 patient groups, stakeholder organisations and healthcare professionals. We encourage healthcare, education and food organisations to collaborate with people at risk of serious allergic reactions to tackle safety, anxiety and financial burdens for individuals and societies. Key priorities for prevention include awareness-raising campaigns for the public and professionals, school and workplace initiatives and mandatory precautionary allergen labels on food. Priorities for improving immediate and long-term management include educating healthcare professionals, patients and schools about when and how to use adrenaline, funding two approved adrenaline devices for everyone at risk, and facilitating access to allergy specialists. Integrated care pathways should include clinical and non-clinical management options such as individualised risk assessment and quality of life assessment, self-management plans, dietetic and psychosocial support and peer support. Organisations around the world are committing to work together towards these priorities.

Infusion Reactions to Infliximab in Pediatric Patients with Inflammatory Bowel Disease

Infliximab (IFX) is a recombinant DNA-derived chimeric IgG monoclonal antibody protein that inhibits tumor necrosis factor alpha (TNF-α). IFX, like other agents derived from foreign proteins, can cause infusion reactions both during and after the infusion. The incidence of infusion reactions ranges between 0% and 15% in pediatric patients. The potential underlying mechanisms for these reactions may include anaphylaxis and anaphylactoid reactions, cytokine release syndrome, serum sickness-like reactions, and the development of antibodies against IFX. Several precautions can help reduce the risk of a new infusion reaction, such as a gradual increase in the infusion rate, scheduled infusions, and administering premedication or immunomodulators alongside IFX. Acute mild to moderate reactions often resolve spontaneously after a temporary cessation of the infusion or reduction in the infusion rate. Strategies like graded dose challenges and premedication can be utilized to prevent recurrence. In cases of severe reactions, desensitization or switching to an alternative biologic may be considered. This article aims to review the most recent guidelines for managing IFX-related infusion reactions in pediatric patients with inflammatory bowel disease (IBD), relying on the best available evidence.