Stinging insect hypersensitivity: A practice parameter update 2016

The role of the environment in allergic skin disease

PURPOSE OF REVIEW

This paper explores how environmental factors influence allergic skin diseases, including atopic dermatitis (AD), contact dermatitis (CD), urticaria, angioedema, and reactions to drugs and insect bites.

RECENT FINDINGS

Research indicates a significant impact of environmental elements on allergic skin diseases. High air pollution levels exacerbate symptoms, while climate change contributes to increased skin barrier dysfunction, particularly affecting AD. Allergen prevalence is influenced by climate and pollution. Irritants, like those in detergents and cosmetics, play a major role in CD. Plants also contribute, causing various skin reactions. Understanding the interplay between environmental factors and allergic skin diseases is crucial for effective management. Physicians must address these factors to support patient well-being and promote skin health amidst environmental changes.

Military accession guidelines: An allergy focus

Medical evaluation for military applicants is an intricate process that requires an understanding of the terminology, standards, and guidelines. Allergy providers are often called to provide medical evaluations for patients who desire to join the military services. Without understanding the complexities and nuances of military medical evaluations, a provider may delay or not be able to assist their patient in obtaining the desired goal of joining the services. This article reviews the terminology of military medical evaluations and the guidelines and processes for these evaluations. We also focus our discussion on common allergic conditions that may be disqualifying for service and provide expert opinions of the subtleties of these conditions to provide the allergist with a practical approach to medical evaluations. Finally, we provide a list of resources that are accessible to any provider engaged in military medical evaluations for accessions.

High burden of clonal mast cell disorders and hereditary α-tryptasemia in patients who need Hymenoptera venom immunotherapy

BACKGROUND

In patients who require venom immunotherapy (VIT), there is a need to identify underlying mast cell (MC) disorders since these may affect the risk and severity of future sting reactions and the long-term effectiveness of VIT.

METHODS

1319 individuals with Hymenoptera venom allergy (HVA) who needed VIT from referral centers in Slovenia, Austria, Croatia, and Poland underwent examination for KIT p.D816V in peripheral blood leukocytes (PBL) using a highly sensitive PCR test and tryptase genotyping by digital droplet PCR. We also included 183 control individuals with large local reactions (LLRs) to Hymenoptera stings and with asymptomatic sensitization to Hymenoptera venoms.

RESULTS

285 of 1319 individuals recommended for VIT (21.6%) were positive for KIT p.D816V in PBL, preferably those who present with severe reaction (33.9% [n = 207 of 610] with Ring-Messmer grade 3-4 vs. 11% [n = 78 of 709] with Grade 1-2; p < .0001), whereas only 1.3% (n = 2 of 152) of controls with LLR and none with asymptomatic sensitization (n = 31) had KIT p.D816V. KIT p.D816V allelic burden was higher in those with severe reaction (median 0.018% [n = 207] in Grade 3-4 vs. 0.001% [n = 78] in Grade 1-2; p < .0001), and the majority had normal baseline serum tryptase levels (69% [n = 196 of 285]). All KIT p.D816V-positive individuals (n = 41) who underwent bone marrow (BM) biopsy were found to have underlying clonal diseases, principally BM mastocytosis. HαT was also associated with severe HVA and symptoms (p < .01), and remarkably, 31.0% (n = 31 of 100) were found to have concomitant KIT p.D816V. Concomitant HαT and KIT p.D816V showed an additive effect, and having both was associated with the highest risk for severe HVA, even higher than having either HαT or KIT p.D816V alone (OR = 3.8; p < .01).

CONCLUSIONS

By employing prospective universal tryptase genotyping and examination for KIT p.D816V in PBL in large HVA populations, we have demonstrated a high burden of clonal MC disorders and HαT in patients who require VIT.

Hymenoptera Venom Immunotherapy Meets Factitious Disorder

Factitious disorder on self is a psychiatric disorder in which individuals fabricate or induce signs or symptoms of a disease. Factitious anaphylaxis, with symptoms suggestive of a life-threatening allergic reaction, is extremely rare. Several cases of factitious disorder reactions during allergen immunotherapy for airborne allergens have been reported. We report the case of a young female patient who presented factitious anaphylaxis during venom immunotherapy to vespid venom extract. Symptoms of stridor, dyspnea, coughing and loss of consciousness were observed during the built-up phase of venom immunotherapy, mimicking allergic reactions to the venom extracts. Diagnosis of factitious disorder prompted the discontinuation of venom immunotherapy.

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.

Imported fire ant immunotherapy

Imported fire ants (IFAs) permeate many areas of the United States. The IFA allergy is a significant health problem for children and adults. Stings from IFAs cause pustules, localized reactions, and anaphylaxis. There have been at least 32 deaths attributed to IFA stings. Because of the difficulty with the extraction of venom from the fire ants, whole body extracts are the only commercially available serum for immunotherapy. Fortunately, whole body extract immunotherapy given conventionally or through the rush method has proven to be efficacious and safe. It is recommended for the treatment of IFA hypersensitivity. Maintenance immunotherapy is typically given at 4-week intervals. However, more recent research has revealed that these intervals can gradually be extended up to 12 weeks similar to flying Hymenoptera venom immunotherapy. Long-term adherence to IFA immunotherapy remains an obstacle for many patients despite its potential as a life-saving treatment.

Challenges in Drug and Hymenoptera Venom Hypersensitivity Diagnosis and Management in Mastocytosis

Mastocytosis is a myeloproliferative neoplasm characterized by abnormal proliferation and activation of clonal mast cells typically bearing the KITD816V mutation. Symptoms manifest due to the release of bioactive mediators and the tissue infiltration by neoplastic mast cells. Mast cell activation symptoms include flushing, pruritus, urticaria, abdominal cramping, diarrhea, wheezing, neuropsychiatric symptoms, and anaphylaxis. Up to 50% of patients with mastocytosis report a history of provoked and unprovoked anaphylaxis, with Hymenoptera venom and drugs the most common culprits. NSAIDs, antibiotics, vaccines, perioperative medications, and radiocontrast media are often empirically avoided without evidence of reactions, depriving patients of needed medications and placing them at risk for unfavorable outcomes. The purpose of this review is to highlight the most common agents responsible for adverse drug reactions in patients with mastocytosis, with a review of current epidemiology, diagnosis, and management of drug hypersensitivity and Hymenoptera venom allergy.

Health disparities in hymenoptera venom allergy management

Background: Hymenoptera venom anaphylaxis (HVA) is reported in up to 3% of stings and accounts for approximately 40 US deaths annually. HVA patients require immediate availability of epinephrine and Allergist referrals for consideration of venom immunotherapy. Data regarding epinephrine autoinjector prescriptions, Allergist referral rates, and potential racial disparities are limited. Objective: The primary objective was to determine if there were statistically significant differences in epinephrine autoinjector prescriptions and Allergist referrals between white and African American patients. The secondary objectives were to determine if there were statistically significant differences between adult and pediatric patients and to determine if there were significant differences between epinephrine prescriptions between patients with and without Allergist referrals. Method: This study is a retrospective, descriptive chart review analyzing patients seen between January 01, 2019 and December 31, 2021. Data were obtained utilizing the Epic Systems (Verona, WI) application Slicer Dicer. Individual chart review was performed for age, race, epinephrine autoinjector prescription, and Allergist referral. Results: 342 patients were identified as having HVA. White patients (60 out of 219; 27.4%) were more likely to get epinephrine autoinjector prescriptions than African American patients (17 out of 109; 15.6%) (p = 0.018). Adult patients (25 out of 314; 8.0%) were less likely than pediatric patients (8 out of 28; 28.6%) to have Allergist referrals (p = 0.004). Patients with Allergist referrals (25 out of 32; 78.1%) were more likely to be prescribed an epinephrine autoinjector than patient without Allergist referrals (54 out of 310; 17.4%) (p < 0.00001). Conclusion: Epinephrine autoinjector prescriptions and Allergist referrals are low overall in HVA. Racial disparities were identified with African American patients being significantly less likely to receive epinephrine autoinjector prescriptions. Additionally, adult patients, who may be at increased risk, were less likely to receive Allergist referrals.

Potential and limitations of epitope mapping and molecular targeting in Hymenoptera venom allergy

Hymenoptera venom (HV) allergy can lead to life threatening conditions by specific IgE (sIgE)-mediated anaphylactic reactions. The knowledge about major allergens from venom of different clinically relevant species increased in the last decades, allowing the development of component-resolved diagnostics in which sIgE to single allergens is analysed. Despite these advances, the precise regions of the allergens that bind to IgE are only known for few HV allergens. The detailed characterization of IgE epitopes may provide valuable information to improve immunodiagnostic tests and to develop new therapeutic strategies using allergen-derived peptides or other targeted approaches. Epitope-resolved analysis is challenging, since the identification of conformational epitopes present in many allergens demands complex technologies for molecular analyses. Furthermore, functional analysis of the epitopeś interaction with their respective ligands is needed to distinguish epitopes that can activate the allergic immune response, from those that are recognized by irrelevant antibodies or T cell receptors from non-effector cells. In this review, we focus on the use of mapping and molecular targeting approaches for characterization of the epitopes of the major venom allergens of clinically relevant Hymenoptera species. The screening of the most relevant allergen peptides by epitope mapping could be helpful for the development of molecules that target major and immunodominant epitopes blocking the allergen induced cellular reactions as novel approach for the treatment of HV allergy.

Mosquito allergy: Immunological aspects and clinical management

Mosquito allergy has been conceived as the cutaneous reactions that appears during and after mosquito biting process; a perception that is supported by several scientific research. Additional data have led to conceive that other manifestations of allergic responses may occur as a cause of the exposure to somatic mosquito allergens. Two main phenotypes of mosquito allergy are identifiable: the cutaneous allergic reactions, induced by salivary allergens, and other manifestations of the allergic responses such as asthma and allergic rhino conjunctivitis that are caused by somatic allergens. The cutaneous reactions have kept the focus of attention of the scientific community. It appears as skin lesions that resembles the phenotype of papular urticaria with a defined natural history of the disease. Although these two phenotypes of mosquito allergy seem to be well differentiated in terms of the allergens that are involved and the routes of exposures, other factors such as geographical distribution, may participate. Mosquitoes have adapted to the host immune response against bites, producing immunomodulatory molecules that counteract such defensive response. The role that the immunomodulatory molecules have on the allergic immune response has not been studied yet and it is still not known if affects all mosquito allergy phenotypes. Only a few studies of allergen specific immunotherapy for cutaneous allergic reactions induced by mosquito bites have been done, and none for respiratory allergic responses. The clinical practice focuses on symptom management and avoiding mosquito bites as much as possible. Avoiding mosquitoes, using different well described methods, is still the best option to limit contact with these insects. The lack of knowledge of mosquito allergy have raised several questions that affects the clinical management of this allergic disease, from its diagnosis, prevention and immunotherapy.

KAAACI Guidelines for Allergen Immunotherapy

Allergen immunotherapy (AIT) is a causative treatment for various allergic diseases such as allergic rhinitis, allergic asthma, and bee venom allergy that induces tolerance to offending allergens. The need for uniform practice guidelines in AIT is continuously growing because of the increasing discovery of potential candidates for AIT and evolving interest in new therapeutic approaches. This guideline is an updated version of the Korean Academy of Asthma Allergy and Clinical Immunology recommendations for AIT published in 2010. This updated guideline proposes an expert opinion by allergy, pediatrics, and otorhinolaryngology specialists with an extensive literature review. The guideline deals with basic knowledge and methodological aspects of AIT, including mechanisms, clinical efficacy, patient selection, allergens extract selection, schedule and doses, management of adverse reactions, efficacy measurements, and special consideration in pediatrics. The guidelines for sublingual immunotherapy will be covered in detail in a separate article.

Fire ant Immunotherapy with inteRvals Extended to 12 weekS: The FIRES study

BACKGROUND

There are no studies describing 12-week extended maintenance interval (EMI) immunotherapy (IT) efficacy in preventing anaphylaxis to imported fire ant (IFA) stings.

OBJECTIVE

The purpose of this study was to determine the safety and efficacy of 12-week maintenance intervals in patients treated with IFA IT.

METHODS

After a minimum of 3 months of conventional maintenance interval IT and verification of baseline efficacy, adults with IFA hypersensitivity were prospectively enrolled and extended their maintenance doses to 6-, 8-, and 12-week intervals. Efficacy was confirmed by means of an annual IFA sting challenge.

RESULTS

A total of 25 patients initiated EMI. The severity of their initial systemic reactions was mild in 8 patients (32%), moderate in 10 patients (40%), and severe in 7 patients (28%). Maintenance IT duration at trial entry was less than 3 years in 18 patients (mean 11 months; range 3-28 months), 3 to 5 years in 4 patients (mean 46 months; range 36-57 months), and greater than 5 years in 5 patients (mean 111 months; range 67-197 months). The treatment cohort did not experience systemic reactions to extended interval injections, cluster refill injections, field stings, or sting challenges.

CONCLUSION

This prospective longitudinal cohort study revealed that in adults 18 years old or older who have received at least 3 months of maintenance dose IFA-whole body extract IT with proven efficacy, extension to a 12-week EMI is a safe effective treatment option. The benefits of EMI include a reduced number of injections, clinic visits, and lapses in maintenance IT.

The Value of Current Laboratory Tests in Diagnosing Food, Venom, and Drug Allergies

An accurate diagnosis of IgE-mediated allergies is necessary to inform risk management for severe allergic reactions including anaphylaxis for food, venom, and drug allergies. The most widely available laboratory test for allergy is serum-specific IgE testing, which is routinely used for food allergy and insect sting allergy. Testing for specific IgE is limited by high sensitivity and low specificity, resulting in concern regarding overdiagnosis. Testing of allergen components has led to improved diagnosis for some food and venom allergens. Additional options for laboratory tests, such as epitope analysis, basophil activation, and mast cell activation, are being investigated for their potential to optimize diagnosis and provide predictors for reaction severity and treatment response. In contrast, laboratory testing for drug allergy is more limited because to date, there are no well-validated commercial assays in the United States. Furthermore, it is important to diagnose delayed reactions to medications, because these also significantly affect decision-making regarding therapeutic options for infectious disorders. Reliable tests for both immediate and delayed drug hypersensitivity are much needed, because drug allergy labels can significantly limit treatment options for patients. Research in this area is emerging.

Venom Anaphylaxis: Decision Points for a More Aggressive Workup

Diagnostic testing of patients who present for evaluation of insect venom allergy can involve many levels of investigation. A detailed initial history is critical for diagnosis and prognosis. The severity of previous sting reactions and the presence or absence of urticaria or hypotension predict severe future sting reactions and underlying mast cell disorders. Venom skin tests and specific IgE measurement can confirm the diagnosis but have limited positive predictive value for the frequency and severity of future sting reactions. Testing for serum IgE to recombinant venom component allergens can distinguish true allergy from cross-reactivity to honey bee and yellowjacket venoms. Basophil activation tests can improve the detection of venom allergy and predict the severity of reactions and the efficacy of venom immunotherapy but are limited in availability. An elevated basal serum tryptase level is an important marker for severe sting anaphylaxis and underlying mast cell disorders (eg, hereditary α-tryptasemia and clonal mast cell disease). When there is high suspicion (eg, using the Red Espanola de Mastocytosis score), bone marrow biopsy is the definitive tool to characterize mast cell disorders that are associated with the most severe outcomes in patients with insect sting allergy.

Skin prick tests are not useful for the qualification for venom immunotherapy in children

Background

The basis for qualification for venom immunotherapy (VIT) is the fulfilment of both the clinical and immunological criteria. Diagnostic tests that confirm the immunological criterion of an IgE-mediated sensitization include skin prick tests (SPT), intradermal tests (IDT), and serum specific IgE (sIgE) for the culprit venom.

Objective

This study aimed to assess the usefulness of SPT as the immunological marker in the diagnosis of insect venom sensitization in children with history of systemic reaction (SR) to insect sting evaluated by means of I-IV-grades Mueller's scale. There are no such studies in children.

Methods

This cross-sectional study sample consisted of 416 children aged 3-18 years (mean age 10.6 ± 3.8), 76% males, all with the history of a systemic reaction (SR) after a Hymenoptera sting (48% of grade III/IV according to Mueller scale), diagnosed between 1999 and 2019 in the tertiary referral centre. The standard diagnostic tests were used. Specificity, sensitivity, and positive and negative predictive values were computed to assess the diagnostic properties of the clinical tests to distinguish between mild and severe SR. To assess the relative value of an individual test in predicting the qualification to VIT we incorporated the Shapley value (SV).

Results

Positive SPT results were found in up to no more than 3% of children; among them less than 1% had only positive SPT and were negative for sIgE and IDT. Approximately 85% of the children had detectable venom sIgE, followed by positive IDT (75%). Almost 70% of children had positive both sIgE and IDT results. In children with grade III/IV reaction, about 80% of children had positive results of both of these tests. sIgE and IDT had sensitivity >0.80, whereas SPT had high specificity (>0.97) in differentiating between mild and severe SR. Relative value of diagnostic tests in predicting qualification to VIT varied between venoms. Bee venom IDT had higher SV (0.052) than sIgE (0.041). In contrast, wasp venom sIgE had higher SV (0.075) than IDT (0.035).

Conclusion

SPTs are not an useful immunological marker of venom sensitization in children, and eliminating SPT does not result in a loss of diagnostic accuracy. Limiting diagnostics to venom sIgE and IDT would shorten the procedure and reduce costs. Future studies are needed to determine if venom sIgE as the first line diagnostic test, with IDT added only if the venom sIgE is undetectable, is an optimal diagnostic process.

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.

Molecular diagnostics and inhibition of cross‐reactive carbohydrate determinants in Hymenoptera venom allergy

Background

The composition of venom extracts, cross‐reactive carbohydrate determinants (CCD) and the component‐resolved diagnostics (CRD) are important fields of investigation. IgE‐reactivity to CCD complicates the interpretation of IgE to Hymenoptera venoms, especially in patients with multiple‐positivity. We analyzed the clinical importance of CRD and CCD‐inhibition for selection of allergens for venom immunotherapy (VIT).

Methods

In 71 patients, we measured specific IgE (sIgE) to honeybee venom (HBV), wasp venom (WV), hornet venom (HV), CCD, and recombinant allergens: phospholipase A2 (rApi m 1), hyaluronidase (rApi m 2), icarapin (rApi m 10), antigen 5 (rVes v 5), and phospholipase A1 (Immunoblot). In 29/71 HBV/WV/HV/CCD‐positive patients CCD‐inhibition was performed. According to CRD and CCD‐inhibition, we identified true sensitization and defined groups of multiple‐positive patients who needed CCD‐inhibition before starting VIT.

Results

sIgE‐rApi m 1, sIgE‐rApi m 2, and sIgE‐rApi m 10 were detected in 65.7%, 68.4%, and 58%, respectively. In HBV allergic patients, CRD sensitivity was 86.8%. In WV allergic patients, sensitivity of sIgE‐rVes v 5 was 94%. True multiple‐sensitization was found in 44.8% of HBV/WV/HV/CCD‐positive patients after CCD‐inhibition. Patients with multiple venom‐ and CCD‐positivity had more frequent severe allergic reactions (p < 0.001). CCD‐inhibition was helpful in HBV/WV/HV/CCD‐positive patients who were negative to all tested recombinant honeybee allergens. Persistence of HBV‐positivity after CCD‐inhibition requires CRD to other honeybee recombinant allergens.

Conclusion

CRD, using a profile of five most important recombinant allergens and CCD, has a high sensitivity for the diagnosis of venom allergy, especially in patients positive to several venom extracts. CRD and CCD‐inhibition are helpful to reveal the clinically relevant, true sensitization and improve the selection of venoms for long‐lasting VIT.

EAACI Molecular Allergology User's Guide 2.0

Since the discovery of immunoglobulin E (IgE) as a mediator of allergic diseases in 1967, our knowledge about the immunological mechanisms of IgE-mediated allergies has remarkably increased. In addition to understanding the immune response and clinical symptoms, allergy diagnosis and management depend strongly on the precise identification of the elicitors of the IgE-mediated allergic reaction. In the past four decades, innovations in bioscience and technology have facilitated the identification and production of well-defined, highly pure molecules for component-resolved diagnosis (CRD), allowing a personalized diagnosis and management of the allergic disease for individual patients. The first edition of the "EAACI Molecular Allergology User's Guide" (MAUG) in 2016 rapidly became a key reference for clinicians, scientists, and interested readers with a background in allergology, immunology, biology, and medicine. Nevertheless, the field of molecular allergology is moving fast, and after 6 years, a new EAACI Taskforce was established to provide an updated document. The Molecular Allergology User's Guide 2.0 summarizes state-of-the-art information on allergen molecules, their clinical relevance, and their application in diagnostic algorithms for clinical practice. It is designed for both, clinicians and scientists, guiding health care professionals through the overwhelming list of different allergen molecules available for testing. Further, it provides diagnostic algorithms on the clinical relevance of allergenic molecules and gives an overview of their biology, the basic mechanisms of test formats, and the application of tests to measure allergen exposure.

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: Long-term management and resources

Background: Anaphylaxis is an acute life-threatening event that requires emergent diagnosis and treatment. However, focus on prevention of anaphylaxis is essential in reducing anaphylaxis recurrences and associated mortality. Objective: This literature review was aimed to be a comprehensive resource for practicing allergists in managing anaphylaxis in the long term. We discussed the role of the allergist in the long-term outpatient management of anaphylaxis through identifying risk factors, allergen avoidance, prevention of recurrences, and patient education. Methods: A medical literature search that focused on several areas of long-term management of anaphylaxis was conducted. Results: Patients evaluated by an allergist are more likely to have their anaphylaxis trigger identified, to have their underlying mast cell disorder diagnosed, and to receive desensitization or allergen immunotherapy. Allergists can prevent fatal anaphylaxis by preventing and treating anaphylaxis in patients with ischemic heart disease and by optimally treating patients with comorbid asthma. Allergists can offer specific prevention strategies for allergenic trigger and cofactor avoidance. Education should be focused on patients with a higher risk for recurrence of anaphylaxis, such as those patients with a history of severe symptoms or anaphylaxis, with a peanut and/or tree nut trigger, or with a history of asthma, or female gender. Patient counseling involves providing individualized action plans at each visit and discussing proper use, storage, and safety of epinephrine autoinjectors. Multiple doses of epinephrine need to be prescribed to those who are at risk for severe food-induced, venom immunotherapy-related, or venom-induced anaphylaxis. Wording on medical identification products should be reviewed by the allergist. Anaphylaxis resources for health-care providers are summarized in the article. Conclusion: Ongoing education, providing personalized anaphylaxis action plans, reducing risk factors, and avoiding triggers are key to anaphylaxis prevention and long-term management.

Long-term adherence to imported fire ant subcutaneous immunotherapy

BACKGROUND

Imported fire ant (IFA) whole-body extract subcutaneous immunotherapy (IT) is a safe and effective treatment for IFA hypersensitivity, with a recommended length of treatment of 3 to 5 years.

OBJECTIVE

To evaluate long-term IFA IT adherence in patients with IFA allergy living in an endemic area.

METHODS

During 2007 to 2014, patients with IFA-sting systemic reactions and a recommendation to start IFA IT were prospectively enrolled in this study. Subjects were contacted annually for interval IT adherence. Institutional review board approval was obtained.

RESULTS

A total of 87 subjects, ages 2 to 64 years, with a recommendation to initiate IFA IT, were enrolled. Subjects were predominantly adult (76%) and female (55%), and 30% had asthma. Of these patients, 77 (89%) initiated treatment within 1 year of recommendation; 18 (23%) adhered to a 3-year course; and 10 (13%) adhered to a 5-year course. At 3 years, there were no significant differences in adherence between male and female subjects (28% vs 19%, P = .33), children and adults (25% vs 22%, P = .79), or those with or without asthma (30% vs 20%, P = .31). Adherence in subjects with mild initial reactions was lower than in subjects with moderate-to-severe reactions (0% vs 25%, P = .05) at 3 years only. Conventional buildup and concurrent flying Hymenoptera venom immunotherapy were predictive of adherence. Reasons for discontinuation were relocation to a nonendemic area (29%) and inconvenience (27%).

CONCLUSION

This study showed poor long-term adherence to IFA IT at 3 and 5 years. Initial sting severity, buildup protocol, and concurrent flying Hymenoptera venom immunotherapy were predictors for long-term IT adherence.

Diagnosis and Management of Insect Allergy: Barriers and Facilitators in the United States

While guidelines recommend testing and treatment for patients with venom-induced anaphylaxis to prevent morbidity and mortality, significant barriers prevent most patients from receiving the evaluation and treatments that they need. This review examines these barriers in the United States along with the facilitators that can be used to overcome them.

Adverse reactions in venom immunotherapy protocols: conventional versus ultra-rush

BACKGROUND

Venom immunotherapy (VIT) is an effective treatment in the patients at high risk of anaphylaxis or life-threatening systemic reactions due to Hymenoptera venom allergy. But, systemic and large local reactions can be observed, especially during the build-up phase of VIT. We evaluated the safety of conventional and ultra-rush build-up protocols.

MATERIALS AND METHODS

Two protocols in 71 patients (39 conventional and 32 ultra-rush protocols) with honeybee and wasp venom allergy were evaluated retrospectively. Patients were diagnosed and selected for VIT according to the criteria established by the European Academy of Allergy and Clinical Immunology. The severity of systemic reactions was evaluated according to the criteria of Mueller.

RESULTS

Build-up phases were tolerated in 66.2% (n = 47) without any reaction. Allergic adverse reactions were observed in 33.8% (n = 24): large local reactions 22.5% (n = 16) and systemic reactions 11.3% (n = 8). There was no significant difference in the number of adverse reactions comparing patients receiving conventional and ultra-rush protocol. In addition, no association was found between allergic adverse reactions and the following factors: sex, previous systemic sting reactions, honeybee and wasp venom extract.

CONCLUSION

We found that both protocols were tolerated in patients with honeybee and wasp venom allergy. Ultra-rush protocol will be preferred for patients and clinicians because of its advantages in terms of time and costs.KEY MESSAGESVIT is the only curative treatment method that reduces the risk of severe reactions after a bee sting and improves the quality of life in patients with Hymenoptera venom allergy.Ultra-rush VIT protocol has advantages such as few injection and time savings.Both ultra-rush and conventional VIT are safe treatments to prevent potentially life-threatening reactions in patients with honeybee and wasp venom allergy.

Diagnosis of Hymenoptera Venom Allergy: State of the Art, Challenges, and Perspectives

Hymenoptera venom allergy is the most common cause of anaphylaxis in adults and the second-most frequent in children. The proper diagnosis of this life-threatening allergy remains a challenge. This review focuses on the current knowledge regarding diagnostics of Hymenoptera venom allergy. The paper includes a brief description of the representatives of Hymenoptera order and the composition of their venoms. Then, diagnostic tests for allergy to Hymenoptera venom are described. Common diagnostic problems, especially double positivity in tests for IgE antibodies specific to honeybee and wasp venom, are also discussed. Special attention is paid to the search for new diagnostic capabilities using modern methodologies. Multidimensional molecular analysis offers an opportunity to characterize changes in body fluids associated with Hymenoptera venom allergy and yields a unique insight into the cell status. Despite recent developments in the diagnostics of Hymenoptera venom allergy, new testing methodologies are still needed to answer questions and doubts we have.

Peanut Oral Immunotherapy With or Without H1 and H2 Antihistamine Premedication for Peanut Allergy (PISCES): A Placebo-Controlled Randomized Clinical Trial

BACKGROUND

Current forms of peanut oral immunotherapy (OIT) are associated with side effects, and there is a lack of evidence addressing how to mitigate them.

OBJECTIVE

To determine whether premedication with desloratadine and ranitidine results in fewer side effects during peanut OIT/desensitization.

METHODS

A total of 43 patients with peanut allergy (mean age, 7.6 ± 2.1 years, 37% females, 63% males, baseline eliciting dose, 33 ± 26 mg) were randomized to OIT with or without concomitant H₁ and H₂ antihistamine blockade, or double-placebo. Patients, study staff/investigators, and statisticians were blinded. The primary outcomes were the frequency and severity of OIT-induced adverse events. The secondary outcomes were quality of life and eliciting doses to blinded food challenge.

RESULTS

Adverse reactions occurred more in the OIT groups compared with the double-placebo group (OIT with antihistamines vs double-placebo hazard ratio, 3.75 [95% CI, 2.79-4.72]; OIT with placebo antihistamines vs double-placebo, hazard ratio, 4.62 [95% CI, 3.61-5.62]). Patients given antihistamines cotreatment with OIT had a similar risk of adverse events compared with those who did not use antihistamines with OIT (hazard ratio, 1.23 [95% CI, 0.49-1.97]). OIT with and without antihistamines accelerated the incidence rate of adverse events compared with double-placebo (4.8 and 6.4 events per patient vs 3.5 per patient, incidence rate ratio, 2.49 [95% CI, 1.36-4.56] and 2.04 [95% CI, 1.01-4.15], respectively). Antihistamines pretreatment modestly reduced the frequency of moderate to severe adverse reactions among OIT-treated groups (1.9 per patient vs 4.2 per patient, incidence rate ratio, 0.46 [95% CI, 0.24-0.89]), primarily urticaria (0.6 vs 2.1 per patient) followed by abdominal pain (2.6 vs 4.2 per patient), but increased neuropsychiatric adverse events (primarily tiredness and sedation, 2.3 vs 0.7 per patient). Eliciting doses after treatment were similar in all groups. Quality of life improved similarly regardless of treatment with peanut OIT or placebo OIT.

CONCLUSIONS

Peanut OIT with antihistamines modestly reduce the skin and gastrointestinal components of the high incidence of adverse reactions during OIT, and there are no clear differences in improvement in quality of life whether treated with OIT, OIT with antihistamines, or placebo OIT despite OIT being effective in inducing desensitization. Safer food allergy treatment approaches that importantly improve quality of life need to be proved in future robust randomized trials.

Multisite evaluation of fire ant venom immunotherapy safety and efficacy

Background

Imported fire ant (IFA) venom immunotherapy (VIT) is the only disease-modifying treatment reported to be effective at decreasing the risk of systemic reactions (SRs) to IFA stings.

Objective

Our aims were to determine the baseline rates of IFA sensitization in subjects, describe IFA VIT prescribing patterns across the military health system (MHS), and retrospectively evaluate the safety and efficacy of IFA VIT.

Methods

We prospectively compared IFA sensitization in participants with and without an SR to flying Hymenoptera venom. Separately, IFA VIT prescription records were extracted from a centralized repository, and rates were described across the MHS. Additionally, we retrospectively reviewed the clinical course of patients being treated with IFA VIT at 11 military treatment facilities.

Results

The in vitro IFA sensitization rates in our prospective cohort ranged from 19.1% to 24.1%. Sensitization rates did not differ statistically between the subjects with or without an SR to flying Hymenoptera venom. We found that 60.9% of all MHS IFA VIT prescriptions (491 of 806) were from the 11 facilities in this study. We retrospectively identified 137 subjects actively undergoing IFA VIT. Among the subjects actively undergoing IFA VIT, 28 reported an SR to IFA venom and repeat stings by IFAs after reaching VIT maintenance, and 85.7% (24 of 28) of the subjects noted symptoms no worse than a large swelling reaction after a repeat IFA sting. Notably, only 2.9% of the subjects (4 of 137) had an SR due to VIT.

Conclusion

This study's results align with those of prior IFA sensitization reports. A substantial proportion of patients undergoing IFA VIT experienced protection against anaphylaxis with reexposure, with relatively few adverse events.

Venom allergen immunotherapy

Venom immunotherapy (VIT) with Hymenoptera venom extracts is highly effective in preventing large local, systemic allergic, and anaphylactic reactions to insect stings. VIT is not required for patients with cutaneous systemic or large local allergic reactions to stings because it is uncommon for reactions to become more severe. The clinical history, with confirmatory skin or serum tests for venom IgE, can clarify the risk for future anaphylaxis and the need for VIT. For initial treatment, rush regimens are recommended because they have the same or less risk of systemic reactions than slower traditional regimens. VIT is relatively safe with a low incidence of systemic reactions. Injection-site reactions can be bothersome but do not predict systemic reactions to venom injections. Patients who need VIT should be screened for baseline serum tryptase and possible underlying mast cell disorders. VIT can be discontinued after five years in most patients, but those with known high-risk factors should continue VIT indefinitely.

Anaphylactic reactions in the build-up phase of rush immunotherapy for bee venom allergy in pediatric patients: a single-center experience

Background

Anaphylaxis occurs in up to 3.5% of hymenoptera stings and can be a life-threatening emergency. Venom immunotherapy (VIT) provides excellent protection from further episodes of anaphylaxis and is well tolerated. In this study the frequency of anaphylactic reactions in pediatric patients undergoing rush bee venom immunotherapy was assessed as well as possible risk factors and modified up-dosing schemes are reported.

Methods

19 consecutive pediatric patients, who had previously experienced an anaphylactic reaction following a bee sting and showed IgE-mediated sensitization to bee venom, underwent inpatient rush immunotherapy with bee venom extract. We retrospectively compared serological findings (total IgE, serum tryptase level, sensitization to Api m1, Api m3 and Api m10 bee venom allergens) and possible risk factors between patients who experienced an anaphylactic reaction during immunotherapy and patients who did not.

Results

Three of the included 19 patients (15.8%) developed anaphylactic reactions to rush bee venom immunotherapy, all of them between administration of 40 and 80 µg of bee venom extract. However, all three patients reached the standard maintenance dose of 100 µg of bee venom following a modified VIT schedule without any further complications. Total serum IgE levels as well as Api m3 sensitization levels were significantly higher in patients showing an adverse reaction to bee VIT compared to those who did not experience any complications. There were no statistically significant differences concerning age, pre-existing conditions, type and severity of the initial reaction and Api m1, Api m10 and serum tryptase levels between the two subgroups.

Conclusion

Even if anaphylactic reactions occur during the build-up phase of VIT for bee venom in children and adolescents, venom immunotherapy can and should be continued in most cases.

What We Know about Sting-Related Deaths? Human Fatalities Caused by Hornet, Wasp and Bee Stings in Europe (1994-2016)

Simple Summary

Information about fatalities due to stinging insects is scarce. Hymenopteran-related deaths (n = 1691) in 32 European countries based on official registers over a 23-year period (1994–2016) are described. Male adults (25–64 years) were the most common group to be fatally injured and almost half of the fatalities were recorded at “unspecified places”. Fatalities per million inhabitants per year ranged from 0 to 2.24 with an average of 0.26. Geographic, environmental, and ecological factors influence the frequency of stings, and its subsequent reaction. It is necessary to produce and interpret knowledge using diverse sources and in an interdisciplinary way. As part of the One Health philosophy, people and hornets, wasps and bees, as well as the environment that they share are closely connected.

Abstract

Epidemiology of Hymenopteran-related deaths in Europe, based on official registers from WHO Mortality Database (Cause Code of Death: X23), are presented. Over a 23-year period (1994–2016), a total of 1691 fatalities were recorded, mostly occurring in Western (42.8%) and Eastern (31.9%) Europe. The victims tended to concentrate in: Germany (n = 327; 1998–2015), France (n = 211; 2000–2014) and Romania (n = 149; 1999–2016). The majority of deaths occurred in males (78.1%) between 25–64 years (66.7%), and in an “unspecified place” (44.2%). The highest X23MR (mortality rate) were recorded in countries from Eastern Europe (0.35) followed by Western (0.28), Northern (0.23) and Southern Europe (0.2). The countries with the highest and lowest mean X23MR were Estonia (0.61), Austria (0.6) and Slovenia (0.55); and Ireland (0.05), United Kingdom (0.06) and the Netherlands (0.06), respectively. The X23 gender ratio (X23GR; male/female) of mortality varied from a minimum of 1.4 for Norway to a maximum of 20 for Slovenia. Country-by-country data show that the incidence of insect-sting mortality is low and more epidemiological data at the regional level is needed to improve our understanding of this incidence. With the expansion of non-native Hymenopteran species across Europe, allergists should be aware that their community’s exposures are continually changing

Use of biologics for the treatment of moderate-to-severe asthma: the age of personalized medicine

PURPOSE OF REVIEW

There are multiple FDA-approved biologics to treat poorly controlled moderate-to-severe asthma. Given the heterogeneity of asthma and the lack of head-to-head data between biologics, selecting the best biologic for a patient can be difficult. This review summarizes the key literature to date, in hopes of facilitating an evidence-based approach to selecting the most appropriate biologic for patients with asthma.

RECENT FINDINGS

In addition to unique mechanisms of action, there is increasing literature on predictors of response to each biologic, such as sensitizations to aeroallergens, peripheral eosinophil count, total serum IgE, and exhaled nitric oxide. Biologics available for asthma are also being increasingly studied in comorbid conditions with asthma, and this may facilitate selecting the most appropriate biologic for a patient. In the absence of head-to-head studies, there is literature of switching between biologics whenever necessary.

SUMMARY

The authors outline an approach to selecting a biologic based on various considerations, and hope this suggested approach facilitates selecting the biologic most suitable for each individual with poorly controlled moderate-to-severe asthma.

Update on omalizumab in allergen immunotherapy

PURPOSE OF REVIEW

To review the most relevant studies in the advancing field of omalizumab in allergen immunotherapy.

RECENT FINDINGS

Omalizumab has been used in combination with inhalant, venom, and food allergen immunotherapy. These studies suggest that omalizumab can decrease the time required to reach maintenance dosing and adverse events. However, severe adverse events do still occur. Limited long-term data suggests that there is a risk for increased reactivity after stopping omalizumab.

SUMMARY

Omalizumab in conjunction with immunotherapy has shown promising results for the treatment of allergic rhinitis, venom hypersensitivity, and food allergy, especially in the reduction of adverse events. Larger randomized, placebo-controlled trials are needed to better understand optimal dosing and duration, cost--benefit analysis, ideal patients, and long-term benefits. This combination therapy has the potential to improve treatment, particularly for high-risk patients.

Anaphylaxis to Stinging Insect Venom

Hymenoptera stinging insects are common culprits for allergic reactions. Anaphylaxis to insect stings can be life threatening and is associated with a significant risk of recurrence. Insect allergy requires referral to an allergist/immunologist for education and for diagnostic evaluation that will direct further management and treatment. Venom immunotherapy is safe and effective; it prevents sting anaphylaxis in up to 98% of patients. Potential risk factors for side effects during testing and treatment should be assessed for every patient to mitigate risk and to guide treatment recommendations and the duration of immunotherapy.

Differential uptake of three clinically relevant allergens by human plasmacytoid dendritic cells

Background

Human plasmacytoid dendritic cells (pDC) have a dual role as interferon-producing and antigen-presenting cells. Their relevance for allergic diseases is controversial. and the impact of pDC on allergic immune responses is poorly understood.

Methods

This in vitro study on human pDC isolated from peripheral blood was designed to compare side by side the uptake of three clinically relevant representative allergens: fluorochrome-labeled house dust mite Der p 1, Bee venom extract from Apis mellifera (Api) and the food allergen OVA analyzed flow cytometry and confocal microscopy.

Results

We found that the internalization and its regulation by TLR9 ligation was significantly different between allergens in terms of time course and strength of uptake. Api and OVA uptake in pDC of healthy subjects was faster and reached higher levels than Der p 1 uptake. CpG ODN 2006 suppressed OVA uptake and to a lesser extent Der p 1, while Api internalization was not affected. All allergens colocalized with LAMP1 and EEA1, with Api being internalized particularly fast and reaching highest intracellular levels in pDC. Of note, we could not determine any specific differences in antigen uptake in allergic compared with healthy subjects.

Conclusions

To our knowledge this is the first study that directly compares uptake regulation of clinically relevant inhalative, injective and food allergens in pDC. Our findings may help to explain differences in the onset and severity of allergic reactions as well as in the efficiency of AIT.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12948-021-00163-8.

Anaphylaxis in Children and Adolescents

Anaphylaxis is an acute, potentially life-threatening systemic hypersensitivity reaction. Classically, anaphylaxis is an immunoglobulin (Ig) E-mediated reaction; however, IgG or immune complex complement-related immunologic reactions that lead to degranulation of mast cells can also cause anaphylaxis. Food allergy is the most common cause of anaphylaxis, followed by drugs. Patients with anaphylaxis commonly present with symptoms involving skin or mucous membranes, followed by respiratory and gastrointestinal symptoms. Epinephrine is the drug of choice for treating anaphylaxis. Patients and caregivers should be educated on the use of epinephrine autoinjectors with periodic review of symptoms and emergency action plan for anaphylaxis.

Combining Discordant Serum IgE and Skin Testing Improves Diagnostic and Therapeutic Accuracy for Hymenoptera Venom Hypersensitivity Immunotherapy

BACKGROUND

Diagnosis of patients with hymenoptera venom hypersensitivity consists of elucidating clinical symptoms suggestive of systemic reaction (SR) and then confirmation of sensitization via intradermal skin testing (IDST) first and serum IgE assays such as ImmunoCAP (ICAP) as a complementary modality of diagnosis.

OBJECTIVE

Determine the concordance between ICAP and IDST in patients with a clinical history suggestive of hymenoptera venom SR. Determine whether venom immunotherapy would change on the basis of IDST versus ICAP results.

METHODS

A prospective diagnostic study was designed to test the concordance between IDST and ICAP venom testing in the diagnosis of hymenoptera venom hypersensitivity. This study entailed testing both IDST and ICAP for 5 hymenoptera venoms (honey bee, wasp, yellow jacket, yellow hornet, and white-faced hornet) in both a case group with SR to hymenoptera venom (N = 70) and a control group without SR (N = 51).

RESULTS

Significant discordance was observed between positive IDST and ICAP results for any of the 5 hymenoptera venoms (McNemar test, P = .001). In the case group, there was significant discordance for wasp (P < .0001), yellow jacket (P = .002), and white-faced hornet (P = .02). More than 47% of the case patients would have different venom immunotherapy prescriptions if ICAP and IDST had been performed during initial diagnosis versus IDST alone.

CONCLUSIONS

Our study shows significant discordance between IDST and ICAP; however, they are complementary. On the basis of our data, we propose ICAP testing first followed by IDST for ICAP-negative venoms as an alternative and efficient diagnostic strategy.

Pregnancy and Hymenoptera venom allergy

PURPOSE OF REVIEW

To evaluate the indication to perform venom immunotherapy (VIT) during pregnancy considering the risks of adverse events during the build-up phase or the maintenance phase and analyzing specific articles and guidelines on VIT.

RECENT FINDINGS

Only few studies treat this argument and literature only counts one recent study on the topic, whereas recent guidelines state the behavior to keep in pregnancy.

SUMMARY

Hymenoptera venom allergy (HVA) affects about 7.5% of the European population. VIT is the only effective disease-modifying treatment for patients presenting anaphylactic reactions. VIT counts several mechanisms of action, with the increase of IgG1 and IgG4 and a cytokine impairment inducing a Th2-Th1 shift. Pregnancy is a health condition where a Th2 profile is required to prevent fetal rejection, so VIT could be a problem for the fetus when started during pregnancy.

A Review of Honeybee Venom Allergens and Allergenicity

Honeybee venom is a source of proteins with allergenic properties which can result in in various symptoms, ranging from local reactions through to systematic life-threatening anaphylaxis, or even death. According to the World Allergy Organization (WAO), honeybee venom allergy is one of the most common causes of anaphylaxis. Among the proteins present in honeybee venom, 12 protein fractions were registered by the World Health Organization’s Allergen Nomenclature Sub-Committee (WHO/IUIS) as allergenic. Most of them are highly immunogenic glycoproteins that cross-react with IgE and, as a consequence, may give false positive results in allergy diagnosis. Allergenic fractions are different in terms of molecular weight and biological activity. Eight of these allergenic fractions have also been identified in honey. This explains frequent adverse reactions after consuming honey in people allergic to venom and sheds new light on the causes of allergic symptoms in some individuals after honey consumption. At the same time, it also indicates the possibility of using honey as a natural source of allergen in specific immunotherapy.

Routine KIT p.D816V screening identifies clonal mast cell disease in patients with Hymenoptera allergy regularly missed using baseline tryptase levels alone

BACKGROUND

Clonal mast cell disorders and elevated basal serum tryptase (BST) levels with unknown cause(s) are associated with severe Hymenoptera venom-triggered anaphylaxis (HVA). However, some individuals with clonal disease have a normal BST level (<11.4 ng/mL).

OBJECTIVE

Our aim was to evaluate whether screening for KIT p.D816V in the blood is a useful clinical tool to risk-stratify patients with venom allergy.

METHODS

We prospectively recruited 374 patients with Hymenoptera allergy and no overt signs of mastocytosis who were referred to our center during the years 2018 and 2019. KIT p.D816V was determined in their peripheral blood by quantitative PCR, and tryptase genotyping was performed by droplet digital PCR.

RESULTS

In all, 351 patients (93.9%) had normal levels of BST, and KIT p.D816V was detected in 8% of patients (28 of 351), predominantly in patients with the most severe Mueller grade IV anaphylaxis (18.2% [24 of 132] vs 1.8% in patients with lower grades [4 of 88 with grade III and 0 of 131 with other grades]; P < .001). In grade IV patients with a normal BST level, KIT p.D816V was associated with more severe symptoms, including a significantly higher frequency of loss of consciousness (58.3% [14 of 24] vs 34.3% [37 of 108]; P = .03) and absence of skin symptoms (41.7% [10 of 24] vs 15.7% [17 of 108]; P = .004). Among patients with a normal BST level, KIT p.D816V (OR = 10.25 [95% CI = 3.75-36.14]; P < .0001) was the major risk factor associated with severe HVA. Hereditary α-tryptasemia (HαT) due to increased germline copies of TPSAB1 encoding α-tryptase was the most common cause (65.2% [15 of 23]) of elevated BST level in patients with HVA, and together with KIT p.D816V, it accounted for 90% of BST level elevations (20 of 23) in patients with HVA.

CONCLUSION

These results indicate that routine KIT p.D816V screening identifies clonal disease in high-risk patients with HVA who are regularly missed when BST level is used alone.

Reducing the sting: Diagnosis and management of Hymenoptera venom allergy

ABSTRACT

Hymenoptera species include stinging insects such as wasps, hornets, bees, and fire ants. Allergic reaction to the venom of these insects is a common presenting complaint for patients in primary care and emergency medicine during warmer months. Patients' clinical presentations may vary, and clinicians must identify the type of reaction to determine treatment and follow-up plans. Treatment of patients allergic to Hymenoptera venom should be individualized based on risk factors, reaction type, and associated comorbidities. This article reviews common features of clinical presentation, diagnosis, and the current mainstays in management of Hymenoptera venom allergy.

The Revenge of Unintended Consequences of Anaphylaxis-Risk Overdiagnosis: How Far We Have Come and How Far We Have to Go

Overdiagnosis of anaphylaxis risk is an underappreciated aspect of anaphylaxis prevention. Whereas the benefits of anaphylaxis-risk prevention are well known, potential harms resulting from preemptive approaches to mitigate anaphylaxis-risk are not insignificant. Still, great progress has been made in recent years to avoid the unintended consequences of anaphylaxis-risk overdiagnosis. Reflection on recent advances in the use of diagnostic testing, as well as the application of diagnostic labels, provides an important perspective to understand how far the specialty of allergy and immunology has come in improving the lives of patients and families. Examples of recent paradigm shifts in anaphylaxis-risk management include approaches to peanut allergy prevention without screening, deferral of corticosteroids to prevent biphasic anaphylaxis reactions, reevaluation of reflex use of emergency medical services for resolved community anaphylaxis, and an approach to penicillin allergy delabeling with direct oral challenge. Routine medical practices to decrease anaphylaxis risk can have lifelong impacts for patients-beyond just preventing anaphylaxis. As our understanding of these trade-offs evolves, it becomes necessary to weigh both the benefits and the harms of past management approaches. Because medicine remains a science of uncertainty and an art of probability, a critical approach to risk mitigation remains necessary to find the often-elusive balance in anaphylaxis prevention.

Global View on Ant Venom Allergy: from Allergenic Components to Clinical Management

Hymenoptera venom allergy is characterised by systemic anaphylactic reactions that occur in response to stings from members of the Hymenoptera order. Stinging by social Hymenoptera such as ants, honeybees, and vespids is one of the 3 major causes of anaphylaxis; along with food and drug exposure, it accounts for up to 43% of anaphylaxis cases and 20% of anaphylaxis-related fatalities. Despite their recognition as being of considerable public health significance, stinging ant venoms are relatively unexplored in comparison to other animal venoms and may be overlooked as a cause of venom allergy. Indeed, the venoms of stinging ants may be the most common cause of anaphylaxis in ant endemic areas. A better understanding of the natural history of venom allergy caused by stinging ants, their venom components, and the management of ant venom allergy is therefore required. This article provides a global view on allergic reactions to the venoms of stinging ants and the contemporary approach to diagnose and manage ant venom allergy.