Self-medication of anaphylactic reactions due to Hymenoptera stings-an EAACI Task Force Consensus Statement

Hymenoptera venom allergy in children and adolescents

PURPOSE OF REVIEW

This review will identify and summarize the published existing data pertaining specifically to Hymenoptera venom allergy in children and adolescents, highlighting the major studies currently available on venom immunotherapy (VIT) and its prognosis in children.

RECENT FINDINGS

The current review covers the incidence and prevalence of Hymenoptera venom allergy (HVA) in children, factors influencing occurrence and severity of reactions (age, sex, comorbidities, etc.), indications to perform diagnostic tests and start VIT in children, different existing VIT protocols and their safety and efficacy.

SUMMARY

Hymenoptera venom allergy is the second most common cause of anaphylaxis in children and it considerably affects quality of life. Cutaneous reactions are the most prevalent clinical presentation in children who usually have a more favourable prognosis than adult patients. However, studies on HVA in children and adolescents are still limited. Currently VIT is the only treatment able to modify the natural history of HVA in adults as well as in children, and to protect patients from systemic reactions after subsequent stings.

Age- and Elicitor-Dependent Characterization of Hymenoptera Venom-Induced Anaphylaxis in Children and Adolescents

BACKGROUND

Hymenoptera venom is one of the most frequent causes of anaphylaxis. Studies from adults indicate the clinical profiles and risk factors of Hymenoptera venom-induced anaphylaxis (VIA). Much less is known about pediatric VIA.

OBJECTIVE

To understand elicitor- and age-related factors determining pediatric VIA by analyzing data from the anaphylaxis registry.

METHODS

We selected pediatric VIA, pediatric food-induced anaphylaxis (FIA), and adult VIA cohorts from the anaphylaxis registry and performed a comparative data analysis regarding elicitors, symptoms, and management.

RESULTS

We identified 725 pediatric patients with VIA, 3,149 with pediatric FIA, and 5,534 with adult VIA. In pediatric VIA, boys were more frequently affected, atopy was not increased, and the onset of the reaction after exposure was fast (≤30 min; 91%) compared with pediatric FIA. Symptoms in pediatric VIA were age dependent, and although respiratory symptoms occurred most frequently besides skin symptoms in both pediatric patients with VIA and FIA, cardiovascular symptoms were more frequently reported in pediatric patients with VIA than pediatric patients with FIA. The analysis of pediatric versus adult VIA revealed clear differences in the frequency of involved organ systems (skin: 93% vs 78%; respiratory: 77% vs 64%; and cardiovascular: 61% vs 85%). For both pediatric and adult VIA, the rates of adrenaline application by a professional were low (29% vs 31%) but hospitalization rates were higher in children than in adults (61% vs 42%). Venom immunotherapy was frequently initiated regardless of age (78% each).

CONCLUSIONS

Pediatric VIA is more frequent in boys, symptoms are age dependent, and hospitalization is often required. Adrenaline should be applied according to current guidelines. Venom immunotherapy is an important treatment option in pediatric VIA and should be considered in severely affected children.

Should Patients With a Large Local Reaction be Offered Venom Immunotherapy? A Pro-Con Debate

Insect stings can cause large local reactions (LLRs) that are IgE-mediated and associated with considerable morbidity. A risk for systemic reactions including anaphylaxis to subsequent stings has been reported and is often noted by patients and health care providers. Guidelines do not recommend venom immunotherapy (VIT) for LLRs based on the relatively low risk of anaphylaxis, but this is debated in this review. On the pro side: the risk of anaphylaxis may be higher than reported in the limited literature, especially in patients who had only 1 LLR; new species with more potent stings are spreading into new areas; the quality of life can be markedly impaired by LLRs; and VIT is generally safe and highly effective. On the con side: LLRs are benign, stings occur infrequently, VIT has significant cost, systemic reactions occur more often to VIT than to stings in patients with LLRs, and Food and Drug Administration approval and published guidelines do not recommend VIT for LLRs. In practice, shared decision-making is appropriate to incorporate knowledge of the natural history and known high-risk factors in the context of the patient's personal values and preferences.

Risk Factors Associated with Severe Systemic Allergic Reaction after Wasp Sting in Subjects with a History of European Hornet Sting Allergy

Aim

To make the treatment approach in patients suffering a European hornet sting allergy reaction more personalized, preparing them also for possible future risks.

Methods

In Slovenia an extended retrospective observational cohort epidemiological study about the natural history of Hymenoptera venom sensitivity is in progress. The study is based on data from the healthcare records of the University Clinic Golnik (UCG) and data collected by a questionnaire sent to patients from May 2019 to April 2021. For a pilot study, we selected patients who were referred to UCG because of an allergic reaction to European hornet sting and had been re-stung later by a wasp (n=68). The association between severe systemic allergic reactions (SSAR) after wasp sting and potential risk factors in subjects with a history of hornet sting allergy was assessed univariately using the likelihood ratio test.

Results

Among 68 European hornet allergic patients 27 reacted with an SSAR and 41 reacted with a mild SAR. Among 27 patients with SSAR, 4 reacted with an SSAR also to a subsequent wasp sting. Among 41 patients with a mild European hornet sting SAR nobody reacted with an SSAR to a subsequent wasp sting. The association between the severity of the wasp SAR reaction in European hornet allergic patients was statistically significant (p=0.022).

Conclusion

Our results suggest that patients with severe European hornet SAR should be considered for wasp venom immunotherapy or prophylactic prescription of epinephrine auto-injector as they are at risk for an SSAR also after wasp string.

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.

Health-related quality of life in food and venom induced anaphylaxis and role of influencing factors

The impact on health-related quality of life (HRQL) plays a key role for patients suffering from allergies and anaphylaxis. In this narrative review we review the HRQL in allergic patients suffering from food and venom allergy, both being the most frequent elicitors of severe allergic, potential life-threatening reactions and provide an overview on the current knowledge and identified gaps. The data show that for food and venom allergy standardized assessment tools to measure HRQL are available and have been successfully applied. Our analysis shows that multiple factors can modulate HRQL in these patient groups. These include sociodemographic data like patients' age and sex, fear of accidental reactions but also external factors like the social environment and the appreciation of the seriousness of the condition by others. External factors may have a significant impact on HRQL and should be considered in patient-related outcome assessments to avoid biased measurements possibly affecting the results. The assessment of the quality of life in the context of specific immunotherapy should consider lifestyle factors and ideally, the individual change in HRQL should be measured. Although there are many data indicating a negative impact on HRQL in food allergic children and their caregivers, limited data are existing from adults with food allergy and venom allergic patients from all age groups. Also, the use of standardized questionnaires should be extended to allow for a better comparability of results between studies. Therefore, translation to additional languages is necessary. Taken together, the eliciting allergen, the severity of the allergic disease but moreover multiple external factors impact the outcome in HRQL and should be considered in HRQL assessment.

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.

Idiopathic Anaphylaxis? Analysis of Data from the Anaphylaxis Registry for West Pomerania Province, Poland

The most common causes of anaphylaxis, according to various authors and depending on the age of the studied groups, are: Hymenoptera venom, food, and medications. Unfortunately, we are not always able to indicate the cause of anaphylaxis. There are data in the literature where as many as 41% of all cases are idiopathic anaphylaxis. Since the introduction of new diagnostic methods such as molecular diagnostics (MD) in our centre, the percentage of idiopathic anaphylaxis in the Anaphylaxis Register has significantly decreased. The purpose of this study was to identify possible causes of idiopathic anaphylaxis in patients with a history of moderate to severe anaphylactic reactions. After using MD, the causative agent was found in another 29 people. The proportion of people with idiopathic anaphylaxis in the Registry decreased from 9.2% to 3.5%. There were no significant differences in the incidence, although men appear to be slightly more common in primary idiopathic anaphylaxis. The mean age of primary idiopathic anaphylaxis was 40 years, but this was as high as 51 for anaphylaxis with alpha-gal allergy. Exercise may or may not be present as a cofactor despite its established role, e.g., in wheat-dependent exercise-induced anaphylaxis (WDEIA). In most of the analyzed cases, i.e., 70%, the reaction took place within an hour. The longest time interval from exposure to the development of symptoms is in the case of alpha-gal allergy; in this analysis, it was at least 5 h after ingestion of the so-called "red meat". Patients are not aware of the disease, or further attacks cannot be prevented. As many as 80% had idiopathic anaphylaxis prior to visiting the centre, and 80% developed anaphylaxis after visiting the centre, which emphasizes the need to not stop the medical team in their search for the causes. As many as 93% of cases required medical intervention, of which adrenaline was used only in 34.5%, antihistamines in 86%, systemic glucocorticosteroids (sCS) in 75%, and fluids in 62% of cases. A total of 83% of patients received an emergency kit for self-administration. Idiopathic anaphylaxis can be resolved as known-cause anaphylaxis after a thorough medical history and, if possible, without exposing the patient after using appropriate, modern in vitro diagnostic methods, including molecular diagnostics. The diagnosis of idiopathic anaphylaxis should extend the diagnosis to include alpha-gal syndrome, LTP syndrome and WDEIA.

Anaphylaxis in elderly people

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

EAACI guidelines: Anaphylaxis (2021 update)

Anaphylaxis is a clinical emergency which all healthcare professionals need to be able to recognize and manage. The European Academy of Allergy and Clinical Immunology Anaphylaxis multidisciplinary Task Force has updated the 2014 guideline. The guideline was developed using the AGREE II framework and the GRADE approach. The evidence was systematically reviewed and recommendations were created by weighing up benefits and harms. The guideline was peer-reviewed by external experts and reviewed in a public consultation. The use of clinical criteria to identify anaphylaxis is suggested with blood sampling for the later measurement of tryptase. The prompt use of intramuscular adrenaline as first-line management is recommended with the availability of adrenaline autoinjectors to patients in the community. Pharmacokinetic data should be provided for adrenaline autoinjector devices. Structured, comprehensive training for people at risk of anaphylaxis is recommended. Simulation training and visual prompts for healthcare professionals are suggested to improve the management of anaphylaxis. It is suggested that school policies reflect anaphylaxis guidelines. The evidence for the management of anaphylaxis remains mostly at a very low level. There is an urgent need to prioritize clinical trials with the potential to improve the management of patients at risk of anaphylaxis.

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

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

Bone Marrow Mastocytosis: A Diagnostic Challenge

Bone marrow mastocytosis (BMM) represents a provisional, indolent subvariant of systemic mastocytosis (SM). Utilizing WHO criteria, BMM requires bone marrow (BM) involvement and the absence of mastocytosis skin lesions. BMM is characterized by male sex prevalence, a slight increase of serum tryptase levels, low BM mast cells (MC) burden, and an indolent clinical course. BMM shows a strong correlation with severe anaphylaxis, mainly due to an IgE-mediated allergy to bee or wasp venom and, less frequently, to unexplained (idiopathic) anaphylaxis. Furthermore, BMM is often associated with osteoporosis which could be the only presenting symptom of the disease. BMM is an undervalued disease as serum tryptase levels are not routinely measured in the presence of unexplained osteoporosis or anaphylaxis. Moreover, BMM patients are often symptom-free except for severe allergic reactions. These factors, along with typical low BM MCs infiltration, may contribute to physicians overlooking BMM diagnosis, especially in medical centers that lack appropriately sensitive diagnostic techniques. This review highlights the need for a correct diagnostic pathway to diagnose BMM in patients with suspected symptoms but lacking typical skin lesions, even in the case of normal serum tryptase levels. Early diagnosis may prevent potential life-threatening anaphylaxis or severe skeletal complications.

Molecular Background, Clinical Features and Management of Pediatric Mastocytosis: Status 2021

Pediatric mastocytosis is a heterogeneous disease characterized by accumulation of mast cells in the skin and less frequently in other organs. Somatic or germline mutations in the KIT proto-oncogene are detected in most patients. Cutaneous mastocytosis is the most common form of the disease in children. In the majority of cases, skin lesions regress spontaneously around puberty. However, in few patients, mastocytosis is not a self-limiting disease, but persists into adulthood and can show signs of systemic involvement, especially when skin lesions are small-sized and monomorphic. Children with mastocytosis often suffer from mast cell mediator-related symptoms. Severe hypersensitivity reactions can also occur, mostly in patients with extensive skin lesions and blistering. In a substantial number of these cases, the triggering factor of anaphylaxis remains unidentified. Management of pediatric mastocytosis is mainly based on strict avoidance of triggers, treatment with H1 and H2 histamine receptor blockers, and equipment of patients and their families with epinephrine auto-injectors for use in severe anaphylactic reactions. Advanced systemic mastocytosis occurs occasionally. All children with mastocytosis require follow-up examinations. A bone marrow investigation is performed when advanced systemic mastocytosis is suspected and has an impact on therapy or when cutaneous disease persists into adulthood.

Effects of a 90-min educational intervention for patients with insect venom allergy: a prospective controlled pilot study

Background

Anaphylactic sting reactions need a prompt management. A structured educational intervention for patients with insect sting allergy has not been implemented so far. The purpose of this study was to analyze the effects of a structured 90-min educational intervention for patients with insect sting allergy.

Methods

Patients with an insect venom allergy were offered to participate in a structured 90-min group education (intervention group (IG)) or to attend a control group (CG). The patients’ subjective self-assurance in using the emergency medication, the willingness to always carry the emergency medication, the mental health status, absolute one-time willingness-to-pay (WTP) for complete cure, a disease knowledge assessment and a simulation test to examine the ability to manage an acute sting reaction were estimated at baseline (t0) and at follow-up (t1) as outcome parameters.

Results

55 patients participated in the IG (n = 25, 52.0% female, mean age 55.9 years) or the CG (n = 30, 56.7% female, mean age 52.0 years). Both arms showed a significant gain in self-assurance in using the emergency medication (IG: 6.1 at t0 vs. 8.6 at t1, p < 0.0001 and CG: 7.1 vs. 8.0, p = 0.0062) and ability to manage an acute sting reaction (IG: 6.7 vs. 11.4, p < 0.0001 and CG: 9.0 vs. 10.5, p = 0.0002) at t1. However, trained participants showed a significantly higher gain in the respective parameters. There were no significant changes regarding the remaining examined outcome parameters.

Conclusions

Patients who are willing to invest 90 min in a patient education intervention benefit significantly by an increased subjective and objective empowerment to manage an acute sting reaction.

Benefits and limitations of sting challenge in hymenoptera venom allergy

The prevalence of systemic reactions to hymenoptera stings is up to 7.5%. Venom-specific immunotherapy (VIT) is an established treatment for insect venom allergy. In order to monitor the allergic status and thus the success of the therapy, controlled sting challenge under VIT continues to be the gold standard. This review deals not only with useful indications and therapeutic consequences but also with critical aspects that should be considered when performing sting challenge.

Precision Medicine in Hymenoptera Venom Allergy: Diagnostics, Biomarkers, and Therapy of Different Endotypes and Phenotypes

Allergic reactions to stings of Hymenoptera species may be severe and are potentially fatal deviations of the immunological response observed in healthy individuals. However, venom-specific immunotherapy (VIT) is an immunomodulatory approach able to cure venom allergy in the majority of affected patients. An appropriate therapeutic intervention and the efficacy of VIT not only depend on a conclusive diagnosis, but might also be influenced by the patient-specific manifestation of the disease. As with other diseases, it should be borne in mind that there are different endotypes and phenotypes of venom allergy, each of which require a patient-tailored disease management and treatment scheme. Reviewed here are different endotypes of sting reactions such as IgE-mediated allergy, asymptomatic sensitization or a simultaneous presence of venom allergy and mast cell disorders including particular considerations for diagnosis and therapy. Additionally, phenotypical manifestations of venom allergy, as e.g. differences in age of onset and disease severity, multiple sensitization or patients unsusceptible to therapy, are described. Moreover, biomarkers and diagnostic strategies that might reflect the immunological status of the patient and their value for therapeutic guidance are discussed. Taken together, the increasing knowledge of different disease manifestations in venom hypersensitivity and the growing availability of diagnostic tools open new options for the classification of venom allergy and, hence, for personalized medical approaches and precision medicine in Hymenoptera venom allergy.

Natural history and long-term follow-up of Hymenoptera allergy

PURPOSE OF REVIEW

Information on the natural history of hypersensitivity reactions is helpful for deciding which patient urgently needs a venom immunotherapy (VIT).

RECENT FINDINGS

The frequency of self-reported systemic allergic reactions (SAR) to Hymenoptera stings is approximately 3-7% in the Northern Hemisphere. About 25% of SAR are severe (anaphylactic shock). Fatal sting reactions are very rare. The most important risk factor for severe insect sting anaphylaxis is mast cell disease. Other risk factors are higher age, vespid venom allergy (in contrast to honeybee venom allergy), repeated stings, male sex, and treatment with ACE inhibitors. Preceding large local reactions seem not to play a risk factor for subsequent SAR.

SUMMARY

The majority of risk factors for severe anaphylaxis are not modifiable. For patients presenting with well defined risk factors for a very severe or even fatal anaphylaxis, VIT is of utmost importance, and they should be performed for the rest of their life. Sting challenge tests are required to identify patients in whom treatment was ineffective. Those patients, who did not receive VIT although presenting with a firm indication, or in whom VIT was stopped, require yearly monitoring to teach preventive measures and to renew the emergency kit.

Honeybee Stings in the Era of Killer Bees: Anaphylaxis and Toxic Envenomation

BACKGROUND

Twenty-six years after the arrival of "killer bees" in Arizona, the entire state with the exception of high elevations in the north is populated with this bee variety and 11 people have died at the scene of massive bee attacks.

METHODS

Because of the aggressive behavior of these bees we studied bee stings reported to the Arizona Poison and Drug Information Center. The center received 399 calls regarding 312 victims of bee stings from January 2017 to June 2019. Calls originated from private residences and emergency centers.

RESULTS

Stings occurred at victims' home residences in 272 (84.7%) of cases and 24 (7.5%) in public areas; 251 people suffered 1 sting; 42 individuals, 2-10 stings, 4 had 11-49 stings, and 13 individuals had >50 stings (so-called massive stinging). Three individuals were admitted to intensive care units (ICU) and one 35-year-old man died of anaphylaxis after 1 sting; moderate clinical effects occurred in 32 individuals including 6 admitted to the hospital but not in the intensive care unit. Anaphylaxis occurred in 30 (9.6%) of individuals, 16 receiving 1 sting. Toxic effects, tachycardia, elevated creatinine, or rhabdomyolysis occurred in 13 (4.2%) individuals.

CONCLUSIONS

In the past, individuals stung more than 50 times were beekeepers working with European honeybees, whereas, in the current era, single as well as massive stings are the result of feral "killer bees." This change in epidemiology requires a new approach to sting victims: those with massive stinging should be evaluated and observed for anaphylaxis and serial laboratory values obtained for days to detect the toxic effects of envenomation.

Development of a model care pathway for the management of Hymenoptera venom allergy: evidence-based key interventions and indicators

BACKGROUND

Hymenoptera venom allergy (HVA) is an underestimated condition representing an important cause of morbidity and mortality worldwide. Preventing future allergic reactions in patients who have already developed a systemic reaction is based on the correct management of the acute phase of the reaction followed by a correct diagnosis and, where indicated, prescription of adrenaline autoinjectors and VIT. A possible strategy to optimize care processes and to improve outcomes is the implementation of a Diagnostic and Therapeutic Care Pathways, also known as Integrated Care Pathways or Clinical Pathways (CPWs). The aim of the care pathway is to enhance the quality of care by improving risk-adjusted patient outcomes, promoting patient safety, increasing patient satisfaction, and optimizing the use of resources. To our knowledge, currently in Italy as well as in Europe, there is no CPWs codified for the management of HVA patients. This paper describes the development of the clinical content of a care pathway for the management of HVA.

METHODS

The methodology applied is based on the eight step method to build the clinical content of an evidence-based care pathway suggested by Lodewijckx et al.

RESULTS

Three hundred and seventeen different clinical activities were extracted from the selected literature. The expert panel was involved in their evaluation, expressing a judgment of relevance through the Delphi study. As a result, 126 clinical activities were appraised to be valid and feasible. The final recommendations (126) were translated into 123 key interventions. Six indicators were produced by the clinical activities.

CONCLUSION

A set of 123 key interventions and of six process indicators were found to be appropriate for the development and standardization of the clinical content of the Hymenoptera venom allergy care pathway.

Risk factors and indicators of severe systemic insect sting reactions

Hymenoptera venom allergy ranks among the top three causes of anaphylaxis worldwide, and approximately one-quarter of sting-induced reactions are classified as severe. Fatal sting reactions are exceedingly rare, but certain factors may entail a considerably higher risk. Delayed administration of epinephrine and upright posture are situational risk factors which may determine an unfavorable outcome of the acute anaphylactic episode and should be addressed during individual patient education. Systemic mastocytosis and senior age are major, unmodifiable long-term risk factors and thus reinforce the indication for venom immunotherapy. Vespid venom allergy and male sex likewise augment the risk of severe or even fatal reactions. Further studies are required to assess the impact of specific cardiovascular comorbidities. Available data regarding potential effects of beta-blockers and/or ACE inhibitors in coexisting venom allergy are inconclusive and do not justify recommendations to discontinue guideline-directed antihypertensive treatment. The absence of urticaria/angioedema during sting-induced anaphylaxis is indicative of a severe reaction, serum tryptase elevation, and mast cell clonality. Determination of basal serum tryptase levels is an established diagnostic tool for risk assessment in Hymenoptera venom-allergic patients. Measurement of platelet-activating factor acetylhydrolase activity represents a complementary approach but is not available for routine diagnostic use.

Large local reactions to Hymenoptera stings: Outcome of re-stings in real life

BACKGROUND

Large local reaction to Hymenoptera stings is usually defined as a swelling >10 cm which lasts longer than 24 hours, sometimes associated with erythema, pruritus and blisters. Currently, the risk of subsequent systemic reactions after re-stings is considered low (2%-15%). Therefore, a diagnostic workup in case of large local reaction is often judged unnecessary, as well as adrenaline auto-injector and venom immunotherapy prescription. The aim of this study was to prospectively evaluate the outcome of re-stings in a real-world setting, in patients with a history of one previous large local reaction.

METHODS

We consecutively enrolled patients who experienced their first large local reaction (as per EAACI definition), treated with antihistamine and steroids. They were followed for field re-stings and assessed for risk of subsequent systemic reactions.

RESULTS

We enrolled 662 patients. Out of the 225 re-stung subjects, 24% did not experience reactions, 52% reported a second large local reaction and 24% had systemic reactions. The risk of subsequent systemic reactions was higher in case of skin test reactivity to Apis mellifera or Vespula species (OR 2.1 and 3.8, respectively), in particular if positive at 0.001 µg/mL concentration (OR 13.4 and 16.5, respectively).

CONCLUSIONS

Systemic reactions, after a previous large local reaction, occur more frequently than that reported by literature. After analysing the predictive role of large local reactions for systemic reactions, we demonstrated that an accurate diagnostic workup may be considered, particularly skin tests. Further studies in different countries are needed to confirm these results and large local reaction management.

Hymenoptera Venom Allergy: How Does Venom Immunotherapy Prevent Anaphylaxis From Bee and Wasp Stings?

Hymenoptera stings may cause both local and systemic allergic reactions and even life threatening anaphylaxis. Along with pharmaceutical drugs and foods, hymenoptera venom is one of the most common causes of anaphylaxis in humans. To date, no parameter has been identified that may predict which sensitized people will have a future systemic sting reaction (SSR), however some risk factors, such as mastocytosis and age >40 years are known. Venom immunotherapy (VIT) is the most effective method of treatment for people who had SSR, which is shown to be effective even after discontinuation of the therapy. Development of peripheral tolerance is the main mechanism during immunotherapy. It is mediated by the production of blocking IgG/IgG4 antibodies that may inhibit IgE dependent reactions through both high affinity (FcεRI) and low affinity (FcεRII) IgE receptors on mast cells, basophils and B cells. The generation of antigen specific regulatory T cells produces IL-10 and suppresses Th2 immunity and the immune responses shift toward a Th1-type response. B regulatory cells are also involved in the production of IL-10 and the development of long term immune tolerance. During VIT the number of effector cells in target organs also decreases, such as mast cells, basophils, innate type 2 lymphocytes and eosinophils. Several meta-analyses and randomized controlled studies have proved that VIT is effective for preventing SSR to a sting and improves the quality of life. In this review, the risk of SSR in venom allergy and how VIT changed this risk are discussed.

Venom allergy treatment practices in Poland in comparison to guidelines: next edition of the national audit

INTRODUCTION

Venom immunotherapy treatment (VIT) is the only causal treatment of hymenoptera venom anaphylaxis, which aims to provide long-lasting immunoprotection against severe reactions to subsequent stings.

AIM

To reassess the compliance of VIT procedures in the Polish allergy centres with the European guidelines.

MATERIAL AND METHODS

A structured questionnaire survey conducted in all 33 VIT-centres. The response rate was 94%.

RESULTS

The ultrarush initial protocol was the most common protocol (71%, n = 22), usually lasting for 3.5 h (50%, n = 7). The most frequent (36%, n = 11) time interval from the initial to the first maintenance dose (MD) was 14 days, ranging from 7 to 35 days. All centres used an MD of 100 μg. The most frequent time interval between subsequent MDs was 4 weeks (58%, n = 18). Five years' of VIT was declared by 71% (n = 22). Before the termination of treatment, more than half of the centres (58%, n = 18) performed sIgE and almost half (42%, n = 13) performed skin tests. To confirm VIT efficacy, few centres (26%, n = 8) conducted the sting challenge. About half of centres provided the patients with an adrenalin auto-injector both at the time of initial diagnostics and at the end of treatment. More than half (55%, n = 17) used antihistamines in all patients. Almost half (45%, n = 14) declared to stop treatment with β-blockers and almost one fourth (23%, n = 7) discontinued angiotensin-converting-enzyme inhibitors.

CONCLUSIONS

In the most important procedures, there is a very high compliance with the guidelines. In the areas where the guidelines are not precise, we observed a large spread of results.

Honeybee and wasp venom allergy: Sensitization and immunotherapy

Hymenoptera venom allergy is the most common cause of anaphylactic reactions in adults. In children, it is the second most common cause after food-related anaphylaxis. Such reactions are primarily due to stings by honeybees (Apis) and certain social wasps (Vespula vulgaris and Vespula germanica in particular). Especially in adults, stings are frequently associated with severe anaphylaxis. Established diagnostic methods including molecular tests allow for greater success rates in terms of determining the insect actually responsible for triggering the anaphylactic reaction. Sensitization to both venoms, or a history of systemic sting reaction without any evidence of sensitization, complicate the decision regarding treatment. Venom immunotherapy (VIT) is a safe and effective causal treatment.

EAACI guidelines on allergen immunotherapy: Hymenoptera venom allergy

Hymenoptera venom allergy is a potentially life-threatening allergic reaction following a honeybee, vespid, or ant sting. Systemic-allergic sting reactions have been reported in up to 7.5% of adults and up to 3.4% of children. They can be mild and restricted to the skin or moderate to severe with a risk of life-threatening anaphylaxis. Patients should carry an emergency kit containing an adrenaline autoinjector, H₁ -antihistamines, and corticosteroids depending on the severity of their previous sting reaction(s). The only treatment to prevent further systemic sting reactions is venom immunotherapy. This guideline has been prepared by the European Academy of Allergy and Clinical Immunology's (EAACI) Taskforce on Venom Immunotherapy as part of the EAACI Guidelines on Allergen Immunotherapy initiative. The guideline aims to provide evidence-based recommendations for the use of venom immunotherapy, has been informed by a formal systematic review and meta-analysis and produced using the Appraisal of Guidelines for Research and Evaluation (AGREE II) approach. The process included representation from a range of stakeholders. Venom immunotherapy is indicated in venom-allergic children and adults to prevent further moderate-to-severe systemic sting reactions. Venom immunotherapy is also recommended in adults with only generalized skin reactions as it results in significant improvements in quality of life compared to carrying an adrenaline autoinjector. This guideline aims to give practical advice on performing venom immunotherapy. Key sections cover general considerations before initiating venom immunotherapy, evidence-based clinical recommendations, risk factors for adverse events and for relapse of systemic sting reaction, and a summary of gaps in the evidence.

Epinephrine in Severe Allergic Reactions: The European Anaphylaxis Register

BACKGROUND

Current guidelines recommend intramuscular administration of epinephrine as the first-line drug for the emergency treatment of severe allergic reactions (anaphylaxis), but no randomized trial evidence supports this consensus.

OBJECTIVE

We aimed to assess anaphylaxis treatment practices over 10 years, covering several European regions, all allergen sources, and all age groups.

METHODS

The European Anaphylaxis Register tracks elicitors, symptoms, emergency treatment, diagnostic workups, and long-term counseling for anaphylaxis incidents through web-based data entry from tertiary allergy specialists, covering information from the emergency respondent, patient, tertiary referral, and laboratory/clinical test results.

RESULTS

We analyzed 10,184 anaphylaxis incidents. In total, 27.1% of patients treated by a health professional received epinephrine and, in total, 10.5% received a second dose. Successful administration was less frequent in German-speaking countries (minimum 19.6%) than in Greece, France, and Spain (maximum 66.7%). Over the last decade, epinephrine administration from a health professional almost doubled to reach 30.6% in 2015-2017, half of which was applied intramuscularly. A total of 14.7% of lay- or self-treated cases were treated with an autoinjector. Of those without treatment, 22.4% carried a device for administration. No change in successful administration by lay emergency respondents was found over the last 10 years. Of the reaction and patient characteristics analyzed, only clinical severity considerably influenced the likelihood of receiving epinephrine, with 66.9% of successful administrations in near-fatal (grade IV) reactions.

CONCLUSIONS

Despite clear recommendations, only a small proportion of anaphylaxis incidents are treated with epinephrine. We demonstrated a slight increase in treated patients when handled by professionals, but stagnation in lay- or self-treated anaphylaxis. The reaction circumstances, the respondent's professional background, and patient characteristics did not explain which reactions were treated.

Venom immunotherapy and pregnancy

Introductions

The efficiency of venom immunotherapy (VIT) has been well documented by many studies. However, the most important for VIT is safety, particularly for a pregnant woman and a fetus.

Aim

To establish the influence of continuation of VIT on pregnant women and offspring.

Material and methods

The 6 women became pregnant during a specific immunotherapy. We retrospectively analyzed the influence of the immunotherapy on any complications for the pregnant women and their infants.

Results

Of the 6 patients who participated in this study, four had hyperemesis gravidarum, nausea, and heartburn, and two of them had gestational diabetes mellitus symptoms, typical of pregnancy. The observation indicated that VIT was safe for the pregnant women and their offspring.

Conclusions

The VIT is an appropriate therapeutic method for most patients with severe anaphylactic reactions after a hymenoptera sting. The observation indicated that VIT is safe for pregnant women and for their infants.

New trends in anaphylaxis

This review presents the current trends in anaphylaxis management discussed at the fourth International Network for Online-Registration of Anaphylaxis (NORA) conference held in Berlin in April 2017. Current data from the anaphylaxis registry show that Hymenoptera venom, foods, and pharmaceutical drugs are still among the most frequent triggers of anaphylaxis. Rare triggers include chicory, cardamom, asparagus, and goji berries. A meta-analysis on recent trends in insect venom anaphylaxis demonstrated for the first time that, although data on the efficacy of insect venom immunotherapy is limited, the occurrence of severe reactions upon repeated sting events can be prevented and patients' quality of life improved. Molecular diagnostics of insect venom anaphylaxis have significantly improved diagnostic sensitivity and specificity. Self-treatment of anaphylaxis is of great importance. Recent data from the anaphylaxis registry show an increase (from 23% in 2012 to 29% in 2016) in the use of adrenaline as recommended in the guidelines. A survey on the implementation of guidelines conducted among the centers reporting to the anaphylaxis registry highlights the extent to which the guideline has been perceived and implemented. Reports on a variety of cases in the anaphylaxis registry illustrate the diversity of this potentially life-threatening reaction. Component-resolved diagnostics can help to specify sensitization profiles in anaphylaxis, particularly in terms of the risk for severe reactions. Recent studies on anaphylaxis awareness show that training methods are effective; nevertheless, target groups and learning methods need to undergo further scientific investigation in coming years.

[Insect venom allergies : Update 2016 for otorhinolaryngologists]

Due to the increasing incidence of hymenoptera venom allergies and the potentially life-threatening reactions, it is important for otolaryngologists working in allergology to have an understanding of modern diagnostic and treatment standards for this allergic disease. Molecular diagnosis with recombinant single allergens from bee and wasp venom components improves the diagnostics of insect venom allergies, particularly in patients with double-positive extract-based test results. Detection of specific sensitizations to bee or wasp venom enables double sensitizations to be better distinguished from cross-reactivity. Based on patient history and test results, the patient is initially advised on avoidance strategies and prescribed an emergency medication kit. Then, the indication for allergen-specific immunotherapy (AIT) is evaluated. The dose-increase phase can be performed using conventional, cluster, rush, or ultra-rush schedules, whereby rapid desensitization (rush AIT) performed in the clinic seems to be particularly effective as initial treatment.

Allergen immunotherapy for insect venom allergy: a systematic review and meta-analysis

BACKGROUND

The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines on Allergen Immunotherapy (AIT) for the management of insect venom allergy. To inform this process, we sought to assess the effectiveness, cost-effectiveness and safety of AIT in the management of insect venom allergy.

METHODS

We undertook a systematic review, which involved searching 15 international biomedical databases for published and unpublished evidence. Studies were independently screened and critically appraised using established instruments. Data were descriptively summarized and, where possible, meta-analysed.

RESULTS

Our searches identified a total of 16 950 potentially eligible studies; of which, 17 satisfied our inclusion criteria. The available evidence was limited both in volume and in quality, but suggested that venom immunotherapy (VIT) could substantially reduce the risk of subsequent severe systemic sting reactions (OR = 0.08, 95% CI 0.03-0.26); meta-analysis showed that it also improved disease-specific quality of life (risk difference = 1.41, 95% CI 1.04-1.79). Adverse effects were experienced in both the build-up and maintenance phases, but most were mild with no fatalities being reported. The very limited evidence found on modelling cost-effectiveness suggested that VIT was likely to be cost-effective in those at high risk of repeated systemic sting reactions and/or impaired quality of life.

CONCLUSIONS

The limited available evidence suggested that VIT is effective in reducing severe subsequent systemic sting reactions and in improving disease-specific quality of life. VIT proved to be safe and no fatalities were recorded in the studies included in this review. The cost-effectiveness of VIT needs to be established.