Current Pharmaceutical Design - Volume 29, Issue 3, 2023

Hymenoptera stings can induce allergic and occasionally fatal reactions, and are responsible for significant morbidity and deterioration in health-related quality of life. The diagnostic work-up must consider the medical history of patients, in the context of venom allergy epidemiology and Hymenoptera taxonomy, and the clinical manifestations of the reactions, to channel the available in vivo and in vitro tests towards the most accurate diagnosis and the consequent appropriate management, also considering the risk profile of the patients on a precision-medicine approach. All these aspects are covered by this work that aims at providing an up-to-date review to increase the awareness of this topic among interested stakeholders, like healthcare professionals and political decision makers, who can contribute to the proper immediate and long-term management of venom allergy and anaphylaxis.

Immediate hypersensitivity reactions can pose a clinical and diagnostic challenge, mainly because of the multifarious clinical presentation and distinct underlying - frequently uncertain - mechanisms. Anaphylaxis encompasses all rapidly developing and life-threatening signs and may cause death. Evidence has accumulated that immediate hypersensitivity and anaphylaxis do not necessarily involve an allergen-specific immune response with cross-linking of specific IgE (sIgE) antibodies bound to their high-affinity IgE receptor (FcεRI) on the surface of mast cells (MCs) and basophils. Immediate hypersensitivity and anaphylaxis can also result from alternative specific and nonspecific MC and basophils activation and degranulation, such as complementderived anaphylatoxins and off-target occupancy of MC and/or basophil surface receptors such as the Masrelated G protein-coupled receptor X2 (MRGPRX2). Degranulation of MCs and basophils results in the release of inflammatory mediators, which can be, depending on the underlying trigger, in a different spatiotemporal manner. In addition, hypersensitivity and anaphylaxis can occur entirely independently of MC and basophil degranulation, as observed in hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) that divert normal arachidonic acid metabolism by inhibiting the cyclooxygenase (COX)-1 isoenzyme. Finally, one should remember that anaphylaxis might be part of the phenotype of particular - sometimes poorly recognizable - conditions such as clonal MC diseases (e.g. mastocytosis) and MC activation syndrome. This review provides a status update on the molecular mechanisms involved in both sIgE/FcεRI- and non-sIgE/FcεRI-dependent immediate hypersensitivity and anaphylaxis. In conclusion, there is increasing evidence for alternative pathophysiological hypersensitivity and anaphylaxis endotypes that are phenotypically and biologically indistinguishable, which are frequently difficult to diagnose, mainly because of uncertainties associated with diagnostic tests that might not enable to unveil the underlying mechanism.

Anaphylaxis is defined as a severe life-threatening, generalized or systemic hypersensitivity reaction. Yet, anaphylaxis is often difficult to diagnose, leading to a delay in applying appropriate management. Epinephrine is the medication of choice for the immediate treatment of anaphylaxis. The rest of the actions to be taken during the acute anaphylaxis episode, including administering other medications, will depend on the response to epinephrine. Epinephrine auto-injectors (EAI) are the preferred method for administering the treatment of anaphylaxis in the community setting. However, there are multiple potential barriers to using epinephrine during an anaphylactic reaction related to the physicians and the patients themselves. Strategies to overcome gaps in the acute management of anaphylaxis include novel injection devices and research of new routes for epinephrine delivery. Electronic health solutions may also have a role at this level. Long-term management of anaphylaxis is focused on the prevention of new episodes. Etiologic diagnosis and patient education are key to this end. The application of health information technologies, such as telemedicine, social media, and mobile health, can be helpful for the long-term management of anaphylaxis. Additionally, some patients may benefit from long-term immunomodulatory and etiologic treatments when allergen avoidance implies negative consequences. This review article addresses the most recent advances regarding the integral management of anaphylaxis, including pharmacological and non-pharmacological measures.

Drug hypersensitivity is increasing worldwide as the consumption of drug is increasing. Many clinical presentations of drug hypersensitivity are complex and take place in the setting of illness and/or polypharmacotherapy. To review the most recent findings in the diagnosis and management of immediate drug hypersensitivity reactions. Studies were selected based on their relevance, originality and date of publication. The understanding of endotypes, biomarkers and phenotypes has improved the categorization of immediate hypersensitivity reactions. In this review, we discussed the short- and long-term management of anaphylaxis with a special focus on in vivo and in vitro diagnostic methods. Moreover, the clinical management of drug-induced anaphylaxis, the role of hidden allergens and the importance of delabeling are discussed. Endophenotyping is crucial to correctly diagnose and treat patients with immediate drug hypersensitivity reactions, preventing future episodes through drug desensitization.

Although an increase in the incidence of childhood anaphylaxis has been reported, it remains underdiagnosed. Foods are the most common triggers for anaphylaxis, particularly cow's milk, hen's egg, and nuts. Other common causes of anaphylaxis in children and adolescents include venom and drugs. The skin is the most commonly affected organ, but approximately 10% of patients with anaphylaxis may present without skin symptoms, which can lead to misdiagnosis. Recognition of anaphylaxis is a great challenge in children, possibly due to a lack of vigilance among patients, caregivers, and healthcare professionals, but also in part due to discrepancies in the clinical definition of anaphylaxis. In addition, anaphylaxis in infants often poses a distinct challenge because the wide spectrum of clinical manifestations and the inability of infants to describe their symptoms may hinder prompt diagnosis and treatment. Given the rapid onset of anaphylaxis and its unpredictable severity, rapid assessment and appropriate treatment are critical. Although the morbidity and mortality associated with anaphylaxis are potentially preventable with the timely administration of life-saving epinephrine, anaphylaxis is still undertreated worldwide. Long-term management of pediatric anaphylaxis is a patientcentered, multidimensional approach that focuses on the recognition of anaphylaxis, the use of epinephrine auto- injectors, and prevention of recurrences. Therefore, close communication and collaboration between the child, caregivers, healthcare professionals, and schools are the cornerstone of long-term care. This paper is designed to provide a comprehensive overview of current perspectives and concepts related to anaphylaxis in the pediatric population in light of recent guidelines and literature.

Anaphylaxis should be clinically diagnosed with immediate recognition, whereas, despite advances in the field of allergy, the symptoms of anaphylaxis remain to be under-recognized, diagnosis is often missed, and treatment is often delayed. Anaphylaxis presents with symptoms in a spectrum of severity, ranging from mild objective breathing problems to circulatory shock and/or collapse. Indeed, anaphylaxis management frequently relies on a ‘one-size-fits-all approach’ rather than a precision medicine care model, despite the evidence that anaphylaxis is a heterogeneous condition with differences in causative agents, clinical presentation, and host susceptibility. The key important risk factors for severe anaphylaxis and mortality are certain age groups or certain stages of life (infants, elderly and pregnant women), augmenting factors (physical exercise, alcohol consumption, menstruation, acute infections), concurrent use of some medications (beta-adrenergic blockers (β-blockers) and angiotensin-converting enzyme (ACE) inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), and proton pump inhibitors (PPIs), and concomitant diseases (i.e. asthma, cardiovascular disease, mastocytosis). The present review aims to collectively address the patient groups who are at high risk of having anaphylaxis, those who have a more severe course, those that are difficult to diagnose, and require a special approach in treatment. Therefore, the risky populations like the elderly, pregnant women, patients receiving β- blockers or ACE inhibitors, those with concomitant cardiovascular diseases, asthma, and mastocytosis, or those having higher baseline serum tryptase levels are discussed, including their clinical presentations and treatment strategies. Additionally, anaphylaxis during the perioperative period is addressed.