Hypersensitivity reactions to proton pump inhibitors. An EAACI position paper.

Proton pump inhibitors (PPIs) are invaluable therapeutic options in a variety of dyspeptic diseases. In addition to their well-known risk profile, PPI consumption is related to food and environmental allergies, dysbiosis, osteoporosis, as well as immediate and delayed hypersensitivity reactions (HSRs). The latter, although a rare event, around 1%-3%, due to the extraordinarily high rate of prescription and consumption of PPIs are related to a substantial risk. In this Position Paper, we provide clinicians with practical evidence-based recommendations for the diagnosis and management of HSRs to PPIs. Furthermore, the unmet needs proposed in the document aim to stimulate more in-depth investigations in the topic.

Allergies and COVID-19 vaccines: An ENDA/EAACI Position paper.

BACKGROUND: Anaphylaxis, which is rare, has been reported after COVID-19 vaccination, but its management is not standardized. METHOD: Members of the European Network for Drug Allergy and the European Academy of Allergy and Clinical Immunology interested in drug allergy participated in an online questionnaire on pre-vaccination screening and management of allergic reactions to COVID-19 vaccines, and literature was analysed. RESULTS: No death due to anaphylaxis to COVID-19 vaccines has been confirmed in scientific literature. Potential allergens, polyethylene glycol (PEG), polysorbate and tromethamine are excipients. The authors propose allergy evaluation of persons with the following histories: 1-anaphylaxis to injectable drug or vaccine containing PEG or derivatives; 2-anaphylaxis to oral/topical PEG containing products; 3-recurrent anaphylaxis of unknown cause; 4-suspected or confirmed allergy to any mRNA vaccine; and 5-confirmed allergy to PEG or derivatives. We recommend a prick-to-prick skin test with the left-over solution in the suspected vaccine vial to avoid waste. Prick test panel should include PEG 4000 or 3500, PEG 2000 and polysorbate 80. The value of in vitro test is arguable. CONCLUSIONS: These recommendations will lead to a better knowledge of the management and mechanisms involved in anaphylaxis to COVID-19 vaccines and enable more people with history of allergy to be vaccinated.

Dangerous liaisons: Bacteria, antimicrobial therapies, and allergic diseases.

Microbiota composition and associated metabolic activities are essential for the education and development of a healthy immune system. Microbial dysbiosis, caused by risk factors such as diet, birth mode, or early infant antimicrobial therapy, is associated with the inception of allergic diseases. In turn, allergic diseases increase the risk for irrational use of antimicrobial therapy. Microbial therapies, such as probiotics, have been studied in the prevention and treatment of allergic diseases, but evidence remains limited due to studies with high heterogeneity, strain-dependent effectiveness, and variable outcome measures. In this review, we sketch the relation of microbiota with allergic diseases, the overuse and rationale for the use of antimicrobial agents in allergic diseases, and current knowledge concerning the use of bacterial products in allergic diseases. We urgently recommend 1) limiting antibiotic therapy in pregnancy and early childhood as a method contributing to the reduction of the allergy epidemic in children and 2) restricting antibiotic therapy in exacerbations and chronic treatment of allergic diseases, mainly concerning asthma and atopic dermatitis. Future research should be aimed at antibiotic stewardship implementation strategies and biomarker-guided therapy, discerning those patients that might benefit from antibiotic therapy.

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.

What is new in beta-lactam allergy in children?

This review highlights the novelties in understanding the underlying immunologic mechanisms of drug hypersensitivity reactions (DHRs) with special reference to beta-lactams (BLs) in the pediatric population, as well as tiny changes in clinical classification and diagnosis of DHRs, in the last couple of years. BLs are still the most commonly prescribed and used antibiotics in children. Viral infections are very often in children, and they can provoke skin rashes which are difficult to differentiate from DHRs. The majority of children are incorrectly labeled as "allergic." Therefore, allergy to BLs in children is overdiagnosed. These children often receive suboptimal treatment with second-line broad-spectrum antibiotics, which are less effective, more costly, and associated with an increased risk of antibiotic-resistant infections. This prolongs hospitalization and thus more uses health care. The correct diagnosis of BL allergy in children is still an important and hot topic. This review has outlined the need for correct diagnosis of BL allergy in children and all the controversies encountered by pediatricians and pediatric allergists. It is also necessary to change the paradigm.

Skin eruptions in children: Drug hypersensitivity vs viral exanthema.

Childhood rashes or exanthemas are common and are usually relatively benign. There are many causes of rash in children, including mainly viruses, and less often bacterial toxins, drugs, allergens and other diseases. Viral exanthema often appears while children are taking a medication in the course of a viral infection; it can mimic drug exanthema and is perceived as a drug allergy in 10% of cases. In the vast majority of cases, the distinction between virus-induced and drug-induced skin eruption during the acute phase is not possible. The drugs most commonly implicated are beta-lactams (BL) and non-steroidal anti-inflammatory drugs (NSAIDs). Viruses, commonly Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6) and cytomegalovirus (CMV), and the bacterium, Mycoplasma pneumoniae, may cause exanthema either from the infection itself (active or latent) or because of interaction with drugs that are taken simultaneously. Determination of the exact diagnosis requires a careful clinical history and thorough physical examination. Haematological and biochemical investigations and histology are not always helpful in differentiating between the two types of exanthema. Serological and polymerase chain reaction (PCR) assays can be helpful, although a concomitant acute infection does not exclude drug hypersensitivity. A drug provocation test (DPT) is although considered the gold standard for the diagnosis and is not preferred by the patients. Skin tests are not well tolerated, and in vitro tests, such as the basophil activation test and lymphocyte transformation, are of low sensitivity and specificity and their relevance is debatable. Based on current evidence, we propose a systematic clinical approach for timely differential diagnosis and management of rashes in children who present a cutaneous eruption while receiving a drug.

An EAACI Task Force report on allergy to beta-lactams in children: Clinical entities and diagnostic procedures.

Beta-lactam (BL) allergy suspicion is common in children and constitutes a major public health problem, with an impact on patient's health and on medical costs. However, it has been found that most of these reactions are not confirmed by a complete allergic workup. The diagnostic value of the currently available allergy tests has been investigated intensively recently by different groups throughout the world. This has led to major changes in the management of children with a suspected BL allergy. Particularly, it is now well accepted that skin tests can be skipped before the drug provocation test in children with a benign non-immediate reaction to BL. However, there is still a debate on the optimal allergic workup to perform in children with a benign immediate reaction. In addition, management of children with severe cutaneous adverse drug reactions remains difficult. In this review, based on a selection of the most relevant studies found in the literature, we will review and discuss the diagnosis of different forms of BL allergy in children.

Delayed hypersensitivity to antiepileptic drugs in children.

BACKGROUND: Antiepileptic drugs (AEDs) are widely used for the treatment of epilepsy, but they can be associated with the development of mainly delayed/non-immediate hypersensitivity reactions (HRs). Although these reactions are usually cutaneous, self-limited, and spontaneously resolve within days after drug discontinuation, sometime HR reactions to AEDs can be severe and life-threatening. AIM: This paper seeks to show examples on practical management of AED HRs in children starting from a review of what it is already known in literature. RESULTS: Risk factors include age, history of previous AEDs reactions, viral infections, concomitant medications, and genetic factors. The diagnostic workup consists of in vivo (intradermal testing and patch testing) and in vitro tests [serological investigation to exclude the role of viral infection, lymphocyte transformation test (LTT), cytokine detection in ELISpot assays, and granulysin (Grl) in flow cytometry. Treatment is based on a prompt drug discontinuation and mainly on the use of glucocorticoids. CONCLUSION: Dealing with AED HRs is challenging. The primary goal in the diagnosis and management of HRs to AEDs should be trying to accurately identify the causal trigger and simultaneously identify a safe and effective alternative anticonvulsant. There is therefore an ongoing need to improve our knowledge of HS reactions due to AED medications and in particular to improve our diagnostic capabilities.

Diagnosis and management of the drug hypersensitivity reactions in Coronavirus disease 19: An EAACI Position Paper.

Coronavirus disease 2019 (COVID-19), a respiratory tract infection caused by a novel human coronavirus, the severe acute respiratory syndrome coronavirus 2, leads to a wide spectrum of clinical manifestations ranging from asymptomatic cases to patients with mild and severe symptoms, with or without pneumonia. Given the huge influence caused by the overwhelming COVID-19 pandemic affecting over three million people worldwide, a wide spectrum of drugs is considered for the treatment in the concept of repurposing and off-label use. There is no knowledge about the diagnosis and clinical management of the drug hypersensitivity reactions that can potentially occur during the disease. This review brings together all the published information about the diagnosis and management of drug hypersensitivity reactions due to current and candidate off-label drugs and highlights relevant recommendations. Furthermore, it gathers all the dermatologic manifestations reported during the disease for guiding the clinicians to establish a better differential diagnosis of drug hypersensitivity reactions in the course of the disease.

Towards a more precise diagnosis of hypersensitivity to beta-lactams - an EAACI position paper.

A recent survey of the European Academy of Allergy and Clinical Immunology (EAACI) Drug Allergy Interest Group (DAIG) on how European allergy specialists deal with beta-lactam (BL) hypersensitivity demonstrated a significant heterogeneity in current practice, suggesting the need to review and update existing EAACI guidelines in order to make the diagnostic procedures as safe and accurate, but also as cost-effective, as possible. For this purpose, a bibliographic search on large studies regarding BL hypersensitivity diagnosis was performed by an EAACI task force, which reviewed and evaluated the literature data using the GRADE system for quality of evidence and strength of recommendation. The updated guidelines provide a risk stratification in BL hypersensitivity according to index reaction(s), as well as an algorithmic approach, based on cross-reactivity studies, in patients with a suspicion of BL hypersensitivity and an immediate need for antibiotic therapy, when referral to an allergist is not feasible. Furthermore, the update addresses availability and concentrations of skin test (ST) reagents, ST and drug provocation test (DPT) protocols, and diagnostic algorithms and administration of alternative BL in allergic subjects. Specifically, distinct diagnostic algorithms are suggested depending on risk stratification of the patient into high and low risk based on the morphology and chronology of the reaction, immediate (ie, occurring within 1-6 hours after the last administered dose) or nonimmediate (ie, occurring more than 1 hour after the initial drug administration), and the reaction severity. Regarding the allergy workup, the main novelty of this document is the fact that in some low-risk nonimmediate reactions ST are not mandatory, especially in children. For DPT, further studies are necessary to provide data supporting the standardization of protocols, especially of those regarding nonimmediate reactions, for which there is currently no consensus.

Genetic variants associated with T cell-mediated cutaneous adverse drug reactions: A PRISMA-compliant systematic review-An EAACI position paper.

Drug hypersensitivity reactions (DHRs) are associated with high global morbidity and mortality. Cutaneous T cell-mediated reactions classically occur more than 6 hours after drug administration and include life-threatening conditions such as toxic epidermal necrolysis, Stevens-Johnson syndrome, and hypersensitivity syndrome. Over the last 20 years, significant advances have been made in our understanding of the pathogenesis of DHRs with the identification of human leukocyte antigens as predisposing factors. This has led to the development of pharmacogenetic screening tests, such as HLA-B*57:01 in abacavir therapy, which has successfully reduced the incidence of abacavir hypersensitivity reactions. We have completed a PRISMA-compliant systematic review to identify genetic associations that have been reported in DHRs. In total, 105 studies (5554 cases and 123 548 controls) have been included in the review reporting genetic associations with carbamazepine (n = 31), other aromatic antiepileptic drugs (n = 24), abacavir (n = 11), nevirapine (n = 14), trimethoprim-sulfamethoxazole (n = 11), dapsone (n = 4), allopurinol (n = 10), and other drugs (n = 5). The most commonly reported genetic variants associated with DHRs are located in human leukocyte antigen genes and genes involved in drug metabolism pathways. Increasing our understanding of genetic variants that contribute to DHRs will allow us to improve diagnosis, develop new treatments, and predict and prevent DHRs in the future.

The role of mobile health technologies in allergy care: An EAACI position paper.

Mobile health (mHealth) uses mobile communication devices such as smartphones and tablet computers to support and improve health-related services, data and information flow, patient self-management, surveillance, and disease management from the moment of first diagnosis to an optimized treatment. The European Academy of Allergy and Clinical Immunology created a task force to assess the state of the art and future potential of mHealth in allergology. The task force endorsed the "Be He@lthy, Be Mobile" WHO initiative and debated the quality, usability, efficiency, advantages, limitations, and risks of mobile solutions for allergic diseases. The results are summarized in this position paper, analyzing also the regulatory background with regard to the "General Data Protection Regulation" and Medical Directives of the European Community. The task force assessed the design, user engagement, content, potential of inducing behavioral change, credibility/accountability, and privacy policies of mHealth products. The perspectives of healthcare professionals and allergic patients are discussed, underlining the need of thorough investigation for an effective design of mHealth technologies as auxiliary tools to improve quality of care. Within the context of precision medicine, these could facilitate the change in perspective from clinician- to patient-centered care. The current and future potential of mHealth is then examined for specific areas of allergology, including allergic rhinitis, aerobiology, allergen immunotherapy, asthma, dermatological diseases, food allergies, anaphylaxis, insect venom, and drug allergy. The impact of mobile technologies and associated big data sets are outlined. Facts and recommendations for future mHealth initiatives within EAACI are listed.

Controversies in drug allergy: In vitro testing.

Despite their low frequency, drug hypersensitivity reactions (DHRs) can be serious and result in lifelong sequelae. The diagnosis is critical to avert future reactions and should identify the culprit drug or drugs and safe alternatives. However, making the diagnosis can be complex and challenging. Reliable in vitro tests can offer the potential to improve a diagnosis of DHR and influence medical decision making. Importantly, in vitro testing is frequently not performed as a test in isolation but rather as a component of a diagnostic algorithm along with additional tests. There are several in vitro approaches for the different endotypes of DHRs. However, only few are available for routine diagnosis, and many are restricted to research laboratories. In vitro tests exhibit varying sensitivity and specificity depending on the drug involved and the clinical phenotype. In vitro tests can complement skin tests, especially in patients with negative or equivocal skin test responses inconsistent with the clinical presentation and in severe reactions in which drug provocation tests are contraindicated. The main unmet need for many in vitro tests for the diagnosis of DHRs is validation in larger studies with standardized controls that could harmonize diagnostic management between the United States, European Union, and other regions of the world.

A EAACI drug allergy interest group survey on how European allergy specialists deal with ß-lactam allergy.

An accurate diagnosis of ß-lactam (BL) allergy can reduce patient morbidity and mortality. Our aim was to investigate the availability of BL reagents, their use and test procedures in different parts of Europe, as well as any differences in the diagnostic workups for evaluating subjects with BL hypersensitivity. A survey was emailed to all members of the EAACI Drug Allergy Interest Group (DAIG) between February and April 2016, and the questionnaire was meant to study the management of suspected BL hypersensitivity. The questionnaire was emailed to 82 DAIG centres and answered by 57. Amoxicillin alone or combined to clavulanic acid were the most commonly involved BL except in the Danish centre, where penicillin V was the most frequently suspected BL. All centres performed an allergy workup in subjects with histories of hypersensitivity to BL: 53 centres (93%) followed DAIG guidelines, two national guidelines and two local guidelines. However, there were deviations from DAIG recommendations concerning allergy tests, especially drug provocation tests. A significant heterogeneity exists in current practice not only among countries, but also among centres within the same country. This suggests the need to re-evaluate, update and standardize protocols on the management of patients with suspected BL allergy.

Hypersensitivity reactions to antiepileptic drugs in children.

BACKGROUND: Antiepileptic drugs (AEDs) can cause hypersensitivity reactions in children. These reactions are mainly cutaneous, self-limiting, and benign, but life-threatening severe cutaneous adverse reactions can occur. Infections can lead to skin eruptions and mimic drug hypersensitivity reactions, if a drug is taken at the same time. The aims of our study were to confirm or rule out the diagnosis of hypersensitivity reactions to AEDs in children and to detect an infection which mimics these reactions. METHODS: A prospective survey was conducted in a group of 100 children with histories of hypersensitivity reactions to AEDs by performing patch tests, delayed-reading intradermal test, and, in case of negative results, challenge test. In all children, a study was performed to detect infections by viruses or Mycoplasma pneumoniae. RESULTS: Maculopapular exanthema and delayed-appearing urticaria were the most reported hypersensitivity reactions to AEDs. Sixty-six (66%) of 100 children had confirmed hypersensitivity reactions to AEDs. Fifty-nine children had positive patch test. No children had positive challenge tests. The most common AEDs causing hypersensitivity reactions were carbamazepine (45.4%) and lamotrigine (43.6%). Thirty-two children had positive tests for viruses or M pneumoniae, and nine of them had also a positive allergy work-up. CONCLUSION: Considering that there are no specific tests to distinguish between a viral infection and hypersensitivity reactions to AEDs in the acute phase, a diagnostic work-up should be performed in all children with suspected hypersensitivity reactions to AEDs, as well as infectious agent study, to remove a false label of hypersensitivity.

Diagnosis and management of drug-induced anaphylaxis in children: An EAACI position paper.

Drug hypersensitivity reactions (DHR) constitute a major and common public health problem, particularly in children. One of the most severe manifestations of DHR is anaphylaxis, which might be associated with a life-threatening risk. During those past decades, anaphylaxis has received particularly a lot of attention and international consensus guidelines have been recently published. Whilst drug-induced anaphylaxis is more commonly reported in adulthood, less is known about the role of drugs in pediatric anaphylaxis. Betalactam antibiotics and non-steroidal anti-inflammatory drugs are the most commonly involved drugs, probably related to high prescription rates. Diagnosis relies on the recognition of symptoms pattern and is based on complete allergic workup, particularly including skin tests and/or specific IgE. However, the real diagnostic value of those tests to diagnose immediate reactions in children remains not well defined for a significant number of the drugs. Generally, a drug provocation test is discussed to confirm or exclude an immediate-onset drug-induced hypersensitivity. Although avoidance of the incriminated drug (and related drug) is the rule, rapid desensitization is useful in selected subgroups of patients. There is a need for large, multicentric studies, to evaluate the real diagnostic value of the currently available skin tests. Moreover there is also a need to develop new diagnostic tests in the future to improve the management of these children.

Diagnosis of Eosinophilic Esophagitis in Children: A Serbian Single-Center Experience from 2010 to 2017.

OBJECTIVES: The aim of this study was to assess the epidemiological, clinical, endoscopic, and pathohistological characteristics of pediatric eosinophilic esophagitis (EoE) in Serbia. METHOD: All children aged 0-18 years diagnosed with EoE in the period between 2010 and 2017 at the University Children's Hospital in Belgrade, Serbia, were retrospectively enrolled. RESULTS: EoE was diagnosed in 35 children (12.45 ± 3.77 years) with a male predominance (74%). The median incidence rate was estimated to be 0.85 per 100,000 children per year with the highest rate estimated at 3.17 per 100,000 children in 2017. Dysphagia (71.4%) and food impaction (40%) were dominant symptoms. Inflammatory endoscopic changes were found in 74.3% and fibrostenotic changes in 62.9% of the children. The esophageal biopsy rate was low (6.8%), especially in children with reflux and nonspecific symptoms. Subepithelial fibrosis was found in only 20% of the patients. Since 2016, the number of biopsy samples has increased, but the sampling rate of lamina propria is still low (<50%). The correlation between the number of biopsies and lamina propria acquisition was strong (rs = 0.773, p < 0.05). In 2 immunocompetent adolescents, EoE was diagnosed after successful treatment of infectious esophagitis. CONCLUSIONS: An increase in the incidence of EoE in Serbian children is evident. The biopsy rate in children with nonspecific and reflux symptoms should be increased, as well as the number of biopsy samples for the detection of subepithelial fibrosis. In immunocompetent children with infectious esophagitis, EoE should be suspected and endoscopy may be recommended after successful treatment of infection.

EAACI/ENDA Position Paper: Diagnosis and management of hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) in children and adolescents.

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in the pediatric population as antipyretics/analgesics and anti-inflammatory medications. Hypersensitivity (HS) reactions to NSAID in this age group, while similar to adults, have unique diagnostic and management issues. Although slowly accumulating, published data in this age group are still relatively rare and lacking a unifying consensus. This work is a summary of current knowledge and consensus recommendations utilizing both published data and expert opinion from the European Network of Drug Allergy (ENDA) and the Drug Hypersensitivity interest group in the European Academy of Allergy and Clinical Immunology (EAACI). This position paper summarizes diagnostic and management guidelines for children and adolescents with NSAIDs hypersensitivity.