Drug hypersensitivity, in vitro tools, biomarkers, and burden with COVID-19 vaccines.

Hypersensitivity reactions to drugs are increasing worldwide. They display a large degree of variability in the immunological mechanisms involved, which impacts both disease severity and the optimal diagnostic procedure. Therefore, drug hypersensitivity diagnosis relies on both in vitro and in vivo assessments, although most of the methods are not well standardized. Moreover, several biomarkers can be used as valuable parameters for precision medicine that provide information on the endotypes, diagnosis, prognosis, and prediction of drug hypersensitivity development, as well on the identification of therapeutic targets and treatment efficacy monitoring. Furthermore, in the last 2 years, the SARS-CoV-2 (severe acute respiratory syndrome-coronavirus) pandemic has had an important impact on health system, leading us to update approaches on how to manage hypersensitivity reactions to drugs used for its treatment and on COVID-19 (Coronavirus disease) vaccines used for its prevention. This article reviews recent advances in these 3 areas regarding drug hypersensitivity: in vitro tools for drug hypersensitivity diagnosis, recently identified biomarkers that could guide clinical decision making and management of hypersensitivity reactions to drugs and vaccines used for COVID-19.

Telemedicine in Drug Hypersensitivity.

This review focuses on the current applications of telemedicine for drug hypersensitivity reactions. Telemedicine holds promise as a tool to risk-stratify patients with drug hypersensitivity, for both evaluation of penicillin allergies and severe cutaneous adverse reactions. Although telemedicine may not fully replace in-person assessment owing to the need for testing, challenges, and in-person physical examination or skin biopsy, it may allow for risk stratification whereby some in-person visits may not be necessary. Electronic consults have also emerged along with telemedicine as a tool for drug allergy evaluations.

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.

Practical management of suspected hypersensitivity reactions to anti-tuberculosis drugs.

Tuberculosis (TB) is the commonest cause of death by a single infectious agent globally and ranks amongst the top ten causes of global mortality. The incidence of TB is highest in Low-Middle Income countries (LMICs). Prompt institution of, and compliance with, therapy are cornerstones for a favourable outcome in TB and to mitigate the risk of multiple drug resistant (MDR)-TB, which is challenging to treat. There is some evidence that adverse drug reactions (ADRs) and hypersensitivity reactions (HSRs) to anti-TB drugs occur in over 60% and 3%-4% of patients respectively. Both ADRs and HSRs represent significant barriers to treatment adherence and are recognised risk factors for MDR-TB. HSRs to anti-TB drugs are usually cutaneous and benign, occur within few weeks after commencement of therapy and are likely to be T-cell mediated. Severe and systemic T-cell mediated HSRs and IgE mediated anaphylaxis to anti-TB drugs are relatively rare, but important to recognise and treat promptly. T-cell-mediated HSRs are more frequent amongst patients with co-existing HIV infection. Some patients develop multiple sensitisation to anti-TB drugs. Whilst skin tests, patch tests and in vitro diagnostics have been used in the investigation of HSRs to anti-TB drugs, their predictive value is not established, they are onerous, require specialist input of an allergist and are resource-dependent. This is compounded by the global, unmet demand for allergy specialists, particularly in low-income countries (LICs)/LMICs and now the challenging circumstances of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. This narrative review provides a critical analysis of the limited published evidence on this topic and proposes a cautious and pragmatic approach to optimise and standardise the management of HSRs to anti-TB drugs. This includes clinical risk stratification and a dual strategy involving sequential re-challenge and rapid drug desensitisation. Furthermore, a concerted international effort is needed to generate real-time data on ADRs, HSRs, safety and clinical outcomes of these interventions.

Allergic reactions against Covid-19 vaccines

Coronavirus Disease 2019 (COVID-19) affected the whole world in a short time. One of the most influential public health initiatives modern medicine has to offer, the vaccine has become even more important as the COVID-19 pandemic continues to worsen worldwide. Many vaccine trials were launched during the COVID-19 pandemic, and these vaccines were widely used around the world, offering realistic hope for ending the pandemic. Allergic reactions to vaccines were reported shortly after their approval. These reactions, in general, are rare, but, in some circumstances, they can be serious. Allergy to vaccines can occur because of either the active vaccine component or vaccine ingredients. The spectrum of the reactions may be just a local hypersensitiviy reaction or may be as severe as an anaphylaxis, which is an acute severe, life-threatening systemic hypersensitive reaction, and it requires quick intervention. If an allergy is suspected, a correct examination followed by algorithms is important for true diagnosis, treatment, and decision regarding revaccination. Patients who experience an allergic reaction with the first dose of covid 19 vaccine should be directed to the allergy-immunologist, and the evaluation of at-risk patients should be individualized. Finally, we should point out that the benefits of current COVID-19 vaccines go far beyond the side effects, and that the vaccine is the most important way to recover from the pandemic.

Drug allergy management in the elderly.

PURPOSE OF REVIEW: Drug allergy management has previously not been emphasized in the elderly. However, the geriatric population poses several unique characteristics, challenges for drug allergy testing and considerations in the management. Especially in the era of COVID-19, the elderly population is a vulnerable cohort and reviewing the management during this unprecedented time is both timely and relevant. RECENT FINDINGS: In recent years, larger scale studies focusing on the epidemiology and prevalence trends of drug allergies among older adults has been summarized in this review. Emphasis on anaphylaxis in the older adults has been studied. SUMMARY: There are many implications of these findings. Epidemiological studies are useful in realizing the burden and spectrum of drug allergies on our healthcare system. It has allowed us to identify certain barriers in drug allergy management and develop ways to overcome these challenges through. Lastly, we have proposed an approach to drug allergy management based on previous studies as well as from our perspective and local experience.

Adverse reactions to COVID-19 vaccines: A practical approach.

COVID-19-related mortality in high-risk individuals is substantial and current treatment options are limited. There is convincing evidence that the COVID-19 vaccines reduce the severity of infection and prevent deaths. Three COVID-19 vaccines are approved in the United Kingdom with many more in development. There are limited data on the triggers and mechanisms of anaphylaxis to these vaccines. We review the potential allergenic compounds in the COVID-19 vaccines and describe an innovative allergy support model for the vaccination hubs that allows most patients with severe allergy be immunized. Finally, we propose a practical algorithm for the investigations of anaphylaxis to these vaccines.

Management of Allergic Diseases During COVID-19 Outbreak.

PURPOSE OF REVIEW: The coronavirus disease 2019 (COVID-19) has challenged healthcare system capacities and safety for health care workers, reshaping doctor-patient interaction favoring e-Health or telemedicine. The pandemic situation may make difficult to prioritize patients with allergies diseases (AD), face-to-face evaluation, and moreover concern about the possible COVID-19 diagnosis, since COVID-19 shared many symptoms in common with AD. Being COVID-19 a novel disease, everyone is susceptible; there are some advances on vaccine and specific treatment. We evaluate existing literature on allergic diseases (AD): allergic rhinitis, asthma, food allergy, drug allergy, and skin allergy, and potential underlying mechanisms for any interrelationship between AD and COVID-19. RECENT FINDINGS: There is inconclusive and controversial evidence of the association between AD and the risk of adverse clinical outcomes of COVID-19. AD patients should minimize hospital and face-to-face visits, and those who have used biologics and allergen immunotherapy should continue the treatment. It is essential to wear personal protective equipment for the protection of health care workers. Social distancing, rational use of facemasks, eye protection, and hand disinfection for health care workers and patients deserve further attention and promotion. Teleconsultation during COVID-19 times for AD patients is very encouraging and telemedicine platform can provide a reliable service in patient care.