Steroid Allergy: Clinical Features and the Importance of Excipient Testing in a Diagnostic Algorithm

Polyethylene glycol hypersensitivity, patient outcomes in a 7-year retrospective study

BACKGROUND

Immediate IgE-mediated hypersensitivity reactions to polyethylene glycol (PEG) are rare. Our understanding of PEG hypersensitivity is limited.

OBJECTIVE

To evaluate the clinical characteristics and investigation outcomes of the largest cohort of patients with PEG allergy reported.

METHODS

A total of 44 patients investigated for suspected PEG allergy across 4 United Kingdom tertiary allergy centers between October 2013 and December 2020 were studied. Clinical characteristics, index reaction, and approaches to and outcomes of allergy investigations were analyzed.

RESULTS

PEG hypersensitivity was confirmed in 42 of 44 cases. Macrogol laxatives were the most common index drugs reported (23%), followed by depo-medroxyprogesterone (19%), oral penicillin V (10%), and depo-methylprednisolone (10%). In general, 61% experienced grade III anaphylaxis. Intradermal testing (IDT) increased the diagnostic sensitivity from 51% to 85%. Five patients experienced systemic reactions during IDT. Of the 5 patients, 2 were skin prick test positive to a high molecular weight PEG. Three patients with negative skin test results had positive drug provocation test results. Seven patients with PEG allergy reported tolerance to H1-antihistamines containing PEG. Administration of messenger RNA COVID-19 or Oxford/AstraZeneca COVID-19 vaccines was tolerated in all 16 patients to whom they were administered.

CONCLUSION

PEG hypersensitivity is an uncommon cause of drug-induced anaphylaxis. Four index drugs accounted for two-thirds of the cases, and reactions to these drugs should prompt PEG hypersensitivity investigations. PEG IDT increases diagnostic yield. The role of skin prick test with higher molecular weight PEGs requires further attention. Further studies are required to understand PEG thresholds and PEG equivalent doses of various administration routes. COVID-19 vaccines were tolerated by all exposed.

Vitamin B12 Hypersensitivity: A Retrospective Multicenter Study

BACKGROUND

Vitamin B12 (Vit B12) deficiency affects approximately 20% of those above the age of 60 years in the United Kingdom and United States. If untreated, it leads to detrimental health outcomes.

OBJECTIVE

To investigate a cohort of patients with Vit B12 hypersensitivity (VB12H) referred to 3 UK allergy centers and design a pathway for the investigation of VB12H.

METHODS

A total of 29 patients seen between 2014 and 2022 underwent skin prick testing (1 mg/mL) with cyanocobalamin (CC) and hydroxycobalamin (HC) and intradermal testing (0.1 and 0.01 mg/mL). Patients with negative skin tests underwent a Vit B12 drug provocation test (DPT) with either the index or the alternative drug.

RESULTS

Of 29 patients, 18 (62%) presented with immediate VB12H. Eight experienced anaphylaxis (4 to HC and 4 to CC) and had positive skin tests to the index drug. One patient reacted to oral and 7 patients to injectable Vit B12. Seven patients sensitized to one form of Vit B12-tolerated DPT with an alternative Vit B12. One patient with immediate VB12H reacted to polyethylene glycol (PEG) in oral cobalamin. Of 29 patients, 8 presented with delayed hypersensitivity reaction; 4 patients tolerated the intramuscular index formulation, whereas 2 patients tolerated the per oral formulation. One patient presented with symptoms consistent with symmetrical drug-related intertriginous and flexural exanthema. Three patients were referred because of cobalt allergy.

CONCLUSION

Confirmed VB12H is rare. We propose a comprehensive evaluation protocol that includes Vit B12 skin tests and considers PEG allergy in patients presenting with VB12H.

EAACI/ENDA position paper on drug provocation testing

In drug hypersensitivity, drug provocation testing (DPT), also called drug challenge, is the gold standard for investigation. In recent years, risk stratification has become an important tool for adjusting the diagnostic strategy to the perceived risk, whilst still maintaining a high level of safety for the patient. Skin tests are recommended before DPT but may be omitted in low-risk patients. The task force suggests a strict definition of such low-risk patients in children and adults. Based on experience and evidence from studies of allergy to beta-lactam antibiotics, an algorithm on how to adjust DPT to the risk, and when to omit skin tests before DPT, is presented. For other antibiotics, non-steroidal anti-inflammatory drugs and other drugs, skin tests are poorly validated and DPT is frequently necessary. We recommend performing DPT with chemotherapeutics and biologicals to avoid unnecessary desensitization procedures and DPT with skin tests negative contrast media. We suggest DPT with anesthetics only in highly specialized centers. Specifics of DPT to proton pump inhibitors, anticonvulsants and corticosteroids are discussed. This position paper provides general recommendations and guidance on optimizing use of DPT, whilst balancing benefits with patient safety and optimizing the use of the limited available resources.

Feasibility of a drug allergy registry-based excipient allergy database and call for universal mandatory drug ingredient disclosure: the case of PEG

Background

Excipient allergy is a rare, but potentially lethal, form of drug allergy. Diagnosing excipient allergy remains difficult in regions without mandatory drug ingredient disclosure and is a significant barrier to drug safety.

Objective

To investigate the feasibility of a drug allergy registry-based excipient database to identify potential excipient culprits in patients with history of drug allergy, using polyethylene glycol (PEG) as an example.

Methods

An excipient registry was created by compiling the excipient lists pertaining to all available formulations of the top 50 most reported drug allergy culprits in Hong Kong. Availability of excipient information, and its relationship with total number of formulations of individual drugs were analysed. All formulations were checked for the presence or absence of PEG.

Results

Complete excipient information was available for 36.5% (729/2,000) of all formulations of the top 50 reported drug allergy culprits in Hong Kong. The number of formulations for each drug was associated with proportion of available excipient information (ρ = 0.466, p = 0.001). Out of 729 formulations, 109 (15.0%) and 620 (85.0%) were confirmed to contain and not contain PEG, respectively. Excipient information was not available for the other 1,271 (63.6%) formulations. We were unable to confirm the presence or absence of PEG in any of the top 50 drug allergy culprits in Hong Kong.

Conclusion

In countries without mandatory drug ingredient disclosure, excipient databases are unlikely able to identify potential excipient allergy in drug allergy patients. Legislations to enforce mandatory and universal ingredient disclosure are urgently needed.

New Challenges in Drug Allergy: the Resurgence of Excipients

Purpose of Review

Allergy to excipients is a cause of multidrug allergy and if it is not taken into account, it can lead to unexpected severe reactions. If an excipient allergy is suspected, an accurate examination followed by algorithms is very important for a correct diagnosis and to give patients detailed information in order to avoid future reactions.

Recent Findings

In recent times, due to allergy COVID vaccine reactions, interest in excipients as polyethylene glycol derivatives (PEGs) has increased as a possible cause of drug and vaccine hypersensivity. In addition to PEGs many other excipients as gelatin, alpha-gal, protamine, benzalkonium chloride, and benzyl alcohol have been described as a cause of allergy to drugs and vaccines. For most excipients, the dilutions used for skin testing (ST) are not standardized and proper algorithms to reach a diagnosis are not available.

Summary

The purpose of this article is to review the excipients that may produce inmediate hypersensitivity drugs and vaccine reactions and update diagnostic procedures to reach an accurate diagnosis. We highlight the in vivo and in vitro diagnostic tests used in published reports and detail the dilution used for each excipient to perform ST in order to confirm this vital pathology and to prevent new reactions.

Carboxymethylcellulose excipient allergy: a case report

Background

Excipients are widely used in pharmaceuticals, detergents, food, and drink because of their properties of low toxicity and hypoallergenicity. The excipient carboxymethylcellulose is used extensively as a thickener in foods such as baked goods, ice cream, gluten free, and reduced fat products, where it may be labeled as e-number E466. However, excipients can rarely cause type 1 hypersensitivity reactions. Several publications have described systemic allergy following carboxymethylcellulose exposure in pharmaceuticals, particularly systemic corticosteroids. Furthermore, there is one reported case in the literature of anaphylaxis following food containing carboxymethylcellulose.

Case presentation

We identify a case of anaphylaxis in a 45-year-old atopic Caucasian woman on receiving an injectable suspension of the corticosteroid triamcinolone acetonide containing carboxymethylcellulose, and subsequent allergic symptoms on reexposure to carboxymethylcellulose in a commercial drink. Diagnosis of carboxymethylcellulose excipient allergy was confirmed through skin prick testing using Celluvisc carmellose 0.5% eye drops, which contain carboxymethylcellulose as the active ingredient.

Conclusion

This case highlights the importance of identifying excipients such as carboxymethylcellulose as causes of allergy, to reduce burden of further hypersensitivity reactions, not just to drugs but to other consumables.

Immediate hypersensitivity reactions to steroids and steroid containing medications

PURPOSE OF REVIEW

Although rare and counterintuitive, hypersensitivity reactions to corticosteroids have been reported since the 1950s. Delayed hypersensitivity reactions following cutaneous exposure (contact allergy) are well understood and principles of testing, as well as cross-reactivity patterns, have been established. In contrast, understanding of immediate hypersensitivity reactions and delayed hypersensitivity reactions after systemic exposure is evolving more slowly. However, progress has been made in the delineating of underlying pathogenic mechanisms and in the development of testing.

RECENT FINDINGS

IgE-mediated hypersensitivity reactions to corticosteroids have been described. It has been recognized that some, if not all of them, may be due to excipients in steroid formulations. Two excipients, polyethylene glycol and carboxymethylcellulose, seem of particular importance, but cases of reactions to polysorbate 80 and lactose have also been reported. The use of skin testing but also, increasingly, in-vitro methods such as basophil activation test is improving diagnostic accuracy.

SUMMARY

The recognition of the role of excipients is leading to a paradigm shift in our approach to immediate hypersensitivity to corticosteroids. Improved access to in-vivo and in-vitro testing will enhance our understanding of true corticosteroid immediate allergy.

Steroid Allergy in a Patient With Behçet's Disease

Immediate hypersensitivity reactions to systemic steroids are reported rarely in the literature. The authors present a case of Behçet's disease-associated panuveitis in a patient with skin test confirmed immunoglobulin E-mediated allergy to methylprednisolone and reported allergic reaction to prednisone. The patient tolerated prednisolone eyedrops for his anterior segment disease, as well as oral prednisolone for systemic therapy. This case demonstrates a challenge to conventional treatment, as it involves a hypersensitivity that is rarely reported. It also highlights class differences in corticosteroids with regard to immune reactivity. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:447-449.].

Hidden Dangers: Recognizing Excipients as Potential Causes of Drug and Vaccine Hypersensitivity Reactions

Excipients are necessary as a support to the active ingredients in drugs, vaccines, and other products, and they contribute to their stability, preservation, pharmacokinetics, bioavailability, appearance, and acceptability. For both drugs and vaccines, these are rare reactions; however, for vaccines, they are the primary cause of immediate hypersensitivity. Suspicion for these "hidden dangers" should be high, in particular, when anaphylaxis has occurred in association with multiple chemically distinct drugs. Common excipients implicated include gelatin, carboxymethylcellulose, polyethylene glycols, and products related to polyethylene glycols in immediate hypersensitivity reactions and propylene glycol in delayed hypersensitivity reactions. Complete evaluation of a suspected excipient reaction requires detailed information from the product monograph and package insert to identify all ingredients that are present and to understand the function and structure for these chemicals. This knowledge helps develop a management plan that may include allergy testing to identify the implicated component and to give patients detailed information for future avoidance of relevant foods, drugs, and vaccines. Excipient reactions should be particularly considered for specific classes of drugs where they have been commonly found to be the culprit (eg, corticosteroids, injectable hormones, immunotherapies, monoclonal antibodies, and vaccines). We provide a review of the evidence-based literature outlining epidemiology and mechanisms of excipient reactions and provide strategies for heightened recognition and allergy testing.

Consensus Statements on the Approach to COVID-19 Vaccine Allergy Safety in Hong Kong

Background: Mass coronavirus disease 2019 (COVID-19) vaccination to achieve herd immunity is an effective means to mitigate the current COVID-19 pandemic. Reports of COVID-19 vaccine-associated allergic reactions and lack of clear local guidance are contributing factors leading to a low vaccine acceptance rate in the community. A task force of experts from the Hong Kong Institute of Allergy (HKIA) has been formed to address current needs.

Objective: To formulate a set of consensus statements (CS) on COVID-19 vaccine allergy safety (VAS) in Hong Kong.

Methods: A nominated task force of experts managing patients with drug and vaccine allergies in Hong Kong formulated the CS by the Delphi method. An agreement was a priori defined as ≥80% consensus.

Results: A total of 11 statements met the criteria for consensus with good overall agreement among task force members, including seven statements on pre-vaccination recommendations and four statements on vaccination and post-vaccination guidance. Individuals with a history of suspected allergic reaction to prior COVID-19 vaccination should not receive further COVID-19 vaccination, and other groups at risk of COVID-19 vaccine-associated allergic reactions have been identified. The importance of pre-vaccination and post-vaccination assessment by frontline healthcare workers and evaluation by allergists are highlighted.

Conclusion: The CS provides pragmatic and timely guidance for local frontline healthcare providers on decisions regarding COVID-19 VAS.

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.

Delabeling Delayed Drug Hypersensitivity: How Far Can You Safely Go?

Delayed immune-mediated adverse drug reactions (IM-ADRs) are defined as reactions occurring more than 6 hours after dosing. They include heterogeneous clinical phenotypes that are typically T-cell-mediated reactions with distinct mechanisms across a wide spectrum of severity from benign exanthems through to life-threatening cutaneous or organ-specific diseases. For mild reactions such as benign exanthem, considerations for delabeling are similar to immediate reactions and may include a graded or single-dose drug challenge with or without preceding skin or patch testing. Evaluation of challenging cases such as the patient who is on multiple drugs at the time a severe delayed IM-ADR occurs should prioritize clinical ascertainment of the most likely phenotype and implicated drug(s). Although not widely available and validated, procedures such as patch testing, delayed intradermal skin testing, and laboratory-based functional drug assays or genetic (human leukocyte antigen) testing may provide valuable information to further help risk stratify patients and identify the likely implicated and/or cross-reactive drug(s). The decision to use a drug challenge as a diagnostic or delabeling tool in a patient with a severe delayed IM-ADR should weigh the risk-benefit ratio, balancing the severity and priority for the treatment of the underlying, and the availability of alternative efficacious and safe treatments.

Advances and novel developments in molecular allergology

The continuous search for new allergens and the design of allergen derivatives improves the understanding of their allergenicity and aids the design of novel diagnostic and immunotherapy approaches. This article discusses the recent developments in allergen and epitope discovery, allergy diagnostics and immunotherapy. Structural information is crucial for the elucidation of cross-reactivity of marker allergens such as the walnut Jug r 6 or that of nonhomologous allergens, as shown for the peanut allergens Ara h 1 and 2. High-throughput sequencing, liposomal nanoallergen display, bead-based assays, and protein chimeras have been used in epitope discovery. The binding of natural ligands by the birch pollen allergen Bet v 1 or the mold allergen Alt a 1 increased the stability of these allergens, which is directly linked to their allergenicity. We also report recent findings on the use of component-resolved approaches, basophil activation test, and novel technologies for improvement of diagnostics. New strategies in allergen-specific immunotherapy have also emerged, such as the use of virus-like particles, biologics or novel adjuvants. The identification of dectin-1 as a key player in allergy to tropomyosins and the formyl peptide receptor 3 in allergy to lipocalins are outstanding examples of research into the mechanism of allergic sensitization.

Multiple corticosteroids allergy in a patient with asthma: a case report

Background

Allergy towards systemic corticosteroid is rare. This case report discusses the investigations to confirm diagnosis and alternative treatments.

Case presentation

A 51-year-old asthmatic woman developed severe anaphylactic reaction following administration of systemic hydrocortisone. Skin prick, intradermal, and intravenous provocation tests confirmed allergy to triamcinolone, hydrocortisone, and dexamethasone. Skin prick tests (SPTs) were negative to all the aforementioned drugs. Intradermal test (IDT) with triamcinolone 1:10 concentration resulted in a 2-mm wheal associated with rhonchi. IDT with hydrocortisone 1:10 concentration showed an 8-mm wheal with rhonchi. IDTs to dexamethasone and carboxymethylcellulose were negative. Generalized rhonchi were observed with intravenous dexamethasone full concentration challenge.

Conclusions

Corticosteroid allergy should be suspected in asthma patients with worsening bronchospasm after its administration. Due to its rarity, such diagnosis can easily be missed, resulting in increased morbidity and mortality in patients.

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.

Multifaceted Actions of Succinate as a Signaling Transmitter Vary with Its Cellular Locations

Since the identification of succinate's receptor in 2004, studies supporting the involvement of succinate signaling through its receptor in various diseases have accumulated and most of these investigations have highlighted succinate's pro-inflammatory role. Taken with the fact that succinate is an intermediate metabolite in the center of mitochondrial activity, and considering its potential regulation of protein succinylation through succinyl-coenzyme A, a review on the overall multifaceted actions of succinate to discuss whether and how these actions relate to the cellular locations of succinate is much warranted. Mechanistically, it is important to consider the sources of succinate, which include somatic cellular released succinate and those produced by the microbiome, especially the gut microbiota, which is an equivalent, if not greater contributor of succinate levels in the body. Continue learning the critical roles of succinate signaling, known and unknown, in many pathophysiological conditions is important. Furthermore, studies to delineate the regulation of succinate levels and to determine how succinate elicits various types of signaling in a temporal and spatial manner are also required.

The Journal of Allergy and Clinical Immunology: In Practice 2018 Highlights

A large number of clinically impactful studies and reviews were published in this journal in 2018. This article provides highlights of the original research published in 2018 issues of The Journal of Allergy and Clinical Immunolgy: In Practice on the subjects of anaphylaxis, asthma, dermatitis, drug allergy, eosinophilic disorders, food allergy, immune deficiency, rhinitis, and urticaria/angioedema and mast cell disorders. Within each topic, practical aspects of diagnosis and management are emphasized. Treatments discussed include lifestyle modifications, allergen avoidance therapy, positive and negative effects of pharmacologic therapy, and various forms of immunologic and desensitization management. We hope this review will help readers consolidate and use this extensive and practical knowledge for the benefit of patients.