Hypersensitivity reactions to nonsteroidal anti-inflammatory drugs: from phenotyping to genotyping

Ibuprofen and Other Arylpropionics: The Relevance in Immediate Hypersensitivity Drug Reactions

BACKGROUND

Ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), is the most frequent medication to be involved in hypersensitivity drug reactions (HDRs). Other analgesic/anti-inflammatory drugs in the arylpropionic group are also relevant, albeit to a lesser extent. Ibuprofen is widely consumed by people of all ages, both on medical prescription and over the counter; moreover, it is an organic contaminant of surface waters and foods. While numerous drugs cause HDR, ibuprofen's underlying mechanisms are more intricate and involve both specific immunological and non-immunological mediated reactions.

SUMMARY

we concentrate on immediate responses, including urticaria with or without angioedema, anaphylaxis, and angioedema, classifying reactions according to whether they are caused by single or multiple NSAIDs and based on the mechanisms at play. Both groups may experience anaphylaxis, defined as an immediate, severe systemic reaction involving at least two organs, though the frequency and severity can vary. Following this classification, more clinical manifestations can be identified. Diagnosis is partly based on a detailed clinical history, including information about ibuprofen and/or other arylpropionic derivatives involved, the interval between drug intake and symptoms onset, clinical manifestations, number of episodes, and the patient's tolerance or response to other medications - mainly non-chemically related NSAID - both before and after reactions to ibuprofen and/or other arylpropionic drugs. A drug provocation test is frequently necessary to make a diagnosis.

KEY MESSAGE

Because ibuprofen is the most widely prescribed NSAID, it is reasonable to assume its role as the leading cause of HDR will only become more important.

Immunological Mechanisms in Cutaneous Adverse Drug Reactions

Adverse drug reactions (ADRs) are an inherent aspect of drug use. While approximately 80% of ADRs are predictable, immune system-mediated ADRs, often unpredictable, are a noteworthy subset. Skin-related ADRs, in particular, are frequently unpredictable. However, the wide spectrum of skin manifestations poses a formidable diagnostic challenge. Comprehending the pathomechanisms underlying ADRs is essential for accurate diagnosis and effective management. The skin, being an active immune organ, plays a pivotal role in ADRs, although the precise cutaneous immunological mechanisms remain elusive. Fortunately, clinical manifestations of skin-related ADRs, irrespective of their severity, are frequently rooted in immunological processes. A comprehensive grasp of ADR morphology can aid in diagnosis. With the continuous development of new pharmaceuticals, it is noteworthy that certain drugs including immune checkpoint inhibitors have gained notoriety for their association with ADRs. This paper offers an overview of immunological mechanisms involved in cutaneous ADRs with a focus on clinical features and frequently implicated drugs.

Descriptive Analysis of Cross-Reactive Anaphylaxis as a Different Clinical Subtype of Nonsteroidal Anti-Inflammatory Drug (NSAID) Hypersensitivity

INTRODUCTION

The European Network of Drug Allergy and the European Academy of Allergy and Clinical Immunology have classified hypersensitivity reactions induced by nonsteroidal anti-inflammatory drugs (NSAIDs) into 5 phenotypes according to the pathophysiology, clinical manifestations, number of drugs involved, and the presence of underlying diseases. This classification does not include anaphylaxis as part of NSAID cross-reactivity. The objective of this study was to characterize a group of patients with anaphylactic NSAID cross-reactivity.

METHOD

This was a retrospective, descriptive, observational study. Patients who developed anaphylaxis to one NSAID plus another acute reaction (anaphylactic or not) to at least one other NSAID of a different chemical group were included. Demographic and clinical characteristics and the diagnostic approach were studied.

RESULTS

A total of 38 patients were included, 28 (73.7%) of whom were women. The mean age was 40 ± 17.7 years. The main organs affected in the anaphylactic reaction were the skin and the respiratory system, occurring in 35 (92.1%) and 33 (86.8%) patients, respectively. Thirty-two (84.3%) patients presented with cutaneous and respiratory involvement simultaneously. The main anti-inflammatory agent involved in anaphylactic reactions was acetylsalicylic acid in 9 (23.7%) patients, followed by dipyrone in 8 (21.1%). The most frequent allergic comorbidity was rhinitis in 20 (52%) patients. Skin tests were performed in 15 (39.5%) patients, showing positivity in 12 (80%), mainly to mites. A total of 36 of 38 patients were challenged with alternative drugs, and 35 (97.2%) tolerated meloxicam and/or etoricoxib.

CONCLUSION

In the present study, NSAID cross-anaphylaxis was more frequent in women, and acetylsalicylic acid and dipyrone were the main triggers. Rhinitis was the main allergic comorbidity, and there was a high incidence of atopy. The majority tolerated selective COX-2 NSAIDs.

Evaluation of Subjects Experiencing Allergic Reactions to Non-Steroidal Anti-Inflammatory Drugs: Clinical Characteristics and Drugs Involved

Non-steroidal anti-inflammatory drugs (NSAIDs), the most commonly prescribed and consumed medicines worldwide, are the main triggers of drug hypersensitivity reactions (DHRs). The underlying mechanisms of NSAID-DHRs may be related to COX-1 inhibition (cross-hypersensitivity reactions, CRs) or to immunological recognition (selective reactions, SRs), being the latter remarkably less studied. SRs include those usually appearing within the first hour after drug intake (single-NSAID-induced urticaria/angioedema or anaphylaxis, SNIUAA), and those usually occurring more than 24 h after (single-NSAID-induced delayed reactions, SNIDR). We have evaluated the largest series of patients with SRs, analyzing the number of episodes and drugs involved, the latency for reaction onset, the clinical entities, among other variables, as well as the value of available diagnostic methods. Globally, pyrazolones and arylpropionics were the most frequent culprits (39.3% and 37.3%, respectively). Pyrazolones were the most frequent triggers in SNIUAA and arylpropionics in SNIDR. Urticaria was the most common clinical entity in SNIUAA (42.4%) followed by anaphylaxis (33.3%); whereas SNIDR induced mostly fixed drug eruption (41.1%) and maculopapular exanthema (32.6%). The percentage of patients diagnosed by clinical history was higher in SNIUAA compared with SNIDR (62.7% versus 35.3%, p = 0.00015), whereas the percentage of those diagnosed by skin tests was higher in SNIDR than in SNIUAA (47.1% versus 22.8%, p = 0.00015). Drug provocation test with the culprit was performed in 67 SNIUAA (14.5%) and in 9 SNIDR (17.6%) patients. Our results may be of interest not only for allergologists but also for other clinicians dealing with these drugs, and can be useful for the correct identification of subjects experiencing DHRs to NSAIDs, and for avoiding mislabeling. Moreover, as NSAIDs are highly consumed worldwide, our results may be of interest for evaluating other populations exposed to these drugs.

NSAID-induced reactions: classification, prevalence, impact, and management strategies

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the leading cause of hypersensitivity drug reactions. The different chemical structures, cyclooxygenase 1 (COX-1) and/or COX-2 inhibitors, are taken at all ages and some can be easily obtained over the counter. Vasoactive inflammatory mediators like histamine and leukotriene metabolites can produce local/systemic effects. Responders can be selective (SR), IgE or T-cell mediated, or cross-intolerant (CI). Inhibition of the COX pathway is the common mechanism in CI, with the skin being the most frequent organ involved, followed by the lung and/or the nose. An important number of cases have skin and respiratory involvement, with systemic manifestations ranging from mild to severe anaphylaxis. Among SR, this is the most frequent entity, often being severe. Recent years have seen an increase in reactions involving the skin, with many cases having urticaria and/or angioedema in the absence of chronic urticaria. Aspirin, the classical drug involved, has now been replaced by other NSAIDs, with ibuprofen being the universal culprit. For CI, no in vivo/in vitro diagnostic methods exist and controlled administration is the only option unless the cases evaluated report repetitive and consistent episodes with different NSAIDs. In SR, skin testing (patch and intradermal) with 24-48 reading can be useful, mainly for delayed T-cell responses. Acetyl salicylic acid (ASA) is the test drug to establish the diagnosis and confirm/exclude CI by controlled administration. Desensitization to ASA has been extensively used in respiratory cases though it can also be applied in those cases where it is required.

Angioedema: Clinical Presentations and Pharmacological Management

Angioedema (AE) is a unique clinical presentation of an unchecked release of bradykinin. The origin of this clinical presentation can be either genetic or acquired. The outcome within the patient is subcutaneous swelling of the lower layers of the epidermis. Symptoms are most often localized to the upper airway or the gastrointestinal tract. A typical course resolves in 5 to 7 days, but in some patients, the clinical manifestations exist up to 6 weeks. Hereditary AE is rare and genetically linked, and typically, the patient has episodes for many years before diagnosis. Episodes of acquired AE may be drug induced, triggered by a specific allergen, or idiopathic. Angioedema can elicit the need for critical care interventions, for advanced airway management, or unnecessary abdominal surgery. The treatment for these patients is evolving as new pharmacological agents are developed. This article addresses subtypes of AE, triggers, pharmacology, and information for interdisciplinary team planning of individualized case management.

Practical approach to the treatment of NSAID hypersensitivity

INTRODUCTION

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most frequently involved in drug hypersensitivity reactions (DHR). NSAIDs are prescribed for different processes and some NSAIDs can be obtained over the counter. Areas covered: We analyse the practical approaches for managing and treating NSAID-DHR considering the five major groups of entities recognised, divided into two categories: those responding to strong COX-1 inhibitors and possibly weak COX-1 or selective COX-2 inhibitors named cross-intolerant (CI), and those induced by a single drug or drug group with good tolerance to strong COX-1 inhibitors, known as allergic reactions (SR). An analysis of the recent literature indicates that two approaches can be followed for CI: to give acetyl salicylic acid to confirm NSAID hypersensitivity or to give alternative drugs to provide a solution for the treatment of pain, fever, inflammation or other conditions. Desensitisation approaches have been undertaken, but mainly for CI cases with respiratory airway involvement and they are very rarely used for CI with cutaneous involvement or SR. Expert commentary: DHR to NSAIDs are now recognised as one of the most important problems in the evaluation and management of drug allergy. Because no diagnostic tests exist, important resources are needed to evaluate these patients.

Angioedema associated with nonsteroidal anti-inflammatory drugs

PURPOSE OF REVIEW

The review critically assesses the different phenotypes of angioedemas associated with NSAIDs. Angioedemas exacerbated or induced by NSAIDs have high morbidity and, when they affect the larynx, can lead to death by asphyxiation.

RECENT FINDINGS

Angioedema can present as a manifestation of a syndrome such as anaphylaxis or it can be a separate entity, which comprises different forms that can be diagnosed based on specific criteria. NSAIDs are the drugs most used worldwide and they are also one of the leading causes of angioedema.

SUMMARY

The manuscript addresses the pathophysiology and pharmacogenetics of angioedema, reviews its classification and assesses the diagnosis and management of angioedemas exacerbated and induced by NSAIDs.

Asthma and Rhinitis Induced by Selective Immediate Reactions to Paracetamol and Non-steroidal Anti-inflammatory Drugs in Aspirin Tolerant Subjects

In subjects with non-steroidal anti-inflammatory drugs (NSAIDs)- exacerbated respiratory disease (NERD) symptoms are triggered by acetyl salicylic acid (ASA) and other strong COX-1 inhibitors, and in some cases by weak COX-1 or by selective COX-2 inhibitors. The mechanism involved is related to prostaglandin pathway inhibition and leukotriene release. Subjects who react to a single NSAID and tolerate others are considered selective responders, and often present urticaria and/or angioedema and anaphylaxis (SNIUAA). An immunological mechanism is implicated in these reactions. However, anecdotal evidence suggests that selective responders who present respiratory airway symptoms may also exist. Our objective was to determine if subjects might develop selective responses to NSAIDs/paracetamol that manifest as upper/lower airways respiratory symptoms. For this purpose, we studied patients reporting asthma and/or rhinitis induced by paracetamol or a single NSAID that tolerated ASA. An allergological evaluation plus controlled challenge with ASA was carried out. If ASA tolerance was found, we proceeded with an oral challenge with the culprit drug. The appearance of symptoms was monitored by a clinical questionnaire and by measuring FEV1 and/or nasal airways volume changes pre and post challenge. From a total of 21 initial cases, we confirmed the appearance of nasal and/or bronchial manifestations in ten, characterized by a significant decrease in FEV1% and/or a decrease in nasal volume cavity after drug administration. All cases tolerated ASA. This shows that ASA tolerant subjects with asthma and/or rhinitis induced by paracetamol or a single NSAID without skin/systemic manifestations exist. Whether these patients represent a new clinical phenotype to be included within the current classification of hypersensitivity reactions to NSAIDs requires further investigation.

Immediate hypersensitivity reactions to ibuprofen and other arylpropionic acid derivatives

BACKGROUND

Although ibuprofen and other arylpropionic acid derivatives (APs) are the most common medicines involved in hypersensitivity drug reactions (HDRs) to NSAIDs, no patient series studies have been performed regarding immediate selective reactions (SRs) to these drugs.

OBJECTIVE

To characterize patients with immediate selective HDRs to ibuprofen and other APs through clinical history and challenge.

METHODS

Subjects who developed an HDR to APs less than 1 h after drug intake were included. Tolerance to aspirin was assessed and challenge was performed with ibuprofen in all cases, and additionally with the culprit drug (if different) in those patients that tolerated ibuprofen. Serum tryptase levels and tryptase immunohistochemical staining in skin biopsies were also assessed in some patients with a positive DPT to ibuprofen.

RESULTS

From a total of 245 patients with a confirmed history of HDRs to APs, 17% were classified as selective immediate hypersensitivity reactors by both clinical history and challenge. A selective response to naproxen and dexketoprofen with tolerance to ibuprofen was found in 16 of 20 cases. Significant differences in serum tryptase levels were observed between 2 and 24 h in the 11 cases that were studied further.

CONCLUSIONS

Within the group of patients with HDRs to NSAIDs, APs can induce immediate SRs. Within this group, selective responses to a single drug or responders to several APs may exist, suggesting potential immunological cross-reactivity.

Approaches to the diagnosis and management of patients with a history of nonsteroidal anti-inflammatory drug-related urticaria and angioedema

Nonsteroidal anti-inflammatory drug (NSAID)-induced urticarial and angioedema reactions are among the most commonly encountered drug hypersensitivity reactions in clinical practice. Three major clinical phenotypes of NSAID-induced acute skin reactions manifesting with angioedema, urticaria, or both have been distinguished: NSAID-exacerbated cutaneous disease, nonsteroidal anti-inflammatory drug-induced urticaria/angioedema (NIUA), and single NSAID-induced urticaria and angioedema. In some patients clinical history alone might be sufficient to establish the diagnosis of a specific type of NSAID hypersensitivity, whereas in other cases oral provocation challenges are necessary to confirm the diagnosis. Moreover, classification of the type of cutaneous reaction is critical for proper management. For example, in patients with single NSAID-induced reactions, chemically nonrelated COX-1 inhibitors can be safely used. However, there is cross-reactivity between the NSAIDs in patients with NSAID-exacerbated cutaneous disease and NIUA, and thus only use of selective COX-2 inhibitors can replace the culprit drug if the chronic treatment is necessary, although aspirin desensitization will allow for chronic treatment with NSAIDs in some patients with NIUA. In this review we present a practical clinical approach to the patient with NSAID-induced urticaria and angioedema.