Drug provocation tests in the diagnosis of hypersensitivity reactions to non-steroidal anti-inflammatory drugs in children

Risk factors for drug hypersensitivity reactions in children

Drug hypersensitivity reactions are common in children. Risk factors predisposing to IgE-mediated drug allergies and delayed drug reactions are a matter of debate. Gender, age, previous reactions to the same drug or to another drug, reduced drug metabolism, chronic diseases, polypharmacy, drug doses are linked with the onset of hypersensitivity reactions in some children. Novel advances in genetic polymorphisms can rapidly change the approach to the prevention of reactions since gene testing can be a useful screening test for severe cutaneous adverse reactions. Viral infections may act as cofactors in susceptible individuals. Polypharmacy, high doses, repeated doses and parental route of administration are also risk factors. Clinicians should take into account risk factors to allow the risk-benefit balance to be maintained.

Diagnostic evaluation of hypersensitivity reactions to arylpropionic acid derivatives: a descriptive observational study focusing on clinical characteristics and potential risk factors in children

BACKGROUND

Arylpropionic acid derivatives (APs) are the main triggers of nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. Data on clinical patterns and risk factors for AP hypersensitivity in children are quite limited.

AIM

To assess the clinical characteristics and potential risk factors for proven AP hypersensitivity in children.

METHOD

Patients with a history of AP hypersensitivity were retrospectively assessed using a standardized diagnostic algorithm. Children with confirmed hypersensitivity were defined as selective responders or cross-intolerants based on the result of drug provocation tests and further categorized according to the EAACI/ENDA classification. A multivariable logistic regression analysis was performed to analyze the potential risk factors for proven AP hypersensitivity.

RESULTS

A total of 166 patients (51.2% male, median age of six years) with a history of AP hypersensitivity were included. Ibuprofen (89.2%) was the most frequently reported AP in the patients' histories. The reported hypersensitivity of 40 (22.4%) patients was confirmed by diagnostic testing: eight (13.6%) patients with a history of reaction only to APs and 32 (29.9%) patients with a history of reactions to multiple NSAIDs, including chemically unrelated NSAIDs in addition to APs. Five (12.5%) patients were classified as selective responders and 35 (87.5%) were cross-intolerants. Overall, five (12.5%) of the confirmed cases could not be categorized according to the EAACI/ENDA classification. Older age (aOR: 1.11, 95% CI 1.02-1.21, p = 0.015), chronic urticaria as an underlying disease (aOR: 2.87, 95% CI 1.09-7.54, p = 0.033) and a history of anaphylaxis (aOR: 7.84, 95% CI 1.86-33.04, p = 0.005) were related to confirmed AP hypersensitivity.

CONCLUSION

Almost a quarter of children and adolescents were confirmed to have AP hypersensitivity. Older age, the presence of chronic urticaria and a history of anaphylaxis were potential risk factors for proven AP hypersensitivity.

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.

Evaluation of different protocols for classification of pediatric hypersensitivity reactions to nonsteroidal anti-inflammatory drugs: Children with underlying allergic disease should be a separate subgroup

Background: Different recommendations for the classification of nonsteroidal anti-inflammatory drug hypersensitivity reactions (NSHSR) in children have been reported but a shortage still exists. Objective: The aim of the present study was to evaluate the inclusivity of two European Academy of Allergy and Clinical Immunology (EAACI) position paper classifications and to characterize the factors that underlie classification discordance in children. Methods: Patients with a history of NSHSR were evaluated with a standardized diagnostic protocol according to EAACI/ European Network for Drug Allergy (ENDA) recommendations. Children were classified and compared according to the EAACI 2013 and the pediatric EAACI/ENDA 2018 classifications. Subjects who were unclassified and those who were classified were compared. Results: Of 232 patients (median [interquartile range] age 6 years (4-11 years) with a history of NSHSR, 52 (22.4%) were confirmed with diagnostic tests. Thirty-six (69.2%) were classified as having cross-intolerance, whereas 16 patients (30.8%) were classified as selective responders. Eleven of the confirmed cases (21.2%) could not be categorized according to the 2013 EAACI classification, whereas this number was six adolescents (11.5%) when the 2018 EAACI/ENDA pediatric classification was used. Patients who were unclassified and who were all cross-intolerant were more likely to have atopic sensitization (p = 0.001) and asthma as an underlying disease (p = 0.03), higher serum eosinophil count (p = 0.022), and total immunoglobulin E levels (p = 0.007) compared with those who fit well into the classification. In multivariate regression analysis, the presence of atopic sensitization (adjusted odds ratio 20.36 [95% confidence interval, 2.14-193.48]; p = 0.009) was found to be the only significant underlying factor for an unclassified and/or blended phenotype. Conclusion: The 2013 EAACI classification resulted in a high rate of subjects who were unclassified. Despite better clinical utility, the recent pediatric EAACI/ENDA classification system still has shortcomings in terms of inclusivity for adolescents. Mostly, children with underlying allergic diseases could not be classified by the current guidelines. We propose to classify them as a separate pediatric cross-intolerance subgroup because the underlying mechanism may involve more than cyclooxygenase 1 inhibition.

An Update on Nonsteroidal Anti-Inflammatory Drug-Induced Urticaria

BACKGROUND

Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (HR-NSAIDs) are common adverse events related to the widespread use of over-the-counter NSAIDs for the treatment of a variety of inflammatory conditions. Urticaria is the most commonly reported immediate cutaneous clinical sign of HR-NSAIDs, but it can be a manifestation of pathophysiologically different clinical entities that require different therapeutic strategies. The aim of this study is to ease the identification of the correct phenotype of HR-NSAIDs in patients reporting urticaria associated with the intake of NSAIDs and provide updated information about their diagnosis and management.

METHODS

The study is a narrative review conducted by collecting the most relevant and up-todate data related to the classification, pathophysiology, severity, and prognosis of NSAID hypersensitivity reactions. PubMed and Embase scientific databases were used as search engines to select relevant articles.

RESULTS

Patients developing HR-NSAIDs can be divided into two categories: selective responders (SR), who develop reactions after the administration of a single specific NSAID due to an underlying IgE or T-cell mediated hypersensitivity mechanism, or cross-intolerant (CI), who develop reactions to more than one chemically unrelated NSAIDs due to abnormalities in the biochemical pathways related with prostaglandin metabolism, independently from an underlying immunological mechanism. Five major different categories of HR-NSAIDs have been identified: NSAIDs-exacerbated cutaneous disease (NECD), NSAIDs-induced urticaria/angioedema with/without respiratory and systemic symptoms of anaphylaxis (NIUAA), and NSAIDsexacerbated respiratory disease (NERD), which are developed by CI patients, and single NSAIDs-induced urticaria, angioedema and/ or anaphylaxis (SNIUAA) and single NSAIDsinduced delayed hypersensitivity reactions (SNIDHR), which are developed by CI patients. In vivo and in vitro diagnostic tests have rarely been shown to be reliable in all these entities and therefore are not routinely used in clinical practice. The management in SR patients consists of strict avoidance of the culprit drug, while for cross-intolerance reactions oral tolerance tests with safe alternative drugs (e.g. weak COX-1 inhibitors or selective COX-2 inhibitors) can be performed.

CONCLUSION

HR-NSAIDs are being observed with increasing frequency, however, the pathogenesis behind some NSAIDS-associated clinical entities is still unclear. Diagnosis is mostly based on a thorough clinical history and confirmed by a drug challenge test. Clinical management is based on strict avoidance and use of alternative tolerated medications. Overall, all therapeutic decisions depend on the correct identification of the type of reaction the patient experienced.

Different Patterns of Response in Hypersensitivity Reactions to Arylpropionic Acid Derivatives

BACKGROUND

Ibuprofen and other arylpropionic acid derivatives (APs) are among the most consumed nonsteroidal anti-inflammatory drugs worldwide at all age ranges; however, little is known about drug hypersensitivity reactions (DHRs) they induce.

OBJECTIVE

To characterize in detail patients reporting DHRs to APs.

METHODS

We prospectively evaluated patients with symptoms suggestive of AP-DHRs and analyzed their clinical characteristics, reported reactions, and diagnostic approaches.

RESULTS

Six hundred sixty-two patients confirmed as hypersensitive to APs were included: 489 with cross-reactive reactions (CRs) (73.86%) and 173 with selective reactions (SRs) (26.13%). The percentage of subjects reporting reactions to ibuprofen and dexketoprofen was higher in CRs (P = .005 and P = .01, respectively), whereas naproxen and ketoprofen were more frequently involved in SRs (P = .0002 and P = .00001, respectively). The most frequent symptoms induced by ibuprofen, dexketoprofen, and naproxen were isolated angioedema and urticaria, combined or not with angioedema in both CRs and SRs. The result of nasal provocation test with lysine acetylsalicylate was positive in 156 cases (77.14% in patients showing exclusively respiratory symptoms, and in 68.18% of those with both cutaneous and respiratory involvement). To confirm diagnosis, drug provocation test with acetylsalicylic acid was required in 246 CR patients (50.3%), whereas in 28 SR patients (16.18%) drug provocation test with the culprit AP was required.

CONCLUSIONS

Skin is the organ most commonly involved in AP-DHRs, with ibuprofen and dexketoprofen inducing most frequently CRs, and naproxen and ketoprofen SRs. More studies are necessary to clarify the underlying mechanism in DHRs induced by APs.

Practical Approach to Hypersensitivity to Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) in Children

BACKGROUND

We aimed to assess the real-life prevalence, patient profile, and clinical presentation of drug hypersensitivity to NSAIDs in children after an incidence of an adverse event during treatment, verified by a drug challenge test.

METHODS

We included 56 children, aged 4-18 years, referred to our allergy clinic due to the incidence of adverse reaction during treatment. Skin prick tests and a drug provocation test were performed in all patients. Diagnostics for persistent urticaria were performed.

RESULTS

In 56 patients suspected of drug allergy, we proved NSAID hypersensitivity in 17 patients (30.1%). In 84.9% (n = 47) of patients, the clinical manifestations of hypersensitivity revealed angioedema and urticaria. The most common culprit drug among NSAIDs in children was ibuprofen. Thirty-one (55.4%) reactions were immediate, and 25 (44.6%) were delayed or late. Previous history of allergy was a risk factor for NSAID hypersensitivity (p = 0.001). Vitamin D deficiency in the blood serum was a risk factor for NASID hypersensitivity (OR = 5.76 (95% Cl: 1.42-23.41)).

CONCLUSIONS

Hypersensitivity to NSAIDs is a difficult diagnostic problem in pediatric allergy. The most common manifestation of hypersensitivity to ibuprofen in children is acute urticaria and angioedema. Two important problems in the differential diagnosis are cofactors such as vitamin D levels and viral infections, which require further research.

Efficacy and Safety of NSAIDs in Infants: A Comprehensive Review of the Literature of the Past 20 Years

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in infants, children, and adolescents worldwide; however, despite sufficient evidence of the beneficial effects of NSAIDs in children and adolescents, there is a lack of comprehensive data in infants. The present review summarizes the current knowledge on the safety and efficacy of various NSAIDs used in infants for which data are available, and includes ibuprofen, dexibuprofen, ketoprofen, flurbiprofen, naproxen, diclofenac, ketorolac, indomethacin, niflumic acid, meloxicam, celecoxib, parecoxib, rofecoxib, acetylsalicylic acid, and nimesulide. The efficacy of NSAIDs has been documented for a variety of conditions, such as fever and pain. NSAIDs are also the main pillars of anti-inflammatory treatment, such as in pediatric inflammatory rheumatic diseases. Limited data are available on the safety of most NSAIDs in infants. Adverse drug reactions may be renal, gastrointestinal, hematological, or immunologic. Since NSAIDs are among the most frequently used drugs in the pediatric population, safety and efficacy studies can be performed as part of normal clinical routine, even in young infants. Available data sources, such as (electronic) medical records, should be used for safety and efficacy analyses. On a larger scale, existing data sources, e.g. adverse drug reaction programs/networks, spontaneous national reporting systems, and electronic medical records should be assessed with child-specific methods in order to detect safety signals pertinent to certain pediatric age groups or disease entities. To improve the safety of NSAIDs in infants, treatment needs to be initiated with the lowest age-appropriate or weight-based dose. Duration of treatment and amount of drug used should be regularly evaluated and maximum dose limits and other recommendations by the manufacturer or expert committees should be followed. Treatment for non-chronic conditions such as fever and acute (postoperative) pain should be kept as short as possible. Patients with chronic conditions should be regularly monitored for possible adverse effects of NSAIDs.

NSAID Hypersensitivity in the Pediatric Population: Classification and Diagnostic Strategies

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently administered drugs, mainly for their anti-pyretic, but also for pain-relieving and anti-inflammatory effects in children. NSAIDs are composed of structurally divergent subgroups of drugs with similar pharmacological and adverse effects. Aspirin originates from salicin and was the first synthesized analgesic. As a prototype of NSAIDs; aspirin-induced hypersensitivity reactions were first reported, but subsequently, other phenotypes of hypersensitivity reactions were also described with aspirin and other NSAIDs. There are certain challenging aspects of NSAID-hypersensitivity in the pediatric population that need to be further investigated. These include the effect of age on drug metabolism and the natural history of the various phenotypes of NSAID-hypersensitivity, the effect of certain co-factors (infections, exercise) on NSAID-hypersensitivity, and diagnostic clinical and laboratory biomarkers clarifying the endotypes. In recent years, a non-negligible number of case series, studies and expert panel reports have been published in this field with some novel features and diagnostic modalities in the pediatric population. With the current review; the clinical phenotypes and diagnostic and management modalities of suspected NSAID-induced hypersensitivity reactions in childhood and adolescence were explained and updated by examining past and current publications.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs.

Behind the scene: Paracetamol hypersensitivity in children

BACKGROUND

Paracetamol, a non-steroidal anti-inflammatory drug, is commonly being used for fever and pain relief worldwide. The aim of this study was to evaluate children with a suspected history of paracetamol hypersensitivity.

METHODS

Sixty patients who were referred to our clinic in between January 2015 and December 2018 with a suspected history of paracetamol hypersensitivity were included. Reactions were classified according to the European Network for Drug Allergy (ENDA)/Global Allergy and Asthma European Network classification and European Academy of Allergy and Clinical Immunology (EAACI)/ENDA Position Paper. Diagnoses were confirmed by skin tests and oral challenge tests (OCTs). In those with verified paracetamol hypersensitivity, an OCT with a strong COX-1 inhibitor was performed to classify the type of the reaction to refer as either selective or cross-intolerance hypersensitivity. A subsequent OCT with a selective COX-2 inhibitor was performed in those cross-intolerant patients to find out a safe alternative drug.

RESULTS

Sixty OCTs with paracetamol were performed to patients with a median age of 8.5 years, and hypersensitivity to paracetamol was verified in 8 patients. Four children were classified as selective responders, and 3 were classified as cross-intolerant after OCT with a COX-1 inhibitor. Overall, skin test positivity for paracetamol was detected in only one patient, in whom OCT with paracetamol was negative. In all 3 cross-intolerant patients, a safe alternative non-steroidal anti-inflammatory drug was identified after an OCT with a selective COX-2 inhibitor.

CONCLUSION

OCT stands as the gold-standard procedure in verifying the diagnosis of patients with paracetamol-induced drug hypersensitivity, as well as, in defining the type of reactions and finding out safe alternative drugs.

Characteristics and Contributing Factors Related to Nonsteroidal Anti-Inflammatory Drugs Hypersensitivity

INTRODUCTION

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) is reported to be the most common drug hypersensitivity. The aim of this study was to evaluate the characteristics of self-reported NSAID hypersensitivity and identify patients at high risk of NSAID hypersensitivity.

METHODS

Patients who presented at a single tertiary care hospital between January-December 2017 with reported NSAID hypersensitivity were evaluated. Clinical information obtained from a review of medical records was further supplemented with data gained from a telephone-administered questionnaire.

RESULTS

From a total of 535 patients with reported NSAID hypersensitivity, 301 were included in the study. The mean age of onset of NSAID hypersensitivity reaction was 30.3 ± 14.9 years old. A total of 84 patients (27.9%) were hypersensitive to 2 or more chemically unrelated NSAIDs. The leading NSAID hypersensitivity was to propionic acid derivatives (73%) followed by acetic acid derivatives (28.9%). Immediate reaction (≤1 h) was identified in 171 patients (57.8%), and angioedema was the most frequently reported symptom (179 patients, 59.5%), followed by urticaria and anaphylaxis in 85 (28.2%) and 62 (20.6%) patients, respectively. A drug provocation test was performed on 53 patients, and NSAID hypersensitivity was confirmed in 38 patients (71.6%). The independent factors identified, which could predict NSAID hypersensitivity, were personal history of allergic rhinitis/chronic rhinosinusitis (AR/CRS), onset of NSAID hypersensitivity over 15 years old, and immediate reaction.

CONCLUSION

Angioedema was the most typical symptom, and propionic acid derivatives were the most frequently reported culprit drugs. The significant risk factors predicting NSAID hypersensitivity were personal history of AR/CRS, onset of NSAID hypersensitivity reaction over 15 years old, and immediate reaction.

Drug Allergy in Children: What Should We Know?

The drug allergy "label" may have a lifetime of consequences for a child. Many children with alleged drug allergies are proven to be tolerant to the culprit medication when challenged. The field of drug hypersensitivity is a recently evolving field of research, but studies on its epidemiology and diagnostic tools are lacking in children. Clinical history is significant in the diagnosis and classification of drug hypersensitivity in children. Diagnostic tools have been evaluated in a limited number of children; therefore, the guidelines are mainly in line with those for adults. Here, we review the clinical characteristics, main drugs, risk factors, and diagnosis of drug hypersensitivity to aid in its accurate diagnosis in children.

Data-driven step doses for drug provocation tests to nonsteroidal anti-inflammatory drugs

INTRODUCTION

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) is of great concern because they are frequently encountered in daily clinical practice. Drug provocation tests (DPTs) are particularly needed for NSAIDs.

METHODS

The aim of this retrospective study was to detect eliciting dose thresholds during NSAIDs DPT in order to suggest optimal step doses, using the survival analysis method. Our secondary objective was to describe subgroups at higher risk during DPT and evaluate the safety of our 30 minutes incremental 1-day protocol. The study comprised all the patients attended the Allergy of the University Hospital of Montpellier (France), between 1997 and 2017 for a suspicion of drug hypersensitivity reaction to NSAIDs.

RESULTS

Throughout the study period, 311 positive DPT were analyzed (accounting for 285 hypersensitive patients). We identified eliciting thresholds (dose and time), and we suggest the following steps for future DPT: for the rapid absorption group (acetylsalicylic acid, ibuprofen, ketoprofen, and tiaprofenic acid), every 30 minutes: 20%-30%-50% of daily therapeutic dose, for the moderate absorption group, every 30 minutes: for diclofenac 5%-15%-30%-50%, and for celecoxib, 20%-80%. For the slow absorption group, piroxicam, 25%-75%, was separated by a 3-hours interval. A surveillance period of 3 hours after the last dose is mandatory for patients.

CONCLUSION

Drug provocation test protocols for NSAID are empirical, driven by the knowledge on patterns of DHR, cross-reactivity between NSAID and pharmacological effects of these all drugs. This is the second experience in improving DPT protocols, after BL (B-lactam) antibiotics.

Results of NSAID provocation tests and difficulties in the classification of children with nonsteroidal anti-inflammatory drug hypersensitivity

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used in children and can frequently cause hypersensitivity reactions. Rates of confirmed NSAID hypersensitivity (NSAID-H) in children are low.

OBJECTIVE

To evaluate the results of drug provocation tests (DPTs) with NSAIDs and to evaluate the difficulties encountered in the classification of NSAID-H in children.

METHODS

The study included patients with suspected NSAID-H who were examined in our clinic between January 1, 2015, and December 31, 2018. Oral provocation tests with NSAIDs were performed and reactions were classified according to the European Academy of Allergy and Clinical Immunology position paper on NSAID-H.

RESULTS

A total of 243 patients (57.2% male patients) presented with suspected NSAID-H during the study period. Of these, 168 patients (69.1%) had a history of reaction to ibuprofen. Isolated skin involvement was the most frequent symptom (86%). A total of 238 DPTs were performed with the suspected agents and 34 had positive results. The families of 12 patients refused provocation testing with the suspected agent or aspirin and these patients could not be diagnosed. Of the 231 patients, 47 patients (20.3%) received a diagnosis of NSAID-H. Twenty patients with NSAID-H could not be classified because their guardians did not consent to further testing with aspirin.

CONCLUSION

Performing diagnostic tests is important in patients with no contraindications. Characterizing these reactions in children can be difficult because of the coexistence of indistinguishable symptoms in their history and DPTs, as well as the need for multiple provocation tests. Therefore, further research is needed on this subject.

Progress in understanding hypersensitivity reactions to nonsteroidal anti-inflammatory drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs), the medications most commonly used for treating pain and inflammation, are the main triggers of drug hypersensitivity reactions. The latest classification of NSAIDs hypersensitivity by the European Academy of Allergy and Clinical Immunology (EAACI) differentiates between cross-hypersensitivity reactions (CRs), associated with COX-1 inhibition, and selective reactions, associated with immunological mechanisms. Three phenotypes fill into the first group: NSAIDs-exacerbated respiratory disease, NSAIDs-exacerbated cutaneous disease and NSAIDs-induced urticaria/angioedema. Two phenotypes fill into the second one: single-NSAID-induced urticaria/angioedema/anaphylaxis and single-NSAID-induced delayed reactions. Diagnosis of NSAIDs hypersensitivity is hampered by different factors, including the lack of validated in vitro biomarkers and the uselessness of skin tests. The advances achieved over recent years recommend a re-evaluation of the EAACI classification, as it does not consider other phenotypes such as blended reactions (coexistence of cutaneous and respiratory symptoms) or food-dependent NSAID-induced anaphylaxis. In addition, it does not regard the natural evolution of phenotypes and their potential interconversion, the development of tolerance over time or the role of atopy. Here, we address these topics. A state of the art on the underlying mechanisms and on the approaches for biomarkers discovery is also provided, including genetic studies and available information on transcriptomics and metabolomics.

A Multicenter Retrospective Study on Hypersensitivity Reactions to Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) in Children: A Report from the European Network on Drug Allergy (ENDA) Group

BACKGROUND

Diagnosis of hypersensitivity (HS) reactions to nonsteroidal anti-inflammatory drugs (NSAIDs) in children is complex. The real prevalence of NSAID HS remains unknown because a drug provocation test (DPT) is not always performed with the culprit NSAID.

OBJECTIVE

To describe and compare the diagnostic workup among different European centers and to find out the real proportion of NSAID HS by performing a DPT with the culprit drug.

METHODS

We retrospectively collected data from children (0-10 years) and adolescents (10-18 years) with a history of NSAID reactions and who underwent a complete allergy workup including DPTs with the culprit in 6 different pediatric centers: Belgrade, Florence, Geneva, Madrid, Porto, and Rome.

RESULTS

A total of 693 children with a history of NSAID reactions were enrolled, and a total of 526 DPTs were performed with the culprit NSAID. The diagnosis of NSAID HS was confirmed in 19.6% (103 of 526) of children by performing a DPT with the culprit drug. The major differences in the allergy workup among the 6 centers concerned the duration of the DPT and the practical use of skin tests for diagnosing NSAID HS. In addition, the use of acetyl salicylic acid to differentiate single reactor or cross-intolerance patients is not common, except in Spain.

CONCLUSION

The value of this study is that although different approaches are used around Europe to diagnose NSAID HS, we found that the percentage of confirmed NSAID HS is less than 20%. This highlights the importance of the DPT in confirming or excluding NSAID HS in the pediatric population.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several 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.

Two approaches for diagnosis of nonsteroidal anti-inflammatory drug hypersensitivity in children

BACKGROUND

The oral provocation test (OPT) with culprit drug is the gold standard in the diagnosis of nonsteroidal anti-inflammatory drug hypersensitivity (NSAID-H). Some authors have proposed that the total number of OPTs required to diagnose NSAID-H is much lower with acetyl salicylic acid (ASA) provocations, regardless of patients' reaction history, and less time consuming.

OBJECTIVE

This study aims to evaluate the total number of OPTs required to confirm NSAID-H according to the drugs (ASA or culprit NSAID) used in the initial OPT.

METHODS

The study included patients with a history of NSAID-H. Data on the demographic and clinical features, coexisting chronic or allergic disease, and laboratory results were collected from medical records. The drug used for the initial OPT (ASA or culprit NSAID), results of the OPT, and the total number of OPTs were reviewed.

RESULTS

We included 56 children with suspected hypersensitivity reaction to NSAIDs. NSAID-H was confirmed in 21 children (37.5%). We calculated that if all OPTs were performed with culprit drugs as an initial choice, the number of OPTs required for diagnosis would be 3 or more in 85.7% of positive cases. The number of episodes was an independent risk factor for NSAID-H by multiple logistic regression analysis (odds ratio, 4.3; 95% confidence interval, 1.48-12.24; P = .007).

CONCLUSION

Performing an initial OPT with ASA regardless of patients' reaction history can result in much lower numbers of OPT to diagnose NSAID-H and can improve patient compliance.

Recent developments in drug hypersensitivity in children

Introduction: Drug allergy is an important public health problem that causes 0.4-10.3% of hospital admissions in children. The epidemiology, clinical spectrum, diagnosis, and management of drug hypersensitivity reactions (DHRs) differ in pediatric and adult patients. However, the same algorithms used in adults have often been applied in the pediatric population due to a lack of evidence in the literature. Areas covered: In this review, we aimed to discuss recent developments in the area of pediatric DHRs based on the growing body of literature advancing our understanding of the epidemiology, clinical aspects, and diagnostic approaches to DHRs in children. Expert opinion: Misdiagnosis, under-diagnosis, and self-diagnosis are common problems related to drug allergies in children. Viral infections are particularly frequent in children and make diagnosis difficult. Identifying true DHR is a key step in the management of drug allergy in children. Therefore, a complete allergy work-up with standardized drug allergy tests is necessary. In order to eliminate non-standardized tests, future studies including larger numbers of children should be conducted to determine more accurate standardized tests for diagnosing DHRs in the pediatric population.

Pediatric Drug Hypersensitivity

PURPOSE OF REVIEW

Pediatric drug hypersensitivity is a rapidly evolving field. The purpose of this paper is to review the current state of pediatric drug hypersensitivity and highlight new developments in diagnosis and management.

RECENT FINDINGS

This paper will discuss the safety and use of risk stratification to proceed directly to oral challenge without prior skin testing for β-lactam reactions. We review unique aspects of pediatric drug challenges and desensitizations. It is important to accurately diagnose pediatric drug hypersensitivity reactions through a detailed history, physical examination, and available diagnostic testing. Understanding of the underlying mechanism leads to appropriate classification which is necessary to direct management. The decision to perform drug challenge, desensitization, or recommend avoidance of a medication can have a significant impact on a patient's treatment. Utilization of weight-based dose and infusion rate adjustments for current drug challenge and desensitization protocols optimize success.

Characteristics of NSAID-induced hypersensitivity reactions in childhood

Non-steroidal anti-inflammatory drugs (NSAIDs) are available as over-the-counter drugs, and they are commonly used in children for their antipyretic, analgesic, and anti-inflammatory effects. NSAIDs are among the most frequently reported drugs associated with hypersensitivity reactions and even with anaphylaxis. A complete evaluation of the patients based on reported clinical manifestations, timing of the reaction, the presence of underlying disease, and reactions to other NSAIDs allows clinicians to stratify children with a history of reaction to NSAIDs. Although NSAID-induced hypersensitivity reactions have mainly been investigated in adults, recent studies have aimed to explore their epidemiology in the pediatric population. This review will cover the current understanding of clinical manifestations, the risk factors, and the different phenotypes of NSAID-induced hypersensitivity reactions with a comprehensive overview of the epidemiologic data from past to present and the practical approach to the management of NSAID hypersensitivity in children and adolescents.

SIAIP position paper: provocation challenge to antibiotics and non-steroidal anti-inflammatory drugs in children

Drug hypersensitivity reactions (DHRs) in childhood are mainly caused by betalactam or non-betalactam antibiotics, and non-steroidal anti-inflammatory drugs (NSAIDs). Laboratory tests for identifying children who are allergic to drugs have low diagnostic accuracy and predictive value. The gold standard to diagnose DHR is represented by the drug provocation test (DPT), that aims of ascertaining the causative role of an allergen and evaluating the tolerance to the suspected drug. Different protocols through the administration of divided increasing doses have been postulated according to the type of drug and the onset of the reaction (immediate or non immediate reactions). DPT protocols differ in doses and time interval between doses. In this position paper, the Italian Pediatric Society for Allergy and Immunology provides a practical guide for provocation test to antibiotics and NSAIDs in children and adolescents.

NSAIDs-hypersensitivity often induces a blended reaction pattern involving multiple organs

Non-steroidal anti-inflammatory drugs (NSAIDs)-induced hypersensitivity reactions are classified by the European Network on Drug Allergy (ENDA) as either cross-reactive or selective. The former is the most frequent type and includes patients with exclusively respiratory symptoms (NSAIDs-exacerbated respiratory disease, NERD) or exclusively cutaneous symptoms: NSAIDs-induced urticaria/angioedema (NIUA); and NSAIDs-exacerbated cutaneous disease (NECD). However, although not reflected in the current classification scheme (ENDA), in clinical practice a combination of both skin and respiratory symptoms or even other organs such as gastrointestinal tract symptoms (mixed or blended reactions) is frequently observed. This entity has not been sufficiently characterised. Our aim was to clinically characterize blended reactions to NSAIDs, comparing their clinical features with NERD and NIUA. We evaluated patients with symptoms suggestive of hypersensitivity to NSAIDs who attended the Allergy Unit of the Regional University Hospital of Malaga (Malaga, Spain) between 2008 and 2015. We included 880 patients confirmed as cross-reactive based on clinical history, positive nasal provocation test with lysine acetylsalicylate (NPT-LASA), and/or positive drug provocation test (DPT) with acetylsalicylic acid (ASA), who were classified as blended (261; 29.6%), NERD (108; 12.3%) or NIUA (511; 58.1%). We compared symptoms, drugs, underlying diseases and diagnostic methods within and between groups. Among blended patients the most common sub-group comprised those developing urticaria/angioedema plus rhinitis/asthma (n = 138), who had a higher percentage of underlying rhinitis (p < 0.0001) and asthma (p < 0.0001) than NIUA patients, showing similarities to NERD. These differences were not found in the sub-group of blended patients who developed such respiratory symptoms as glottis oedema; these were more similar to NIUA. The percentage of positive NPT-LASA was similar for blended (77%) and NERD groups (78.7%). We conclude that blended reactions are hypersensitivity reactions to NSAIDs affecting at least two organs. In addition to classical skin and respiratory involvement, in our population a number of patients also develop gastrointestinal symptoms. Given the high rate of positive responses to NPT-LASA in NERD as well as blended reactions, we suggest that all patients reporting respiratory symptoms, regardless of whether they have other associated symptoms, should be initially evaluated using NPT-LASA, which poses less risk than DPT.

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.

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.

Natural evolution in patients with nonsteroidal anti-inflammatory drug-induced urticaria/angioedema

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most frequent triggers of drug hypersensitivity with NSAIDs-induced urticaria/angioedema (NIUA) the most common phenotype. Loss of hypersensitivity has been reported for IgE-mediated reactions; however, it has not been assessed in nonimmunological reactions such as NIUA. We evaluated NSAID-hypersensitivity over time in NIUA patients.

METHODS

Patients confirmed as NIUA by positive drug provocation test (DPT) with acetylsalicylic acid (ASA) during 2005-2012 (V1) were included (n=38). Subjects were prospectively re-evaluated by DPT with ASA/other NSAIDs at two time points between 2013 and 2015 (V2 and V3). Atopy was assessed by skin prick test (SPT) using inhalant and food allergens.

RESULTS

Patients were evaluated at V1 and re-evaluated after 60 months (V2; IR:48-81) and a further 18 months (V3; IR:14-24). At V2, the majority (24; 63.15%) tolerated ASA and other NSAIDs (Group A) while 14 (36.84%) still reacted (Group B). At V3, all Group A patients remained tolerant; all Group B patients remained hypersensitive. The number of previous episodes reported at V1 and the percentage of reactions induced by ASA/ibuprofen were significantly lower in Group A (P=.005 and P=.006, respectively). Group A patients developed tolerance 72 months (IR:45-87) after their last evaluated reaction (V1); this interval was shorter in nonatopics (P=.003), patients who experienced reactions over 1 hour after NSAIDs administration (P=.001), and those who experienced isolated urticaria after NSAID intake (P=.024).

CONCLUSIONS

NIUA patients may develop tolerance to NSAIDs over time, a process that seems to be influenced by atopy and type of clinical reaction.

Aspirin and Nonsteroidal Antiinflammatory Drugs Hypersensitivity and Management

Aspirin and nonsteroidal antiinflammatory drugs (NSAIDs) are widely used in the United States and throughout the world for a variety of indications. Several unique hypersensitivity syndromes exist to this class of medications, making them one of the common reasons for consultation to the allergist. The lack of any laboratory-based diagnostic studies to assist in identifying the culprits in these reactions make evaluation of aspirin and NSAID hypersensitivity challenging. Identifying patients appropriate for oral challenge and/or desensitization protocols is the standard pragmatic approach to this issue when it arises.

Pro and Contra: Provocation Tests in Drug Hypersensitivity

Drug provocation test (DPT) is the controlled administration of a drug to diagnose immune- or non-immune-mediated drug hypersensitivity and the last step for accurate recognition of drug hypersensitivity reactions when the previous diagnostic evaluations are negative or unavailable. A DPT is performed only if other conventional tests fail to yield conclusive results. In each clinical presentation, "to provoke or not to provoke" a patient should be decided after careful assessment of the risk-benefit ratio. Well-defined benefits of DPT include confirmative exclusion of diagnoses of drug hypersensitivity and provision of safe alternatives. However, disadvantages such as safety, difficulty in interpretations of results, lack of objective biomarkers, risks of resensitization, efficiency in daily practice, and lack of standardized protocols, are poorly debated. This review summarizes the current published research concerning DPT, with particular emphasis on the advantages and disadvantages of DPT in an evidence-based manner.

Discrepancies in the diagnosis and classification of nonsteroidal anti-inflammatory drug hypersensitivity reactions in children

BACKGROUND

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently encountered in daily clinical practice. The aim of this study was to determine the confirmation rates, risk factors of NSAID hypersensitivity in children and to try to classify them with a standardized diagnostic protocol.

METHODS

All patients with a suspicion of NSAID-induced hypersensitivity were evaluated with European Network for drug Allergy (ENDA) recommendations. The children were classified as selective responders (SRs) or cross-intolerant (CI) depending on the drug provocation test (DPT) results.

RESULTS

We evaluated 106 children with a suspicion of NSAID hypersensitivity. NSAID hypersensitivity was confirmed with tests in 31 patients; 4 (12.9%) were diagnosed by skin tests and 27 (87.1%) by DPTs and two patients with a history of anaphylaxis by medical records. Eleven patients (33.3%) were classified as SRs, whereas twenty-two (66.6%) children as CIs. SRs and CIs were further classified as NSAID-induced urticaria/angioedema (n = 8), NSAID-exacerbated cutaneous disease (n = 6) and NSAID-exacerbated respiratory disease (n = 1) and single NSAID-induced urticaria/angioedema and/or anaphylaxis (n = 11). Eight (24.2%) patients could not be categorized according to ENDA/GA²LEN classification; one CI patient could not be classified based on pathomechanisms, seven CIs could not be categorized based on the underlying disease and clinical manifestations. A reaction within an hour of drug intake (aOR:3.0, 95% confidence interval: 1.18-7.67, p = 0.021), a history with multiple NSAIDs hypersensitivity (aOR:2.9, 95% confidence interval: 1.16-7.60, p = 0.022), and family history of atopy (aOR:4.0, 95% confidence interval: 1.50-10.82, p = 0.006) were found as the independent risk factors related to confirmed NSAID hypersensitivity.

CONCLUSIONS

This study suggests the presence of different phenotypes which do not fit into the current classifications in children with NSAID hypersensitivity.

Copy number variation in ALOX5 and PTGER1 is associated with NSAIDs-induced urticaria and/or angioedema

OBJECTIVE

Cross-intolerance to NSAIDs is a class of drug hypersensitivity reaction, of which NSAIDs-induced urticaria and/or angioedema (NIUA) are the most frequent clinical entities. They are considered to involve dysregulation of the arachidonic acid pathway; however, this mechanism has not been confirmed for NIUA. In this work, we assessed copy number variations (CNVs) in eight of the main genes involved in the arachidonic acid pathway and their possible genetic association with NIUA.

MATERIALS AND METHODS

CNVs in ALOX5, LTC4S, PTGS1, PTGS2, PTGER1, PTGER2, PTGER3, and PTGER4 were analyzed using TaqMan copy number assays. Genotyping was carried out by real-time quantitative PCR. Individual genotypes were assigned using the CopyCaller Software. Statistical analysis was carried out using GraphPad prism 5, PLINK, EPIDAT, and R version 3.1.2.

RESULTS AND CONCLUSION

A total of 151 cases and 139 controls were analyzed during the discovery phase and 148 cases and 140 controls were used for replication. CNVs in open reading frames were found for ALOX5, PTGER1, PTGER3, and PTGER4. Statistically significant differences in the CNV frequency between NIUA and controls were found for ALOX5 (Pc=0.017) and PTGER1 (Pc=1.22E-04). This study represents the first analysis showing an association between CNVs in exonic regions of ALOX5 and PTGER1 and NIUA. This suggests a role of CNVs in this pathology that should be explored further.

Non-steroidal anti-inflammatory drug hypersensitivity in children

INTRODUCTION

There are rather few publications about hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAID) in the paediatric age. In this study, we aimed to assess the frequency of confirmed NSAID hypersensitivity in children with a previous reported reaction to NSAID in order to investigate the role of the drug provocation test (DPT) in the diagnostic workup and to explore the factors associated with confirmed NSAID hypersensitivity.

METHODS

We conducted a retrospective analysis of the clinical files from every patient under 18 years old who attended two Portuguese paediatric allergy outpatient clinics, from January 2009 to August 2014, due to a suspected NSAID hypersensitivity.

RESULTS

We included 119 patients, with a median age of nine years (P₂₅-P₇₅: 5-14). Ibuprofen was the commonest implicated NSAID in the patients' reports (n=94-79%). After DPT, NSAID hypersensitivity was confirmed in nine (7.6%) patients, excluded in 93 (78.2%) and was inconclusive in 17 (14.3%). In the majority (n=95-79.8%), the reaction occurred in the first 24h after intake. Eighty-four patients (70.6%) reported only cutaneous manifestations and 18 (15.1%) had systemic symptoms. Anaphylaxis represented a relative risk to NSAID hypersensitivity confirmation. No association was found for atopy and the number of previous reactions.

CONCLUSION

In our study, NSAID hypersensitivity was confirmed in a small proportion of the patients with a previous reported reaction. Ibuprofen was the most implicated drug with urticaria/angio-oedema as the commonest manifestation. Anaphylaxis was associated with confirmed drug hypersensitivity. The drug provocation test was essential to establish the diagnosis.

Phenotypical characterization of children with hypersensitivity reactions to NSAIDs

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) are the main cause of drug-induced hypersensitivity in children. Many classifications have been proposed, focusing on adults. So far, no large study has deeply investigated a pediatric cohort. The aim of the present study was to describe a population of NSAID hypersensitive patients reporting a reaction during their childhood and to verify whether it is possible to classify pediatric patients, following the EAACI/ENDA classification.

METHODS

We conducted a historical prospective study including patients evaluated from 1996 to 2015 in the allergy unit of the Montpellier University Hospital. We included 635 patients. For each patient, we recorded clinical manifestations and possible comorbidities and tried to identify possible risk factors.

RESULTS

NSAID hypersensitivity was diagnosed in 107 of 635 patients (16.9%). In this group, 43 patients (40.2%) could not be classified following the ENDA recommendations. The main discrepancies were on the patients' clinical manifestations and on their possible underlying diseases. We identified, on a multivariate analysis, some risk factors for NSAID hypersensitivity: chronic urticaria (OR 7.737, 3.375-18.296 95%CI), atopic status (OR 2.514, 1.504-4.364 95%CI), and allergic rhinoconjunctivitis (OR 1.799, 1.138-2.837 95%CI). On the basis of our results, we are proposing an adapted classification for NSAID hypersensitivity in children.

CONCLUSIONS

The current ENDA classification does not seem to be adapted for pediatric patients; a modified version does. Our study could help allergists better understand the differences between adults and children in developing hypersensitivity reactions to NSAIDs, but further large-scale prospective longitudinal analyses are required to validate this new classification.

Immediate and non-immediate allergic reactions to amoxicillin present a diagnostic dilemma: a case series

Background

Allergic reactions to amoxicillin are very common occurrences in the pediatric age group; however, onset of symptoms can present a diagnostic dilemma.

Case presentation

We present a case series that describes three children (8-year-old white girl, 2-year-old white boy and 14-month-old Chinese boy) who presented with varied onset of allergic reactions to amoxicillin, specifically immediate (within the first hour after exposure) and non-immediate onset. One child developed immediate onset allergy to oral challenge with amoxicillin although his clinical history was evident for non-immediate onset allergy to amoxicillin. He was the only case that had a positive skin test to penicillin. Two other children presented with reactions toward the end of their treatment course of amoxicillin, yet one patient developed immediate onset allergy while the other patient developed non-immediate onset allergy after challenge.

Conclusions

This case series demonstrates diagnostic challenges facing physicians assessing allergic reactions to amoxicillin. As onset of reactions can dictate severity and pathogenic type of allergy, a thorough clinical history and subsequent appropriate diagnostic testing including medication challenge can help establish the diagnosis.

[Hypersensitivity reactions to non-steroidal anti-inflammatory drugs and tolerance to alternative drugs]

INTRODUCTION

Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) are the most common reactions to drugs. The prevalence varies from 0.6 to 5.7% in general population, but there are no data available in children. The aim of this study is to determine the frequency of patients diagnosed with hypersensitivity to NSAIDs, and describe their clinical characteristics, type of hypersensitivity, and tolerance to alternative drugs.

METHODS

Retrospective study was conducted on children with suspected hypersensitivity to NSAIDs from January 2012 to December 2013. The diagnosis was confirmed by oral drug provocation test (DPT) to the drug involved in the group with a history of one episode, while in the group with a history of more than one episode with the same drug the diagnosis was based on clinical data. Subsequently, a DPT with acetylsalicylic acid (ASA) was done in order to classify hypersensitivity into selective or multiple. In those cases with a positive result, a DPT was performed with alternative drugs.

RESULTS

Out of a total of 93 children studied, 26 were diagnosed with hypersensitivity to NSAIDs: 7 confirmed by oral DPT, and 19 based on clinical data. Multiple hypersensitivity was diagnosed in 50% of patients. Ibuprofen was involved in all reactions. The most common clinical manifestation was angioedema (44%). Acetaminophen was the best tolerated alternative drug.

CONCLUSIONS

More than one quarter (28%) of the population studied was diagnosed with hypersensitivity to NSAIDs, and 50% had multiple hypersensitivity. Acetaminophen is a safe alternative in children with hypersensitivity to NSAIDs. Meloxicam may be an alternative in cases that do not tolerate acetaminophen.

Diagnostic evaluation and risk factors for drug allergies in children: from clinical history to skin and challenge tests

BACKGROUND

Parent or self-reported drug allergy claims frequently overestimate the real incidence of hypersensitivity reactions. A detailed and algorithmic diagnostic evaluation of drug reactions may allow a proper diagnosis.

OBJECTIVE

The aim of this study was to determine the confirmation rates and risk factors for confirmed allergic drug reactions in children.

SETTING

Mersin University Hospital in Turkey.

METHOD

The study consisted of children between ages of 8 months and 18 years with the history of suspected drug allergy as reported by the clinician or the patients. Parents were interviewed by a clinician to complete questionnaires that included questions about demographic data and characteristics of index drug reaction. Immediate reactions (IRs) were assessed with immediate-reading skin prick (SPT) and intradermal tests (IDT). Nonimmediate reactions (NIRs) were assessed with SPT, both early and delayed reading of IDT and patch tests. In case of negative skin tests, drug provocation tests were performed. The possible risk factors for confirmed drug allergy in univariate analysis (p < 0.1) were entered into the multivariate logistic regression analysis to determine independent predictors.

MAIN OUTCOME MEASURE

(1) Confirmation rates of drug allergy (2) Risk factors related to confirmed drug allergy in children.

RESULTS

We evaluated a total of 180 suspected drug allergy reactions in 97 children, mainly to antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs) and anticonvulsants. Among all suspected allergic drug reactions, 97 (53.9 %) were immediate type and 83 (46.1 %) were non-immediate type. The average time interval between the reaction and allergologic work-up was 5 months. Drug allergy confirmation rates were 30.1 % for beta-lactams, 27.2 % for non-betalactams, 21.1 % for NSAIDs and 30 % for anticonvulsants. Eight of 54 confirmed NIRs showed positivity on immediate skin tests. Regulatory T cells, TGF-β and IL-10 levels were not different between groups with and without confirmed drug allergy. A strong family and personal history of drug allergy were found to be significantly related to the confirmed allergic drug reactions.

CONCLUSION

Parent or self-reported drug allergy should be evaluated with a standardized diagnostic work-up before strict prohibitions are made. In addition, family and personal histories of drug allergy were significant risk factors related to allergic drug reactions in children.

Nonsteroidal anti-inflammatory drugs-exacerbated respiratory disease in adolescents

BACKGROUND

There has been no study investigating nonsteroidal anti-inflammatory drugs (NSAIDs)-exacerbated respiratory disease (NERD) exclusively in childhood. Therefore, in the current study, the authors aimed to evaluate the diagnostic features, clinical characteristics, and follow-up of adolescents diagnosed with NERD.

METHODS

The patients who were consecutively diagnosed with NERD between January 2011, and November 2013, included in the study. Oral provocation test (OPT) with at least 2 different NSAIDs was used to confirm NSAID hypersensitivity in patients with underlying asthma/chronic rhinosinusitis/nasal polyps. All patients were followed regularly in 3-month intervals by the Pediatric Allergy and Otorhinolaryngology Department for asthma, allergic rhinitis, or chronic rhinosinusitis with or without nasal polyps.

RESULTS

A total of 10 adolescents with NERD were included in the study. The mean age of the patients at the time of diagnosis was 14.9 ± 1.5 years. Hives or angioedema accompanied respiratory complaints induced by NSAIDs. The mean duration of follow-up was 28.9 ± 12.4 months. All patients had asthma except 1 with asymptomatic bronchial hyperreactivity. Asthma of patients was well-controlled with moderate dose of inhaled corticosteroids. Chronic rhinosinusitis with or without nasal polyps developed in 2 patients. Aspirin desensitization was required in these 2 patients with recurrent nasal polyps.

CONCLUSION

NERD in childhood has much more favorable clinical characteristics and course than in adulthood. Few adolescents with NERD refer with typical chronic upper respiratory tract complaints. The asthma component seems to be mild and is well controlled in the short-term follow-up.

Challenge-proven aspirin hypersensitivity in children with chronic spontaneous urticaria

BACKGROUND

Nonsteroidal anti-inflammatory drug (NSAID) exacerbated cutaneous disease is defined as the exacerbation of wheals and/or angioedema in patients with a history of chronic spontaneous urticaria (CSU). The objective of this study was to define 'aspirin-hypersensitive' children and adolescents in a clearly defined group of patients with CSU and to describe their clinical features.

METHODS

Eighty-one children with a history of CSU were enrolled over a 3-year period. The daily or almost daily (>4 days a week) presence of urticaria was defined as 'chronic persistent urticaria' (CPU), while the presence of urticaria for 2-4 days a week was defined as 'chronic recurrent urticaria' (CRU). Single-blind, placebo-controlled provocation tests (SBPCPTs) with aspirin were performed for children with CSU.

RESULTS

Patients with CRU had a longer duration of cutaneous symptoms [1.6 (0.5-4) vs 0.6 (0.3-1.5) years], and stress was less frequently experienced as an eliciting factor in patients with CRU compared with the patients with CPU (P < 0.016, P = 0.024, respectively). SBPCPTs with aspirin revealed that 14 of 58 patients (24%) with CPU and one of 10 patients with CRU (10%) were aspirin hypersensitive. Aspirin hypersensitivity rate was 26.5% in patients <12 years of age. All of the 15 aspirin-hypersensitive patients (aged between 6.6 and 17.4 years), except for three, experienced an unequivocal angioedema of the lips as a positive reaction in SBPCPT.

CONCLUSIONS

Nearly a quarter of children and adolescents with CSU were hypersensitive to aspirin. For children with chronic urticaria, determination of NSAID hypersensitivity in a well-controlled clinical setting will help to avoid severe drug hypersensitivity reactions.

Tolerance to etoricoxib in children with nonsteroidal anti-inflammatory drug hypersensitivity

Background

Cyclooxygenase-2 (COX-2) inhibitors have been found to be safe alternatives in adults with cross-intolerant hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs). However they are usually not prescribed in children and there is little information about their tolerance in the pediatric age group.

Objective

This study aims to evaluate the tolerance to etoricoxib in children with hypersensitivity to multiple antipyretics.

Methods

A retrospective case series of children diagnosed with hypersensitivity reactions to NSAIDs and/or paracetamol who underwent a drug provocation test (DPT) with etoricoxib. Information on atopy, family history of allergic diseases, and medication usage was collected. Outcomes of the DPTs and tolerance to etoricoxib were also evaluated.

Results

A total of 24 children, mean age 13.5 years, had a diagnosis of cross-intolerant hypersensitivity to NSAIDs and/or paracetamol. All except one patient successfully tolerated an oral challenge with etoricoxib. Of those who passed the DPT, the majority continued to use etoricoxib with no problems. It was found to be moderately effective in reducing fever and pain.

Conclusion

Etoricoxib can be used as a safe alternative in older children with hypersensitivity to multiple antipyretics.

Tolerance to COX-2 inhibitors in children with hypersensitivity to nonsteroidal anti-inflammatory drugs

BACKGROUND

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) can affect children, with the mechanism proposed being inhibition of the cyclooxygenase enzyme-1 (COX-1). In these patients nonchemically related NSAIDs, including COX-2 inhibitors, can induce the reaction, hampering treatment of fever and inflammatory processes.

OBJECTIVES

To analyse retrospectively tolerance to etoricoxib, a selective COX-2 inhibitor, and to meloxicam, a preferential COX-2 inhibitor, in children with hypersensitivity to NSAIDs.

METHODS

Clinical records of children (aged 1-14 years) diagnosed with hypersensitivity reactions to NSAIDs from January 2006 to January 2013 were included. The diagnosis was confirmed by oral drug provocation test (DPT) with the culprit NSAIDs and acetylsalicylic acid (ASA). Tolerance to paracetamol, etoricoxib and meloxicam was also evaluated.

RESULTS

The study included 41 children with a positive DPT with ASA and the culprit NSAID. DPT with paracetamol and etoricoxib was negative in all children, although two (4.9%) children developed a reaction after the administration of meloxicam.

CONCLUSIONS

These data indicate that both etoricoxib and meloxicam are good alternatives for treatment in older children with hypersensitivity to NSAIDs.