NSAID hypersensitivity (respiratory, cutaneous, and generalized anaphylactic symptoms)

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.

Lack of Major Involvement of Common CYP2C Gene Polymorphisms in the Risk of Developing Cross-Hypersensitivity to NSAIDs

Cross-hypersensitivity to non-steroidal anti-inflammatory drugs (NSAIDs) is a relatively common, non-allergic, adverse drug event triggered by two or more chemically unrelated NSAIDs. Current evidence point to COX-1 inhibition as one of the main factors in its etiopathogenesis. Evidence also suggests that the risk is dose-dependent. Therefore it could be speculated that individuals with impaired NSAID biodisposition might be at increased risk of developing cross-hypersensitivity to NSAIDs. We analyzed common functional gene variants for CYP2C8, CYP2C9, and CYP2C19 in a large cohort composed of 499 patients with cross-hypersensitivity to NSAIDs and 624 healthy individuals who tolerated NSAIDs. Patients were analyzed as a whole group and subdivided in three groups according to the main enzymes involved in the metabolism of the culprit drugs as follows: CYP2C9, aceclofenac, indomethacin, naproxen, piroxicam, meloxicam, lornoxicam, and celecoxib; CYP2C8 plus CYP2C9, ibuprofen and diclofenac; CYP2C19 plus CYP2C9, metamizole. Genotype calls ranged from 94 to 99%. No statistically significant differences between patients and controls were identified in this study, either for allele frequencies, diplotypes, or inferred phenotypes. After patient stratification according to the enzymes involved in the metabolism of the culprit drugs, or according to the clinical presentation of the hypersensitivity reaction, we identified weak significant associations of a lower frequency (as compared to that of control subjects) of CYP2C8*3/*3 genotypes in patients receiving NSAIDs that are predominantly CYP2C9 substrates, and in patients with NSAIDs-exacerbated cutaneous disease. However, these associations lost significance after False Discovery Rate correction for multiple comparisons. Taking together these findings and the statistical power of this cohort, we conclude that there is no evidence of a major implication of the major functional CYP2C polymorphisms analyzed in this study and the risk of developing cross-hypersensitivity to NSAIDs. This argues against the hypothesis of a dose-dependent COX-1 inhibition as the main underlying mechanism for this adverse drug event and suggests that pre-emptive genotyping aiming at drug selection should have a low practical utility for cross-hypersensitivity to NSAIDs.

Clinical Characterization of Patients with Chronic Spontaneous Urticaria according to Anti-TPO IgE Levels

Background

Chronic spontaneous urticaria (CSU) is a heterogeneous disease with some frequent comorbidities like autoimmune diseases, drug reactions, and inducible urticaria. IgE antibodies against thyroid peroxidase (anti-TPO IgE) could be associated with some of these clinical characteristics.

Objective

To explore the clinical characteristics of CSU patients, according to the presence of anti-TPO IgE in serum.

Methods

Anti-TPO IgE levels were measured during the clinical control period (Urticaria Activity Score, 0 point) and exacerbation period (≥3 points) in 100 CSU patients. Patients with self-reported exacerbation of skin involvement by foods, nonsteroidal anti-inflammatory drugs (NSAIDs), and physical triggers underwent controlled challenge tests.

Results

We identified 2 groups of patients: (1) patients with anti-TPO IgE during the clinical control period or during an exacerbation, who had a higher frequency of atopy, asthma, and positive challenge test results with NSAIDs and (2) patients without anti-TPO IgE during any period, who had a higher frequency of positive challenge test results for inducible urticaria. Among the first group (anti-TPO IgE at any point), we identified 3 subgroups: patients with anti-TPO IgE during the clinical control period (n = 12); patients with anti-TPO IgE during the clinical control period and significantly increased levels during an urticaria exacerbation (n = 18); and patients with anti-TPO IgE only during an exacerbation (n = 13). None of the patients with self-reported food reactions had a positive challenge test result.

Conclusion

Anti-TPO IgE is a useful biomarker for differentiating between clinical phenotypes of patients with CSU. Elevation of anti-TPO IgE during exacerbation periods supports an association between this autoantibody and the pathogenesis of urticaria.

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.

Physiopathology and genetics in aspirin-exacerbated respiratory disease

INTRODUCTION

Aspirin-exacerbated respiratory disease (AERD) is a clinical entity characterized by hypersensitivity to aspirin leading to asthma and chronic rhinosinusitis with nasosinusal polyposis. The pathophysiology of the disease involves disruption at the level of arachidonic acid metabolism. Therefore, genetic association studies have been focused on the genes coding this pathway. As other mechanisms involved in the genesis of the disease were elucidated, the corresponding genes were also explored.

AIM

To describe the association reported in the literature between gene polymorphisms involved in the pathophysiology or therapeutic processes of AERD.

RESULTS

There is a genetic association between polymorphisms of genes involved in the synthesis of proteins related to arachidonic acid metabolism (LTC4S, ALOX5), antigen presentation (HLA), inflammation (IL5, IL17), and aspirin metabolism (CYP2C19).

CONCLUSIONS

Genetic association research in AERD has evaluated studies of SNPs in metabolic pathways related to arachidonic acid. Recently, whole genome analysis strategies have allowed the detection of new genetic variants that were previously not considered. Furthermore, these studies have identified SNPs that are associated with inflammatory processes, which could serve as diagnostic markers or predictors of the therapeutic response.

Polymorphism of IL10, IL4, CTLA4, and DAO Genes in Cross-Reactive Nonsteroidal Anti-inflammatory Drug Hypersensitivity

Our aim was to evaluate genetic polymorphism of molecules involved in immunoregulatory/allergic processes in patients who presented with cutaneous hypersensitivity caused by chemically unrelated nonsteroidal anti-inflammatory drugs. Polymorphisms at IL10 (-1082 G>A), IL4 (-589 C>T), CTLA4 (+49A>G), and DAO (+8956 C>G) genes were studied in 55 cases and 97 controls by the polymerase chain reaction-restriction fragment length polymorphism technique. With regard to the polymorphism at IL10 -1082, higher frequencies of the AG genotype (57% vs 39%) and G allele carriers (70% vs 48%) were found among the patients, indicating a risk effect (odds ratio [OR] = 2.56 and P = .01 for AG genotype and OR = 2.52; P = .01 for AG/GG). For the CTLA4 +49 A/G single-nucleotide polymorphism (SNP), AG genotype (31.0%) (P = .02) and G carrier (54.0%) (P = .05) frequencies were found to be significantly lower in the patient group compared with the control group (51.0% and 69.0%, respectively). The SNP DAO +8956 C>G was associated with a strong protective effect, with OR values of 0.83 for CG and 0.11 for GG genotype (P = .04 for the codominant model), suggesting an allele dose effect. The combination of IL10 and DAO SNPs in a multivariate model did not alter the OR values, suggesting independent effects for both SNPs. The results are striking. In conclusion, these results suggest that polymorphisms in regulatory targets of the immune response and in DAO gene could modulate an individual's susceptibility to nonsteroidal anti-inflammatory drug hypersensitivity reactions. Further studies will be necessary to complement our results.

Adverse Drug Reactions in Children: The Double-Edged Sword of Therapeutics

Adverse drug reactions (ADRs) represent a major health problem worldwide, with high morbidity and mortality rates. ADRs are classified into Type A (augmented) and Type B (bizarre) ADRs, with the former group being more common and the latter less common but often severe and clinically more problematic due to their unpredictable nature and occurrence at any dose. Pediatric populations are especially vulnerable to ADRs due to the lack of data for this age group from the drug development process and because of the wide use of off-label and unlicensed use of drugs. Children are more prone to specific types of ADRs because of the level of maturity of body systems involved in absorption, metabolism, transportation, and elimination of drugs. This state-of-the-art review provides an overview of definitions, classifications, epidemiology, and pathophysiology of ADRs and discusses the available evidence for related risk factors and causes of ADRs in the pediatric population.

Pharmacogenomics of off-target adverse drug reactions

Off-target adverse drug reactions (ADRs) are associated with significant morbidity and costs to the healthcare system, and their occurrence is not predictable based on the known pharmacological action of the drug's therapeutic effect. Off-target ADRs may or may not be associated with immunological memory, although they can manifest with a variety of shared clinical features, including maculopapular exanthema, severe cutaneous adverse reactions (SCARs), angioedema, pruritus and bronchospasm. Discovery of specific genes associated with a particular ADR phenotype is a foundational component of clinical translation into screening programmes for their prevention. In this review, genetic associations of off-target drug-induced ADRs that have a clinical phenotype suggestive of an immunologically mediated process and their mechanisms are highlighted. A significant proportion of these reactions lack immunological memory and current data are informative for these ADRs with regard to disease pathophysiology, therapeutic targets and biomarkers which may identify patients at greatest risk. Although many serious delayed immune-mediated (IM)-ADRs show strong human leukocyte antigen associations, only a small subset have successfully been implemented in screening programmes. More recently, other factors, such as drug metabolism, have been shown to contribute to the risk of the IM-ADR. In the future, pharmacogenomic targets and an understanding of how they interact with drugs to cause ADRs will be applied to drug design and preclinical testing, and this will allow selection of optimal therapy to improve patient safety.

Demographic and clinical profiles in patients with acute urticaria

BACKGROUND

Urticaria is a common cause for consultation in general and specialised medical practices. There is scarce information on the characteristics of patients suffering acute urticaria in Latin America.

OBJECTIVES

To investigate demographic and clinical features of patients with acute urticaria attending two allergy clinics in Caracas, Venezuela.

METHODS

A prospective study of all new patients who consulted during a three-year period because of acute urticaria. Information on age, gender, symptom duration, previous medical history, body distribution of wheals and angio-oedema, laboratory investigations, skin prick tests, and pharmacological treatment, was collected. Patients were classified according to their age as children/adolescents and adults.

RESULTS

Two hundred and forty eight patients (177 adults and 71 children) were studied. Acute urticaria was more frequent in middle-aged atopic female patients. Lesions more often involved upper and lower limbs and head, and 31% of patients exhibited generalised urticaria. Laboratory investigations, performed only in selected cases, did not contribute to the final diagnosis. Most frequent subtypes of acute urticaria were spontaneous, dermographic, papular, and drug-induced urticaria. Most patients were treated with non-sedating antihistamines, with increased use of cetirizine and levocetirizine in children, while 5.6% of children and 20.3% of adults required the addition of short courses of systemic corticosteroids.

CONCLUSIONS

Acute urticaria is a frequent cause of consultation for allergists, affecting more often middle-aged female atopic patients. The use of extensive complementary tests does not seem to be cost-effective for this clinical condition. Spontaneous, dermographic, papular and drug-induced urticaria are the most common subtypes.

Aspirin-exacerbated cutaneous disease (AECD) is a distinct subphenotype of chronic spontaneous urticaria

BACKGROUND

A subset of patients with chronic spontaneous urticaria (CSU) experience disease exacerbations after receiving non-steroidal anti-inflammatory drugs (NSAIDs). This condition has been designated as Aspirin-Exacerbated Cutaneous Disease (AECD).

OBJECTIVES

The purpose of this study was twofold: (i) Investigate the demographic and clinical features of patients affected by AECD; (ii) To compare patients with AECD and NSAID-tolerant CSU patients for those characteristics.

METHODS

Patients with AECD and a group of unselected CSU patients tolerant to NSAIDs were studied. Demographic and clinical data were obtained by direct questioning and physical examination. Laboratory investigations and allergen skin prick tests were performed only in selected patients, as guided by the medical history.

RESULTS

Of 423 CSU patients admitted in the clinics, 52 (12.2%) had AECD. Compared with NSAID-tolerant CSU patients, AECD patients had significantly longer disease duration (57.7 ± 118.4 vs. 24.4 ± 36.6 months, P < 0.05), higher prevalence of angio-oedema (72.7 vs. 30.9%, P < 0.05) and atopy (83.8% vs. 58.4%, P < 0.05) and more frequent involvement of the face and upper respiratory tract (54.5% vs. 29.6%, P < 0.05).

CONCLUSIONS

AECD is a distinct phenotype that should be considered for inclusion as a separate subtype of chronic spontaneous urticaria.

Absorption, distribution, metabolism and excretion of loxoprofen after dermal application of loxoprofen gel to rats

1. Loxoprofen (LX), is a prodrug of the pharmacologically active form, trans-alcohol metabolite (trans-OH form), which shows very potent analgesic effect. In this study, the pharmacokinetics and metabolism of [(14)C]LX-derived radioactivity after dermal application of [(14)C]LX gel (LX-G) to rats were evaluated. 2. The area under concentration-time curve (AUC0-∞) of radioactivity in the plasma after the dermal application was 13.6% of that of the oral administration (p < 0.05). 3. After the dermal application, the radioactivity remained in the skin and skeletal muscle at the treated site for 168 h, whereas the AUC0-168 h of the radioactivity concentration in every tissue examined except the treated site was statistically lower than that after the oral administration (p < 0.05). 4. The trans-OH form was observed at high levels in the treated skin site at 0.5 h. Metabolite profiles in plasma, non-treated skin site and urine after the dermal application were comparable with those after the oral administration. 5. Renal excretion was the main route of elimination after the dermal application. 6. In conclusion, compared to the oral administration, the dermal application of [(14)C]LX-G showed lower systemic and tissue exposure with higher exposure in the therapeutic target site. The radioactivity revealed similar metabolite profiles in both administration routes.

NSAID-induced urticaria/angioedema does not evolve into chronic urticaria: a 12-year follow-up study

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most frequent medicaments involved in drug hypersensitivity reactions, with NSAID-induced urticaria/angioedema (NIUA) being the most frequent clinical entity. The natural evolution of NIUA has been suggested to lead to chronic urticaria (CU) in an important proportion of patients, such that NIUA may therefore precede CU. Our aim was to verify whether these entities are related by following up a large cohort of patients with NIUA as well as a control group over a long period of time.

METHODS

The study comprised three groups: (i) patients with a confirmed history of NIUA (more than two episodes with at least two different NSAIDs or positive drug provocation tests), (ii) patients with more than two episodes of urticaria/angioedema to a single NSAID with good tolerance to a strong COX-1 inhibitor and/or evidence by in vivo tests supporting specific IgE antibodies to the drug (single NSAID-induced urticaria/angioedema, SNIUA), and (iii) controls who tolerated NSAIDs. All cases in the three groups were followed up over a period of 12 years.

RESULTS

There were 190 patients with NIUA (64.6% female; mean age 43.71 ± 15.82 years, 110 with SNIUA, and 152 controls. At the 12-year evaluation, 12 patients with NIUA (6.15%) had developed CU over a 1- to 8-year period. Similar proportions were seen in SNIUA and controls.

CONCLUSIONS

Nonsteroidal anti-inflammatory drugs-induced urticaria/angioedema does not seem to precede the onset of CU over the medium term. Further research including a longer follow-up is necessary to verify this observation.

Nasal lysine aspirin challenge in the diagnosis of aspirin - exacerbated respiratory disease: asthma and rhinitis

BACKGROUND

Aspirin-exacerbated respiratory disease is under-diagnosed and therefore effective and inexpensive therapy with aspirin desensitization is rarely performed.

METHODS

We present an audit of 150 patients with difficult to treat nasal polyposis, 132 of whom also had asthma, 131 of whom underwent challenge with the only soluble form of aspirin, lysine aspirin (LAS), to confirm or exclude the diagnosis of aspirin-exacerbated respiratory disease (AERD).

RESULTS

One hundred patients proved positive on nasal challenge, 31 who were negative went onto oral LAS challenge and a further 14 gave positive results, leaving 17 who were negative to a dose equivalent to over 375 mg of aspirin. Nineteen were not challenged because of contraindications. With the exception of one patient who developed facial angioedema and two patients with > 20% drop in FEV1 (following nasal plus oral challenge) no other severe adverse events occurred. No hospitalization was required for these three patients. Nasal inspiratory peak flow monitoring was less sensitive to obstruction caused by aspirin than was acoustic rhinometry - which should be employed when aspirin challenge is an outpatient procedure.

CONCLUSIONS

Provided patients are carefully chosen and monitored LAS challenge is suitable for ENT day case practice where respiratory physician help with asthma is available and should reduce the under-diagnosis of this condition.

Design, synthesis and structure-activity relationship studies of novel and diverse cyclooxygenase-2 inhibitors as anti-inflammatory drugs

Because of the pivotal role of cyclooxygenase (COX) in the inflammatory processes, non-steroidal anti-inflammatory drugs (NSAIDs) that suppress COX activities have been used clinically for the treatment of inflammatory diseases/syndromes; however, traditional NSAIDs exhibit serious side-effects such as gastrointestinal damage and hyper sensitivity owing to their COX-1 inhibition. Also, COX-2 inhibition-derived suppressive or preventive effects against initiation/proliferation/invasion/motility/recurrence/metastasis of various cancers/tumours such as colon, gastric, skin, lung, liver, pancreas, breast, prostate, cervical and ovarian cancers are significant. In this study, design, synthesis and structure-activity relationship (SAR) of various novel {2-[(2-, 3- and/or 4-substituted)-benzoyl, (bicyclic heterocycloalkanophenyl)carbonyl or cycloalkanecarbonyl]-(5- or 6-substituted)-1H-indol-3-yl}acetic acid analogues were investigated to seek and identify various chemotypes of potent and selective COX-2 inhibitors for the treatment of inflammatory diseases, resulting in the discovery of orally potent agents in the peripheral-inflammation model rats. The SARs and physicochemical properties for the analogues are described as significant findings. For graphical abstract: see Supplementary Material. ( www.informahealthcare.com/enz ).

Molecular genetic mechanisms of chronic urticaria

Chronic urticaria (CU) is a common allergic skin disease that requires long-term pharmacological treatment. Some patients with severe CU suffer a poor quality of life. Although the pathogenic mechanisms of CU are not clearly understood, several groups have suggested that genetic mechanisms are involved in various CU cohorts. To further understand the molecular genetic mechanisms of CU, we summarize recent genetic data in this review. Although a few HLA alleles were suggested to be candidate markers in different ethnic groups, further replication studies that apply the recent classification are needed. Genetic polymorphisms in histamine-related genes, including FcεRI and HNMT, were suggested to be involved in mast cell activation and histamine metabolism. Several genetic polymorphisms of leukotriene-related genes, such as ALOX5, LTC4S, and the PGE2 receptor gene PTGER4, were suggested to be involved in leukotriene overproduction, a pathogenic mechanism. Further investigations using candidate gene approaches and genome-wide association studies (GWAS) will provide new insights into the molecular genetic mechanisms of CU, which will provide new marker genes for differentiation of CU phenotypes and identification of potential therapeutic targets.

Mediator release after nasal aspirin provocation supports different phenotypes in subjects with hypersensitivity reactions to NSAIDs

BACKGROUND

Multiple NSAID-induced urticaria/angioedema (MNSAID-UA) is an entity well differentiated from aspirin-exacerbated respiratory disease (AERD), although no detailed phenotype analysis has yet been performed. The objective was to evaluate the functional characteristics of MNSAID-UA subjects by analyzing the response to nasal lysine-aspirin challenge and measurement of nasal inflammatory mediator release compared with AERD subjects and controls.

METHODS

The study included 85 subjects with confirmed hypersensitivity to NSAIDs (≥3 episodes with >2 different NSAIDs or positive drug provocation) with either cutaneous (MNSAID-UA, n = 25) or respiratory manifestations (AERD, n = 60) and 30 tolerant controls (15 aspirin-tolerant asthmatic patients and 15 healthy controls). Nasal lavages at 0, 15, 60, and 120 min after lysine-aspirin challenge were analyzed for ECP, tryptase, PGE2 , PGD2 , LTD4 , and LTE4 .

RESULTS

Lysine nasal challenge was positive in 80% of the AERD cases but positive only in 12% of the MNSAID-UA group. MNSAID-UA subjects showed no changes in nasal ECP, whereas subjects with AERD had increased levels of ECP, with the highest peak at 15 min after challenge (P < 0.05). Tryptase levels were higher in AERD compared with MNSAID-UA and controls with the highest release of tryptase at 60 min (P < 0.05). Significant increases in PGD2 , LTD4 , and LTE4 were observed in AERD (at 60 min for PGD2 , LTD4 , and LTE4 ) but not in MNSAID-UA or control subjects (P < 0.05).

CONCLUSIONS

Data support the observation that MNSAID-UA, although sharing a common response with AERD to COX inhibitors, seems to have a distinctive phenotype, based on the response to nasal challenge and the release of inflammatory mediators.

Value of the clinical history in the diagnosis of urticaria/angioedema induced by NSAIDs with cross-intolerance

BACKGROUND

Multiple Non-steroidal anti-inflammatory drugs (NSAID)-induced urticaria/angioedema is the most common manifestation of hypersensitivity reactions to NSAIDs. Diagnostic evaluation is based on the clinical history and a drug provocation test.

OBJECTIVE

To evaluate the role of the clinical history in the diagnosis of multiple NSAID-induced urticaria/angioedema.

METHODS

We studied a group of patients with an unequivocal history of urticaria and/or angioedema after NSAID intake. Subjects had to have had at least two episodes of cutaneous symptoms with two different COX-1 inhibitors. The diagnosis was confirmed in all cases by a drug provocation test with acetyl salicylic acid (ASA). Multivariate analysis was done by analysing different variables, including number of drugs involved, episodes and time elapsed between drug intake and symptom onset.

RESULTS

Of the total group of 75 cases with multiple NSAID-induced urticaria/angioedema diagnosed according to the clinical history, 76% developed a positive drug provocation test with ASA. The risk for having hypersensitivity was 17 times higher in patients who developed symptoms within the first 60 min after drug intake, 13 times higher in those who experienced reactions with more than two non-chemically related NSAIDs, and 10 times higher in women.

CONCLUSIONS

Drug provocation testing with ASA confirms the diagnosis of multiple NSAID-induced urticaria/angioedema in up to 92% of cases with an unequivocal clinical history, when reactions occur within 1 h and more than two different NSAIDs are involved.

The general characteristics of acute urticaria attacks and the factors predictive of progression to chronic urticaria

BACKGROUND

The natural history of progression from acute urticaria (AU) to chronic urticaria (CU) remains poorly understood. This study aimed to investigate the potential triggers of AU attacks and factors associated with their duration, as well as the factors which may be predictive of progression to CU.

METHODS

The study included 281 AU patients (AU group). Data were obtained from 207 AU patients retrospectively and from 74 AU patients prospectively. The CU group consisted of 953 patients, whose data were previously published.

RESULTS

According to the medical history, the most common potential triggers of AU attacks were drugs (38.1%); infections (35.2%); stress (24.7%); and foods (17.8%). Attack duration was shorter in cases in which food (p=0.04) or infection (p=0.04) was the suspected trigger. Patients with a history of rhinitis (p=0.04) and food allergy (p=0.04), and positive skin prick test results for pollens (p=0.02) and dog (p=0.02) also had attacks of shorter duration. Patients with asthma had attacks of longer duration (p=0.01). Based on history and/or provocation test results, the prevalence of non-steroidal anti-inflammatory drug hypersensitivity (NSAIDH) was significantly higher in the CU group than the AU group (24.9% vs. 4.3%, respectively, (p<0.01)), as was antibiotic hypersensitivity (10.6% vs. 4.6%, respectively, (p<0.01)) and food allergy (18.3% vs. 3.9%, respectively, (p<0.01)).

NSAIDH (OR

7.97; 95%CI: 4.33-14.66; p<0.01) and food allergy (OR: 5.17; 95%CI: 2.71-9.85; p<0.01) were observed to be independent factors associated with CU.

CONCLUSIONS

As NSAIDH and food allergy were associated with CU, their presence should be carefully evaluated in patients with AU in order to predict progression to CU.

Nonallergic drug hypersensitivity reactions

BACKGROUND

Nonallergic drug hypersensitivities, also referred to as pseudoallergic or anaphylactoid reactions, have clinical manifestations that are often indistinguishable from allergic reactions.

METHODS

We performed a PubMed search using the terms 'drug allergy, drug hypersensitivity, pseudoallergies, anaphylaxis and nonallergic drug reactions' and reviewed 511 publications dated between 1970 and 2012. A total of 160 papers that were relevant to the most common nonallergic drug hypersensitivity reactions were selected for discussion.

RESULTS

Nonallergic drug hypersensitivities do not involve either IgE-mediated (type 1) or delayed (type 4) hypersensitivity. Nonallergic hypersensitivities are commonly referred to as pseudoallergic or idiosyncratic reactions. The common nonallergic drug hypersensitivities are secondary to chemotherapeutic drugs, radiocontrast agents, vancomycin, nonsteroidal anti-inflammatory agents, local anesthetic reactions and opiates. Protocols for skin testing of radiocontrast, nonsteroidal anti-inflammatory agents, local anesthetics and chemotherapeutic agents have been developed, though most have not been validated or standardized. Other diagnostic tests include in vitro-specific IgE tests, and the current 'gold' standard is usually an oral challenge or bronchoprovocation test. In the case of aspirin, even though it is not believed to be IgE-mediated, a 'desensitization' protocol has been developed and utilized successfully, although the mechanism of this desensitization is unclear.

CONCLUSIONS

Diagnostic methods exist to distinguish allergic from nonallergic drug hypersensitivity reactions. The best option in nonallergic drug hypersensitivity is avoidance. If that is not possible, premedication protocols have been developed, although the success of premedication varies amongst drugs and patients.

How can we better classify NSAID hypersensitivity reactions?--validation from a large database

BACKGROUND

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) is one of the most common drug hypersensitivities. Several clinical subtypes have been distinguished depending on symptomatology (respiratory, cutaneous, anaphylaxis), timing (immediate, delayed), underlying chronic disease (asthma, chronic urticaria) or putative mechanism of the reaction (allergic, nonallergic mediated). The aim of the present study was to better classify the many hypersensitivity reactions to NSAIDs.

METHODS

In the present retrospective study, during an 11-year study period, we collected data from all patients with a proven NSAID hypersensitivity. Reactions were classified according to clinical patterns, chronology, underlying diseases and the results of oral provocation tests into 5 and 7 groups in line with two published classifications, respectively.

RESULTS

Forty-nine and 88 out of 307 reactions (in 122 patients) could not be classified on the basis of the two previously published classifications. We created a new classification which could include all patient reactions.

CONCLUSIONS

Our new classification is more suitable for clinical expression of NSAID hypersensitivity. It allows clinicians to identify patients at a high risk, based on the clinical history and clinical manifestations. Moreover, it is helpful for a better understanding and teaching of these reactions.

[Cutaneous adverse drug reactions in childhood and adolescence]

Adverse drug reactions (ADR) occur in nearly 10% of hospitalized children and in about 1.5% of ambulatory pediatric patients. The skin is the most frequently affected target organ in drug hypersensitivity (DH) reactions, which account for 20% of all ADR. Due to its pathophysiological heterogeneity and the ensuing morphological diversity, DH often represents a clinical and therapeutic challenge. Urticarial and maculopapular eruptions are usually restricted to the skin and rarely require systemic treatment or hospital admission once the culprit drug has been withdrawn. However, extracutaneous affections should be ruled out promptly in individuals with polymorphous rashes accompanied by fever and lymphadenopathy as well as in patients with bullous skin lesions. Children affected by severe drug reactions usually require in-hospital surveillance and interdisciplinary supportive therapy.

Strategy for NSAID administration to aspirin-intolerant asthmatics in combination with PGE2 analogue: a theoretical approach

Aspirin-induced asthma (AIA) is a severe inflammatory disease, which affects aspirin-intolerant patients after ingestion of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs). In this article, a mathematical model describing arachidonic acid metabolism and its interaction with NSAIDs, is used to study the strategy for safe managing of NSAIDs to AIA patients. Three different AIA patient populations are taken into consideration. First, the values of aspirin and ibuprofen limiting doses that might induce symptoms of AIA are calculated and compared to experimentally observed threshold doses to enlighten which AIA patient population is susceptible to aspirin and ibuprofen. Second, the methodology of NSAID administration is studied on AIA populations susceptible to aspirin and ibuprofen by using 1,000 mg dose of aspirin and 200 or 400 mg dose of ibuprofen followed by PGE(2) analogue dosing. Our model results show that successive doses of PGE(2) analogue applied at appropriate time after aspirin or ibuprofen ingestion would enable administration of both NSAIDs to AIA patients. PGE(2) analogue doses and the corresponding times of their applications are calculated. The model is also used to estimate the duration of symptoms of AIA for different aspirin and ibuprofen doses.

Response to a selective COX-2 inhibitor in patients with urticaria/angioedema induced by nonsteroidal anti-inflammatory drugs

BACKGROUND

In subjects with hypersensitivity reactions with cross-intolerance to nonsteroidal anti-inflammatory drugs (NSAIDs), tolerance to selective COX-2 inhibitors has not been evaluated in large series of well-phenotyped cases.

METHODS

We evaluated 252 patients with urticaria and/or angioedema caused by hypersensitivity owing to cross-intolerance to NSAIDs. In addition to the clinical history, diagnosis was confirmed by provocation to an alternative NSAID. Two groups were considered: (A) patients with cross-intolerance to NSAIDs and intolerance to paracetamol and (B) patients with cross-intolerance to NSAIDs and good tolerance to paracetamol. Etoricoxib was administered to Group A patients and to a representative sample of Group B patients. In the event of a positive response, serum tryptase levels were determined and skin biopsy was performed in five patients in each group.

RESULTS

Ibuprofen was the most commonly implicated drug, followed by acetylsalicylic acid (ASA). Urticaria was the most common manifestation, followed by angioedema. Most of the patients developed symptoms within 1 h. Twenty-five percent in Group A (n = 47) and 6% in Group B (n = 50) were intolerant to etoricoxib. Skin biopsy showed mast cell activation with the release of tryptase to the extracellular space but without the increase in serum tryptase levels.

CONCLUSION

Selective COX-2 inhibitors may be unsafe in subjects with urticaria and/or angioedema caused by hypersensitivity reactions to NSAIDs with cross-intolerance if they are intolerant to paracetamol. A quarter of patients who were intolerant to this drug were also intolerant to etoricoxib. In subjects with hypersensitivity to NSAIDs and intolerance to paracetamol, selective COX-2 inhibitors should be administered as a controlled, incremental dose provocation test to assess tolerance.

Diagnosis and management of drug hypersensitivity reactions

The present article addresses the advances in the diagnosis and management of drug hypersensitivity reactions that were discussed in the 4th Drug Hypersensitivity Meeting held in Rome in April 2010. Such reactions can be classified as immediate or nonimmediate according to the time interval between the last drug administration and onset. Immediate reactions occur within 1 hour, and nonimmediate reactions occur after more than 1 hour. Clinical and immunologic studies suggest that type-I (IgE-mediated) and type-IV (T cell-mediated) pathogenic mechanisms are involved in most immediate and nonimmediate reactions, respectively. In diagnosis prick, patch, and intradermal tests are the most readily available tools. Determination of specific IgE levels is still the most common in vitro method for diagnosing immediate reactions. New diagnostic tools, such as the basophil activation test, the lymphocyte activation test, and enzyme-linked immunospot assays for analysis of the frequency of antigen-specific, cytokine-producing cells, have been developed for evaluating either immediate or nonimmediate reactions. The sensitivity of allergologic tests is not 100%; therefore in selected cases provocation tests are necessary. In the diagnosis of nonallergic hypersensitivity reactions to nonsteroidal anti-inflammatory drugs, the provocation test with the suspected drug still represents the "gold standard." However, there was no consensus regarding the use of this test in subjects with histories of hypersensitivity reactions to 1 (single reactors) or more (multiple reactors) nonsteroidal anti-inflammatory drugs. With regard to management, desensitization allows patients to be treated with irreplaceable chemotherapy agents, such as taxanes, platinum salts, and mAbs, to which they have presented hypersensitivity reactions. Desensitization also permits the use of aspirin in aspirin-sensitive patients undergoing revascularization and in subjects with aspirin-exacerbated respiratory disease.