Aspirin-triggered 15-HETE generation in peripheral blood leukocytes is a specific and sensitive Aspirin-Sensitive Patients Identification Test (ASPITest)

Meloxicam and/or Etoricoxib Could Be Administered Safely in Two Equal Doses during an Open Oral Challenge in Patients with Nonsteroidal Anti-Inflammatory Drug Hypersensitivity

BACKGROUND

Hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs) are common. These patients require an effective and safe analgesic alternative.

OBJECTIVE

The aim of the study was to demonstrate the safety of meloxicam and etoricoxib administered by open oral challenge in 2 equal steps in patients with NSAID hypersensitivity.

METHODS

A cross-sectional, descriptive study of patients with a diagnosis of NSAID hypersensitivity who underwent an oral drug provocation test (DPT) with meloxicam or etoricoxib between January 2011 and August 2017 was conducted. The analysis was performed from a database in BD Clinic.

RESULTS

Two hundred and twenty-eight oral provocations were performed with an alternative NSAID (203 with meloxicam and 25 with etoricoxib) in 217 patients with hypersensitivity to NSAIDs. The median age was 38 years. Ninety-eight percent of meloxicam and 100% of etoricoxib DPTs were performed in 2 steps (without previous placebo), and 52% and 64% of meloxicam and etoricoxib DPTs, respectively, were performed with 50% of the therapeutic dose in each step. Tolerance to meloxicam was demonstrated in 192 patients (94.5%) and in 100% of patients receiving etoricoxib.

CONCLUSIONS

Open oral provocation with meloxicam and etoricoxib carried out in 2 steps without placebo seems to be safe and implies less costs and less time expenditure. Also, it could be performed with 2 equal doses.

NSAID-Exacerbated Respiratory Disease (NERD): From Pathogenesis to Improved Care

Nonsteroidal antiinflammatory drug (NSAID)-exacerbated respiratory disease (NERD) is characterized by moderate-to-severe asthma and a higher prevalence of chronic rhinosinusitis/nasal polyps, but is a highly heterogeneous disorder with various clinical manifestations. Two major pathogenic mechanisms are: (1) overproduction of cysteinyl leukotrienes with dysregulation of arachidonic acid metabolism and (2) increased type 2 eosinophilic inflammation affected by genetic mechanisms. Aspirin challenge is the gold standard to diagnose NERD, whereas reliable in vitro biomarkers have yet not been identified. Therapeutic approaches have been done on the basis of disease severity with the avoidance of culprit and cross-reacting NSAIDs, and when indicated, aspirin desensitization is an effective treatment option. Biologic approaches targeting Type 2 cytokines are emerging as potential therapeutic options. Here, we summarize the up-to-date evidence of pathophysiologic mechanisms and diagnosis/management approaches to the patients with NERD with its phenotypic classification.

Artificial neural network identifies nonsteroidal anti-inflammatory drugs exacerbated respiratory disease (N-ERD) cohort

Background

To date, there has been no reliable in vitro test to either diagnose or differentiate nonsteroidal anti‐inflammatory drug (NSAID)–exacerbated respiratory disease (N‐ERD). The aim of the present study was to develop and validate an artificial neural network (ANN) for the prediction of N‐ERD in patients with asthma.

Methods

This study used a prospective database of patients with N‐ERD (n = 121) and aspirin‐tolerant (n = 82) who underwent aspirin challenge from May 2014 to May 2018. Eighteen parameters, including clinical characteristics, inflammatory phenotypes based on sputum cells, as well as eicosanoid levels in induced sputum supernatant (ISS) and urine were extracted for the ANN.

Results

The validation sensitivity of ANN was 94.12% (80.32%‐99.28%), specificity was 73.08% (52.21%‐88.43%), and accuracy was 85.00% (77.43%‐92.90%) for the prediction of N‐ERD. The area under the receiver operating curve was 0.83 (0.71‐0.90).

Conclusions

The designed ANN model seems to have powerful prediction capabilities to provide diagnosis of N‐ERD. Although it cannot replace the gold‐standard aspirin challenge test, the implementation of the ANN might provide an added value for identification of patients with N‐ERD. External validation in a large cohort is needed to confirm our results.

Conjugation of 4-aminosalicylate with thiazolinones afforded non-cytotoxic potent in vitro and in vivo anti-inflammatory hybrids

Eicosanoids like leukotrienes and prostaglandins that produced within the arachidonic acid cascade are involved in the pathogenesis of pain, acute and chronic inflammatory diseases. A promising approach for an effective anti-inflammatory therapy is the development of inhibitors targeting more than one enzyme of this cascade. Aiming to develop balanced COX/LOX inhibitors; 4-aminosalicylate based thiazolinones having different substituents at the 5th position of the 4-thiazolinone ring (2-22) were designed, synthesized, characterized and evaluated in vitro and in vivo for their anti-inflammatory activity. Most of the investigated compounds showed high COX-2 inhibitory potencies (IC₅₀ 39-200 nM) with selectivity indexes (30-84). Two compounds, 19 and 21, (IC₅₀ = 41 and 44 nM), are equipotent to celecoxib (IC₅₀ = 49 nM), while compound 22 (IC₅₀ = 39 nM) was the most potent. For 15-LOX, compounds 5, 11, 19, 21 and 22 revealed higher potency (IC₅₀ 1.5-2.2 µM) than zileuton (IC₅₀ 15 µM). Thus, compounds 5, 11, 19, 21 and 22 are potent dual inhibitors of COX-2 and 15-LOX. In vivo anti-inflammatory testing of these compounds revealed that, compounds 5 and 21 had an anti-inflammatory activity similar to indomethacin and celecoxib (% inhibition of oedema = 60 ± 9) and higher than diclofenac potassium (% inhibition = 52 ± 29), while compound 22 (% inhibition = 63 ± 5) was more active than the reference drugs. The results showed that the activity is controlled by the bulkiness and lipophilicity of the substituent at the 5th position. The cytotoxicity results revealed that all compounds are not cytotoxic, additionally, in an experimental model of ulcerogenic effect, the most active compounds 21 and 22 showed better safety profile than indomethacin. Further, at the active sites of the COX-1, COX-2 and 15-LOX co-crystal, 19, 21, and 22 showed high binding forces in free binding energy study, which is consistent with in vitro and in vivo results. In conclusion, these compounds are good candidates for further biological investigation as potential anti-inflammatory drugs with dual balanced inhibition of COX and 15-LOX and good safety profile.

Diagnosis and management of NSAID-Exacerbated Respiratory Disease (N-ERD)-a EAACI position paper

NSAID-exacerbated respiratory disease (N-ERD) is a chronic eosinophilic, inflammatory disorder of the respiratory tract occurring in patients with asthma and/or chronic rhinosinusitis with nasal polyps (CRSwNP), symptoms of which are exacerbated by NSAIDs, including aspirin. Despite some progress in understanding of the pathophysiology of the syndrome, which affects 1/10 of patients with asthma and rhinosinusitis, it remains a diagnostic and therapeutic challenge. In order to provide evidence-based recommendations for the diagnosis and management of N-ERD, a panel of international experts was called by the EAACI Asthma Section. The document summarizes current knowledge on the pathophysiology and clinical presentation of N-ERD pointing at significant heterogeneity of this syndrome. Critically evaluating the usefulness of diagnostic tools available, the paper offers practical algorithm for the diagnosis of N-ERD. Recommendations for the most effective management of a patient with N-ERD stressing the potential high morbidity and severity of the underlying asthma and rhinosinusitis are discussed and proposed. Newly described sub-phenotypes and emerging sub-endotypes of N-ERD are potentially relevant for new and more specific (eg, biological) treatment modalities. Finally, the document defines major gaps in our knowledge on N-ERD and unmet needs, which should be addressed in the future.

Synthesis, biological evaluation and docking study of 1,3,4-thiadiazole-thiazolidinone hybrids as anti-inflammatory agents with dual inhibition of COX-2 and 15-LOX

Selective inhibition of both cyclooxygenase-2 (COX-2) and 15-lipooxygenase (15-LOX) may provide good strategy for alleviation of inflammatory disorders while minimizing side effects associated with current anti-inflammatory drugs. The present study describes the synthesis, full characterization and biological evaluation of a series of thiadiazole-thiazolidinone hybrids bearing 5-alk/arylidene as dual inhibitors of these enzymes. Our design was based on merging pharmacophores that exhibit portent anti-inflammatory activities in one molecular frame. 5-(4-hydroxyphenyl)-1,3,4-thiadiazol-2-amine (3) was efficiently synthesized, chloroacetylated and cyclized to give the key 4-thiazolidinone (5). Knovenagel condensation of 5 with different aldehydes afforded the final compounds 6a-m, 7, 8 and 9. These compounds were subjected to in vitro COX-1/COX-2, 15-LOX inhibition assays. Compounds (6a, 6f, 6i, 6l, 6m and 9) with promising potency (IC₅₀ = 70-100 nM) and selectivity index (SI = 220-55) were further tested for in vivo anti-inflammatory activity and effect on gastric mucosa. The most promising compound (6l) inhibits COX-2 enzyme at a nanomolar concentration (IC₅₀ = 70 nM, SI = 220) with simultaneous inhibition of 15-LOX (IC₅₀ = 11 µM). These results are comparable to the potency and selectivity of the standard drugs of both enzymes; celecoxib (COX-2 IC₅₀ = 49 nM, SI = 308) and zileuton (15-LOX IC₅₀ = 15 µM) in one construct. Interestingly three compounds (6a, 6l and 9) exhibited equivalent to or even higher than that of celecoxib in vivo anti-inflammatory activity at 3 h interval with good GIT safety profile. Molecular docking study conferred binding sites of these compounds on COX-2 and 15-LOX. Such type of compounds would represent valuable leads for further investigation and derivatization.

Aspirin exacerbated respiratory disease: Current topics and trends

Aspirin-exacerbated respiratory disease is a chronic and treatment-resistant disease, characterized by the presence of eosinophilic rhinosinusitis, nasal polyposis, bronchial asthma, and nonsteroidal anti-inflammatory drugs hypersensitivity. Alterations in arachidonic acid metabolism may induce an imbalance between pro-inflammatory and anti-inflammatory substances, expressed as an overproduction of cysteinyl leukotrienes and an underproduction of prostaglandin E2. Although eosinophils play a key role, recent studies have shown the importance of other cells and molecules in the development of the disease like mast cells, basophils, lymphocytes, platelets, neutrophils, macrophages, epithelial respiratory cells, IL-33 and thymic stromal lymphopoietin, making each of them promissory diagnostic and treatment targets. In this review, we summarize the most important clinical aspects of the disease, including the current topics about diagnosis and treatment, like provocation challenges and aspirin desensitization. We also discuss recent findings in the pathogenesis of the disease, as well as future trends in diagnosis and treatment, including monoclonal antibodies and a low salicylate diet as a treatment option.

Plasma 15-Hydroxyeicosatetraenoic Acid Predicts Treatment Outcomes in Aspirin-Exacerbated Respiratory Disease

BACKGROUND

Aspirin desensitization followed by daily aspirin provides therapeutic benefits to patients with aspirin-exacerbated respiratory disease (AERD). It is not well understood how eicosanoid levels change during aspirin treatment.

OBJECTIVE

To investigate associations between clinical outcomes of aspirin treatment and plasma eicosanoid levels in patients with AERD.

METHODS

Thirty-nine patients with AERD were offered aspirin treatment (650 mg twice daily) for 4 weeks. Respiratory parameters and plasma levels of multiple eicosanoids were recorded at baseline and after 4 weeks of aspirin therapy using the Asthma Control Test and Rhinoconjunctivitis Quality of Life Questionnaire. Respiratory function was evaluated using the FEV₁ and nasal inspiratory peak flow.

RESULTS

After aspirin treatment, respiratory symptoms improved in 16 patients, worsened in 12 patients, and did not change in 4 patients. Seven patients were unable to complete the desensitization protocol. Patients with symptom improvement had higher baseline plasma 15-hydroxyeicosatetraenoic acid (15-HETE) levels than did patients with symptom worsening: 7006 pg/mL (interquartile range, 6056-8688 pg/mL) versus 4800 pg/mL (interquartile range, 4238-5575 pg/mL), P = .0005. Baseline 15-HETE plasma levels positively correlated with the change in Asthma Control Test score (r = 0.61; P = .001) and in FEV₁ after 4 weeks of aspirin treatment (r = 0.49; P = .01). It inversely correlated with Rhinoconjunctivitis Quality of Life Questionnaire score (r = -0.58; P = .002). Black and Latino patients were more likely to have symptom worsening on aspirin or fail to complete the initial desensitization than white, non-Latino patients (P = .02).

CONCLUSIONS

In patients with AERD, low baseline 15-HETE plasma levels and black or Latino ethnicity are associated with worsening of respiratory symptoms during aspirin treatment.

Diagnostic Evaluation in Aspirin-Exacerbated Respiratory Disease

Aspirin-exacerbated respiratory disease (AERD) is a distinct clinical condition characterized by chronic sinusitis with nasal polyps, asthma, and hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs). Distinguishing AERD from other forms of chronic sinusitis, asthma, and NSAID reactivity has important clinical implications for management. The clinical history is helpful, but not adequate for confirming the diagnosis of AERD, in most cases. Diagnostic provocation challenge remains the only way to confirm or exclude the diagnosis of AERD. This article discusses the utility of the clinical history and the current evidence regarding measures that optimize the safety of performing diagnostic NSAID provocation challenges.

In vitro tests for drug hypersensitivity reactions: an ENDA/EAACI Drug Allergy Interest Group position paper

Drug hypersensitivity reactions (DHRs) are a matter of great concern, both for outpatient and in hospital care. The evaluation of these patients is complex, because in vivo tests have a suboptimal sensitivity and can be time-consuming, expensive and potentially risky, especially drug provocation tests. There are several currently available in vitro methods that can be classified into two main groups: those that help to characterize the active phase of the reaction and those that help to identify the culprit drug. The utility of these in vitro methods depends on the mechanisms involved, meaning that they cannot be used for the evaluation of all types of DHRs. Moreover, their effectiveness has not been defined by a consensus agreement between experts in the field. Thus, the European Network on Drug Allergy and Drug Allergy Interest Group of the European Academy of Allergy and Clinical Immunology has organized a task force to provide data and recommendations regarding the available in vitro methods for DHR diagnosis. We have found that although there are many in vitro tests, few of them can be given a recommendation of grade B or above mainly because there is a lack of well-controlled studies, most information comes from small studies with few subjects and results are not always confirmed in later studies. Therefore, it is necessary to validate the currently available in vitro tests in a large series of well-characterized patients with DHR and to develop new tests for diagnosis.

Use of nonsteroidal anti-inflammatory drugs in patients with aspirin hypersensitivity : safety of cyclo-oxygenase-2 inhibitors

This article provides information on the pathogenesis of aspirin hypersensitivity, cross-sensitivity, and cross-tolerance of different NSAIDs in patients with respiratory types of reactions. Hypersensitivity to aspirin may affect 5-20% of patients with chronic asthma and an unknown fraction of patients with chronic urticaria-angioedema. These patients develop cross-reactions to other, chemically non-related, NSAIDs with strong inhibitory activity towards cyclo-oxygenase (COX)-1 (e.g. indomethacin, naproxen, ketoprofen). Avoidance of aspirin and all cross-reacting NSAIDs as well as education of patients are crucial. As an alternative antipyretic or analgesic drug, aspirin-sensitive asthmatic patients may take acetaminophen (paracetamol) in low or moderate doses (<1000mg). Preferential COX-2 inhibitors (nimesulide, meloxicam) are tolerated by the majority but not all hypersensitive patients. Selective COX-2 inhibitors (celecoxib and rofecoxib [withdrawn from the market]) are well tolerated by almost all aspirin-sensitive asthmatic patients. In patients with coronary artery disease requiring treatment with aspirin, desensitization to aspirin may be an alternative approach. Thus, for the majority of patients with asthma and hypersensitivity to aspirin or other NSAIDs, an alternative anti-inflammatory drug can be found. However, in each individual case physicians must consider the choice of an alternative NSAID carefully.

The whole-genome expression analysis of peripheral blood mononuclear cells from aspirin sensitive asthmatics versus aspirin tolerant patients and healthy donors after in vitro aspirin challenge

Background

Up to 30 % of adults with severe asthma are hypersensitive to aspirin and no unambiguous theory exists which provides a satisfactory explanation for the occurrence of aspirin-induced asthma (AIA) in some asthmatic patients. Therefore, the aim of this study was to compare the AIA expression profile against aspirin tolerant asthma (ATA) and healthy volunteers (HV) profile in peripheral blood mononuclear cells (PBMCs) after in vitro aspirin challenge in Caucasian population.

Methods

PBMCs were separated from blood of three groups of subjects - 11 AIA, 7 ATA and 15 HV and then stimulated by either 2 μM lysine aspirin or 20 μM lysine as a control. Subsequently, RNA was isolated, transcribed into cDNA and subjected to microarray and qPCR studies. Simultaneously, protein was extracted from PBMCs and used in further immunoblotting analysis.

Results

The validation of results at mRNA level has shown only three genes, whose expression was significantly altered between comprising groups. mRNA expression of CNPY3 in PBMCs in AIA was significantly lower (-0.41 ± 2.67) than in HV (1.04 ± 2.69), (p = 0.02); mRNA expression of FOSL1 in PBMCs in AIA was also significantly decreased (-0.66 ± 2.97) as opposed to HV (0.31 ± 4.83), (p = 0.02). While mRNA expression of ERAS in PBMCs was increased (1.15 ± 0.23) in AIA in comparison to HV (-1.32 ± 0.41), (p = 0.03). At protein level the changed expression of one protein was confirmed. Protein expression of FOSL1 in PBMCs in AIA was both significantly lower (-0.86 ± 0.08) than in ATA (0.39 ± 0.42), (p = 0.046) and in HV (0.9 ± 0.27), (p = 0.007).

Conclusions

This pilot study implies a positive association between CNPY3, ERAS, FOSL1 and aspirin-intolerant asthma, suggesting that these findings would be useful for further investigations of NSAIDs mechanism.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0305-4) contains supplementary material, which is available to authorized users.

Hypersensitivity to Aspirin and other NSAIDs: Diagnostic Approach in Patients with Chronic Rhinosinusitis

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) associated with chronic rhinosinusitis (CRS) and/or asthma comprises a distinct clinical syndrome referred to as NSAIDs exacerbated respiratory disease (NERD). Patients with NERD tend to have more severe course of both upper (CRS and nasal polyps) and lower airway (asthma) diseases and are usually recalcitrant to conventional treatment modalities. Diagnosing and phenotyping of patients with NERD are critical for prevention of drug-induced adverse reactions and open novel options for management of underlying chronic airway inflammatory diseases. Diagnosis of NERD is based on detailed clinical history confirmed by challenge with aspirin, but new diagnostic approaches are currently being developed. This review article focuses on the diagnostic approach to a patient with CRS and hypersensitivity to NSAIDs, emphasizing the importance of diagnosis for proper patient's management.

Dipeptidyl-peptidase 10 as a genetic biomarker for the aspirin-exacerbated respiratory disease phenotype

BACKGROUND

Aspirin-exacerbated respiratory disease (AERD) is an endotype of severe and eosinophilic adult asthma characterized by chronic rhinosinusitis with nasal polyps and hypersensitivity to aspirin and/or nonsteroidal anti-inflammatory drugs. A genetic contribution of dipeptidyl-peptidase 10 (DPP10) to asthma susceptibility and lung function decline has been reported. However, little is known about the role of DPP10 in the pathogenesis of AERD.

OBJECTIVE

To identify genetic variants of DPP10 that confer susceptibility to AERD or severe asthma.

METHODS

A case-control association study of DPP10 gene polymorphisms was performed in 3 groups of patients: 274 with AERD, 272 with aspirin-tolerant asthma, and 99 normal healthy controls. The rs17048175 single-nucleotide polymorphism was targeted based on a preliminary genomewide association study using an Affymetrix genomewide human single-nucleotide polymorphism array in a Korean population. DPP10, 15-hydroxyeicosatetraenoic acid, and YKL-40/chitinase-3-like protein were measured by enzyme-linked immunosorbent assay in sera taken from the study subjects.

RESULTS

There was a significant association between rs17048175 and the AERD phenotype, but not with aspirin-tolerant asthma. The DPP10 level was significantly higher in sera from patients with AERD compared with patients with aspirin-tolerant asthma and control subjects (P = .021 and P < .001, respectively). In addition, there was a significant difference of serum DPP10 level according to the single-nucleotide polymorphism (P = .001). Serum DPP10 level showed a strong correlation with 15-hydroxyeicosatetraenoic acid (r = 0.226, P = .017) and YKL-40 (r = 0.364, P = .004).

CONCLUSION

This study suggests a genetic contribution of rs17048175 to DPP10 in eosinophilic inflammation induction in the airways and to AERD susceptibility.

Recent advance in investigation of gene polymorphisms in Japanese patients with aspirin-exacerbated respiratory disease

Aspirin-exacerbated respiratory disease (AERD) is a complex clinical syndrome characterised by severe asthmatic attack upon treatment with aspirin and/or non-steroidal anti-inflammatory drugs (NSAIDs). Genetic predisposition has been considered as a crucial determinant and candidate genes have concentrated especially on cysteinyl leukotrienes (LTs)-related genes as the inhibitory action of aspirin and NSAIDs on cyclooxygenase activity may cause overproduction of cysteinyl LTs. However, conflicting results have been reported, in parallel with replication studies in different ethnic groups. Thus, future areas of investigations need to focus on comprehensive approaches towards the discovery of other genetic biomarkers. Unfortunately, few papers have been reported about gene polymorphisms in Japanese patients with AERD. Here, we described on our recent genetic investigations on B2ADR, IL-13, IL-17A, CYP2C19, TBXA2R, CRTH2 and HSP70. This review indicates potential genetic biomarkers contributing to the early diagnosis of AERD, which may include CYP2C19 and HSP70 gene polymorphisms, and future validation studies in independent population are required to provide reassurance about our findings.

The SNP rs3128965 of HLA-DPB1 as a genetic marker of the AERD phenotype

BACKGROUND

Two common clinical syndromes of acetylsalicylic acid (aspirin) hypersensitivity, aspirin-exacerbated respiratory disease (AERD) and aspirin-exacerbated cutaneous disease (AECD), were subjected to a genome-wide association study to identify strong genetic markers for aspirin hypersensitivity in a Korean population.

METHODS

A comparison of SNP genotype frequencies on an Affymetrix Genome-Wide Human SNP array of 179 AERD patients and 1989 healthy normal control subjects (NC) revealed SNPs on chromosome 6 that were associated with AERD, but not AECD. To validate the association, we enrolled a second cohort comprising AERD (n = 264), NC (n = 238) and disease-control (aspirin tolerant asthma; ATA, n = 387) groups.

RESULTS

The minor genotype frequency (AG or AA) of a particular SNP, rs3128965, in the HLA-DPB1 region was higher in the AERD group compared to the ATA or NC group (P = 0.001, P = 0.002, in a co-dominant analysis model, respectively). Comparison of rs3128965 alleles with the clinical features of asthmatics revealed that patients harboring the A allele had increased bronchial hyperresponsiveness to inhaled aspirin and methacholine, and higher 15-HETE levels, than those without the A allele (P = 0.039, 0.037, and 0.004, respectively).

CONCLUSIONS

This implies the potential of rs3128965 as a genetic marker for diagnosis and prediction of the AERD phenotype.

Classification and practical approach to the diagnosis and management of hypersensitivity to nonsteroidal anti-inflammatory drugs

Hypersensitivity reactions to aspirin (acetylsalicylic acid) and other nonsteroidal anti-inflammatory drugs (NSAIDs) constitute only a subset of all adverse reactions to these drugs, but due to their severity pose a significant burden to patients and are a challenge to the allergist. In susceptible individuals, NSAIDs induce a wide spectrum of hypersensitivity reactions with various timing, organ manifestations, and severity, involving either immunological (allergic) or nonimmunological mechanisms. Proper classification of reactions based on clinical manifestations and suspected mechanism is a prerequisite for the implementation of rational diagnostic procedures and adequate patient management. This document, prepared by a panel of experts from the European Academy of Allergy and Clinical Immunology Task Force on NSAIDs Hypersensitivity, aims at reviewing the current knowledge in the field and proposes uniform definitions and clinically useful classification of hypersensitivity reactions to NSAIDs. The document proposes also practical algorithms for the diagnosis of specific types of NSAIDs hypersensitivity (which include drug provocations, skin testing and in vitro testing) and provides, when data are available, evidence-based recommendations for the management of hypersensitive patients, including drug avoidance and drug desensitization.

Upregulation of CD11b on eosinophils in aspirin induced asthma

BACKGROUND

Although a challenge test using non-steroidal anti-inflammatory drugs (NSAIDs) is crucial for diagnosis of aspirin-induced asthma (AIA), it also has drawbacks in terms of possible side effects. Therefore, alternative in-vitro diagnostic methods for AIA are awaited.

METHODS

Nineteen stable non-AIA patients (9 males and 10 females; mean age, 49.4 ± 4.8 years), and 20 AIA patients (9 males and 11 females; mean age, 51.1 ± 4.8 years) were enrolled in this study. CD11b and CD16 expressions on the peripheral-blood granulocytes after administration of aspirin and different concentrations of PGE2 in vitro were examined using flowcytometry.

RESULTS

Aspirin induced a significant increase in CD11b expression on eosinophils (CD16 negative granulocytes) in 19 AIA patients and one non-AIA patient. Increase in CD11b expression on eosinophils by aspirin administration was suppressed by PGE2 in a dose-dependent manner.

CONCLUSIONS

The measurement of CD11b expression on peripheral-blood eosinophils showed very high sensitivity and specificity of (-95%) in diagnosing AIA. Although this method requires laboratory facilities for flowcytometry, it may be very useful in diagnosis of AIA without side effects. In addition, PGE2 may be involved in regulation of CD11b expression on eosinophils by aspirin administration.

The influence of aspirin on release of eoxin C4, leukotriene C4 and 15-HETE, in eosinophilic granulocytes isolated from patients with asthma

BACKGROUND

The effect of aspirin on the release of key arachidonic acid metabolites in activated eosinophils from subjects with aspirin-intolerant asthma (AIA) has not been investigated previously, despite the characteristic eosinophilia in AIA.

METHODS

Peripheral blood eosinophils were isolated from four groups of subjects: healthy volunteers (HV; n = 8), mild asthma (MA; n = 8), severe asthma (SA; n = 9) and AIA (n = 7). In the absence or presence of lysine-aspirin, eosinophils were stimulated with arachidonic acid or calcium ionophore to trigger the 15-lipoxygenase-1 (15-LO) and 5-lipoxygenase (5-LO) pathways, respectively. 15(S)-hydroxy-eicosatetraenoic acid (15-HETE) and eoxin C4 (EXC4) were measured as 15-LO products and leukotriene (LT)C4 as a product of the 5-LO pathway.

RESULTS

Activated eosinophils from patients with SA and AIA produced approximately five times more 15-HETE than eosinophils from HV or MA patients. In the presence of lysine-aspirin, eosinophils from AIA, MA and SA patients generated higher levels of 15-HETE than in the absence of lysine-aspirin. Furthermore, in the presence of lysine-aspirin, formation of EXC4 was also significantly increased in eosinophils from AIA patients, and LTC4 synthesis was increased both in AIA and SA patients.

CONCLUSIONS

Taken together, this study shows an increased release of the recently discovered lipid mediator EXC4, as well as the main indicator of 15-LO activity, 15-HETE, in activated eosinophils from severe and aspirin-intolerant asthmatics, and also elevated EXC4 and LTC4 formation in eosinophils from AIA patients after cellular activation in the presence of lysine-aspirin. The findings support a pathophysiological role of the 15-LO pathway in SA and AIA.

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.

Genetic variants of the arachidonic acid pathway in non-steroidal anti-inflammatory drug-induced acute urticaria

BACKGROUND

To date, genetic studies of hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) have been carried out mainly in aspirin-induced asthma and to a lesser extent in chronic urticaria, with no studies in patients with acute urticaria (AU), the most common entity induced by these drugs.

OBJECTIVE

In this work, we analysed the association of common variants of 15 relevant genes encoding both enzymes and receptors from the arachidonic acid (AA) pathway with NSAID-induced AU.

METHODS

Patients were recruited in several Allergy Services that are integrated into the Spanish network RIRAAF, and diagnosed of AU induced by cross-intolerance (CRI) to NSAIDs. Genotyping was carried out by TaqMan allelic discrimination assays.

RESULTS

A total of 486 patients with AU induced by CRI to NSAIDs and 536 unrelated controls were included in this large Spanish case-control study. Seven variants from 31 tested in six genes were associated in a discovery study population from Malaga (0.0003 ≤ p-value ≤ 0.041). A follow-up analysis in an independent sample from Madrid replicated three of the SNPs from the ALOX15 (rs7220870), PTGDR (rs8004654) and CYSLTR1 (rs320095) genes (1.055x10(-6) ≤meta-analysis p-value ≤ 0.003).

CONCLUSIONS AND CLINICAL RELEVANCE

Genetic variants of the AA pathway may play an important role in NSAID-induced AU. These data may help understand the mechanism underlying this disease.

Rhinosinusitis and nasal polyps in aspirin-exacerbated respiratory disease

The presence of aspirin-exacerbated respiratory disease (AERD) in a patient with chronic rhinosinusitis with nasal polyps and asthma is associated with severe eosinophilic upper and lower airway disease. This article deals with the inflammatory disease of the respiratory tract as it relates to the sinuses. Involvement of the sinuses in AERD is almost universal, depending on the stage of onset of the disease and evaluation by computed tomography. This article explores the clinical aspects, physiopathology, and treatment of rhinosinusitis as it relates to AERD.

Genetics of hypersensitivity to aspirin and nonsteroidal anti-inflammatory drugs

Various hypersensitivity reactions have been reported with aspirin and nonsteroidal anti-inflammatory drugs. Hypersensitivity can occur regardless of a chemical drug structure or its therapeutic potency. Allergic conditions include aspirin-exacerbated respiratory disease (AERD or aspirin-induced asthma), aspirin-induced urticaria/angioedema (AIU), and anaphylaxis. Several genetic studies on aspirin hypersensitivity have been performed to discover the genetic predisposition to aspirin hypersensitivity and to gain insight into the phenotypic diversity. This article updates data on the genetic mechanisms that govern AERD and AIU and summarizes recent findings on the molecular genetic mechanism of aspirin hypersensitivity.

Pathogenic Mechanisms and In Vitro Diagnosis of AERD

Aspirin-exacerbated respiratory disease (AERD) refers to chronic rhinosinusitis, nasal polyposis, bronchoconstriction, and/or eosinophilic inflammation in asthmatics following the exposure to nonsteroidal anti-inflammatory drugs (NSAIDs). A key pathogenic mechanism associated with AERD is the imbalance of eicosanoid metabolism focusing on prostanoid and leukotriene pathways in airway mucosa as well as blood cells. Genetic and functional metabolic studies on vital and non-vital cells pointed to the variability and the crucial role of lipid mediators in disease susceptibility and their response to medication. Eicosanoids, exemplified by prostaglandin E(2) (PGE(2)) and peptidoleukotrienes (pLT), are potential metabolic biomarkers contributing to the AERD phenotype. Also other mediators are implicated in the progress of AERD. Considering the various pathogenic mechanisms of AERD, a multitude of metabolic and genetic markers is suggested to be implicated and were introduced as potential biomarkers for in vitro diagnosis during the past decades. Deduced from an eicosanoid-related pathogenic mechanism, functional tests balancing PGE(2) and pLT as well as other eicosanoids from preferentially vital leukocytes demonstrated their applicability for in vitro diagnosis of AERD.

Flow Cytometry-Assisted Basophil Activation Test as a Safe Diagnostic Tool for Aspirin/NSAID Hypersenstivity

Purpose

Aspirin and non-steroidal anti-inflammatory drugs (ASA/NSAIDs) are common causes of drug hypersensitivity. An oral provocation test is the only definitive diagnostic test. This study assessed the reliability of a flow cytometry-assisted basophil activation test (FAST) as a safe diagnostic method for ASA/NSAID-induced hypersensitivity, as its high sensitivity and specificity have been demonstrated for many other drugs.

Methods

Eighteen patients and 11 controls were enrolled. Using a Flow-CAST kit® (Bühlmann Laboratories AG, Schönenbuch, Switzerland), 29 analyses with aspirin, ibuprofen, and diclofenac were performed by flow cytometry to detect double-positive staining of anti-IgE and anti-CD63. The stimulation index was defined as the activated basophil percentage after drug stimulation/basally active basophil percentage. A stimulation index≥2 and an absolute activated basophil percentage≥5 were considered positive.

Results

Patients with hypersensitivity to ASA/NSAIDs were predominantly female, and the prevalence of atopy was higher in patients than in controls. A sensitivity of 61%, specificity of 91%, positive predictive value of 92%, and negative predictive value of 59% were achieved.

Conclusions

FAST is a useful additional method for diagnosis of hypersensitivity reactions to ASA/NSAIDs. Further development is required to increase the sensitivity of the test.

Exhaled Eicosanoids following Bronchial Aspirin Challenge in Asthma Patients with and without Aspirin Hypersensitivity: The Pilot Study

Background. Special regulatory role of eicosanoids has been postulated in aspirin-induced asthma. Objective. To investigate effects of aspirin on exhaled breath condensate (EBC) levels of eicosanoids in patients with asthma. Methods. We determined EBC eicosanoid concentrations using gas chromatography/mass spectrometry (GC-MS) and high-performance liquid chromatography/mass spectrometry (HPLC-MS²) or both. Determinations were performed at baseline and following bronchial aspirin challenge, in two well-defined phenotypes of asthma: aspirin-sensitive and aspirin-tolerant patients. Results. Aspirin precipitated bronchial reactions in all aspirin-sensitive, but in none of aspirin-tolerant patients (ATAs). At baseline, eicosanoids profile did not differ between both asthma groups except for lipoxygenation products: 5- and 15-hydroxyeicosatetraenoic acid (5-, 15-HETE) which were higher in aspirin-induced asthma (AIA) than inaspirin-tolerant subjects. Following aspirin challenge the total levels of cysteinyl-leukotrienes (cys-LTs) remained unchanged in both groups. The dose of aspirin had an effect on magnitude of the response of the exhaled cys-LTs and prostanoids levels only in AIA subjects. Conclusion. The high baseline eicosanoid profiling of lipoxygenation products 5- and 15-HETE in EBC makes it possible to detect alterations in aspirin-sensitive asthma. Cysteinyl-leukotrienes, and eoxins levels in EBC after bronchial aspirin administration in stable asthma patients cannot be used as a reliable diagnostic index for aspirin hypersensitivity.

Comparison of CD63 Upregulation Induced by NSAIDs on Basophils and Monocytes in Patients with NSAID Hypersensitivity

Background. An in vitro basophil activation test, based on the detection of CD63 upregulation induced by NSAIDs, has been described. Its clinical significance remains controversial. Objectives. In patients with a history of nonallergic NSAID hypersensitivity, stratified according to the severity of the symptoms, to assess with NSAIDs the predictive value of basophil (BAT) and monocyte (MAT) activation tests. Patients/Methods. Sixty patients who had NSAIDs-induced or exacerbated urticaria/angiooedema and 20 controls was included. After incubation with NSAIDs or acetaminophen, leukocytes were analysed for CD63 upregulation. Results. With aspirin, the sensitivity (37%) and specificity (90%) of BAT agree with already published results. In contrast, when patients had had cutaneous and visceral reactions, the frequency of positive BAT 14/22 (64%, P < 0.001) or MAT 10/22 (46%, P < 0.01) were increased. Conclusions. Positive tests were more frequent among patients having a severe hypersensitivity contrasting with the other patients who had results similar to controls.

Expression of arachidonate metabolism enzymes and receptors in nasal polyps of aspirin-hypersensitive asthmatics

BACKGROUND

The pathogenesis of rhinosinusitis in aspirin-exacerbated airway disease is closely linked to the disequilibrium in arachidonic acid metabolism. Although considerable amounts of data concerning impaired eicosanoid production are available, the precise mechanism and pathogenesis of the disease are still unknown. The aim of the present study was to assess the expression of enzymes belonging to the arachidonic acid cascade and receptors for arachidonate derivative metabolites in nasal polyps from aspirin- hypersensitive (AH) and aspirin-tolerant (AT) patients with rhinosinusitis.

METHODS

Cells expressing cysteinyl leukotriene (CysLT) receptors (CysLT(1) and CysLT(2)), arachidonate 5-lipoxygenase, leukotriene B(4) receptor type 1, E-prostanoid receptors (EP(2) and EP(4)), cyclooxygenase (COX)-1 and COX-2 were detected by immunocytochemistry in nasal polyps obtained from 10 AH patients and 18 AT patients.

RESULTS

There was a significantly higher density of cells expressing CysLT(1) and CysLT(2) receptors in nasal polyps from AH patients than from AT patients (p < 0.001). In contrast, the density of cells expressing EP(2) receptor and COX-2 was significantly lower in AH patients than in AT patients (p < 0.02). The number of COX-2-positive epithelial cells was significantly reduced in AH polyps (p < 0.04).

CONCLUSIONS

The elevated number of nasal polyp cells expressing CysLT receptors and lack of cells expressing EP(2) receptor and COX-2 may be related to a more severe course of hyperplastic rhinosinusitis in aspirin hypersensitivity.

The nose as a target organ in the diagnosis of severe aspirin-exacerbated respiratory disease

BACKGROUND

The nasal provocation test (NPT) with lysine aspirin is a useful tool in the diagnosis of aspirin-exacerbated respiratory disease (AERD), previously reffered to as Samter's disease. The aim of the present study focuses on methodological interventions to show the usefulness of the NPT with lysine aspirin in differentiating AERD patients from aspirin-tolerant asthma (ATA) patients to improve the diagnostic efficacy and minimize the risk for adverse reactions compared with the gold standard.

METHODS

Thirty AERD patients comprised the active study group while the control group consisted of 25 ATA patients. A combination of objective nasal aerodynamic response (i.e., nasal inspiratory flow and nasal inspiratory resistance) was evaluated by active anterior rhinomanometry and the subjective clinical nasal and extranasal symptoms (including forced expiratory volume) were monitored throughout the challenge.

RESULTS

Fifty-five NPTs were successfully completed: sensitivity, 87%; specificity, 100%; positive predictive value, 100%; negative predictive value, 86%; global efficacy, 92.72%. No severe adverse reactions were recorded.

CONCLUSION

The present NPT with lysine aspirin proved to be a safe, efficient, and a timesaving method in the diagnosis of patients with AERD, even in those with severe rhinitis-rhinosinusitis and/or recurrent nasal polyposis.

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) - classification, diagnosis and management: review of the EAACI/ENDA(#) and GA2LEN/HANNA*

Nonsteroidal anti-inflammatory drugs (NSAIDs) are responsible for 21-25% of reported adverse drug events which include immunological and nonimmunological hypersensitivity reactions. This study presents up-to-date information on pathomechanisms, clinical spectrum, diagnostic tools and management of hypersensitivity reactions to NSAIDs. Clinically, NSAID hypersensitivity is particularly manifested by bronchial asthma, rhinosinusitis, anaphylaxis or urticaria and variety of late cutaneous and organ-specific reactions. Diagnosis of hypersensitivity to a NSAID includes understanding of the underlying mechanism and is necessary for prevention and management. A stepwise approach to the diagnosis of hypersensitivity to NSAIDs is proposed, including clinical history, in vitro testing and/or provocation test with a culprit or alternative drug depending on the type of the reaction. The diagnostic process should result in providing the patient with written information both on forbidden and on alternative drugs.

Hypersensitivity Reactions to Nonsteroidal Anti-Inflammatory Drugs: An Update

After beta lactam antibiotics, hypersensitivity reactions to nonsteroidal anti-inflammatory drugs are the second cause of hypersensitivity to drugs. Acute manifestations affect the respiratory tract (aspirin exacerbated respiratory disease), the skin (urticaria and angioedema), or are generalized (anaphylaxis). Correct diagnosis and treatment in order to prevent unnecessary morbidity and the potential risk of death from these severe reactions, and to provide proper medical advice on future drug use frequently requires the participation of allergology specialists familiar with these clinical conditions.

Update on recent advances in the management of aspirin exacerbated respiratory disease

Aspirin intolerant asthma (AIA) is frequently characterized as an aspirin (ASA)-exacerbated respiratory disease (AERD). It is a clinical syndrome associated with chronic severe inflammation in the upper and lower airways resulting in chronic rhinitis, sinusitis, recurrent polyposis, and asthma. AERD generally develops secondary to abnormalities in inflammatory mediators and arachidonic acid biosynthesis expression. Upper and lower airway eosinophil infiltration is a key feature of AERD; however, the exact mechanisms of such chronic eosinophilic inflammation are not fully understood. Cysteinyl leukotriene over-production may be a key factor in the induction of eosinophilic activation. Genetic studies have suggested a role for variability of genes in disease susceptibility and response to medication. Potential genetic biomarkers contributing to the AERD phenotype include HLA-DPB1*301, LTC4S, ALOX5, CYSLT, PGE2, TBXA2R, TBX21, MS4A2, IL10 -1082A > G, ACE -262A > T, and CRTH2 -466T > C; the four-locus SNP set was composed of B2ADR 46A > G, CCR3 -520T > G, CysLTR1 -634C > T, and FCER1B -109T > C. Management of AERD is an important issue. Aspirin ingestion may result in significant morbidity and mortality, and patients must be advised regarding aspirin risk. Leukotriene receptor antagonists (LTRA) that inhibit leukotriene pathways have an established role in long-term AERD management and rhinosinusitis. Aspirin desensitization may be required for the relief of upper and lower airway symptoms in AERD patients. Future research should focus on identification of biomarkers for a comprehensive diagnostic approach.

Aspirin-sensitive respiratory disease

Aspirin-sensitive respiratory disease (ASRD) is a condition characterized by persistent and often severe inflammation of the upper and lower respiratory tracts. Patients develop chronic eosinophilic rhinosinusitis, nasal polyposis, and asthma. The ingestion of aspirin and other cyclooxygenase-1 (COX-1) inhibitors induces exacerbations of airway disease that may be life-threatening. Thus, aspirin sensitivity is a phenotypic marker for the syndrome, yet nearly all affected individuals can be desensitized by the administration of graded doses of aspirin, leading to long-term clinical benefits. Patients with aspirin sensitivity are often able to tolerate selective COX-2 inhibitors. The pathogenesis of ASRD is underpinned by abnormalities in eicosanoid biosynthesis and eicosanoid receptor expression coupled with intense mast cell and eosinophilic infiltration of the entire respiratory tract. This review focuses on the molecular, cellular, and biochemical abnormalities characterizing ASRD and highlights unanswered questions in the literature and potential future areas of investigation.

Effect of in vitro aspirin stimulation on basophils in patients with aspirin-exacerbated respiratory disease

BACKGROUND

Basophil activation has been implicated in the pathogenesis of aspirin-exacerbated respiratory disease (AERD). However, a comprehensive analysis of basophil responses to aspirin in terms of mediator release, cytokine secretion and increased expression of surface activation markers has not been performed.

OBJECTIVE

To study the in vitro effects of aspirin on the concurrent release of histamine, leukotriene C4 (LTC4) and IL-4 from human basophils and to also evaluate changes in surface activation markers (CD63, CD69 and CD203c) expressed by these cells.

METHODS

Basophil-enriched cell suspensions from 10 patients with AERD and 10 healthy volunteers were incubated with lysine-aspirin for up to 3 h. Cells were analysed for expression of CD63, CD69 and CD203c using flow cytometry. Cell-free supernatants were evaluated for histamine, and LTC4 release and for IL-4 secretion.

RESULTS

Aspirin-induced expression of CD63, CD69 and CD203c yielded 30%, 80% and 70% sensitivity, respectively, but with poor specificity. There was no significant difference in LTC4 synthesis between groups. None of the patients with AERD (or controls) released IL-4 in response to aspirin. A higher dose of 5 mg/mL aspirin-mediated non-specific effects on basophils.

CONCLUSION

Basophil responses to in vitro aspirin challenge are poor indicators of clinical sensitivity. Aspirin activates some basophils by means of mechanisms that differ from the classical IgE-mediated pathway. Our study also shows that the use of 27 mm of aspirin (5 mg/mL) by previous investigators causes non-specific basophil activation, thereby eliminating its usefulness in a cell-based diagnostic test for AERD. Evaluation of in vitro basophil activation has low clinical value in identifying aspirin-induced respiratory reactions.

What do we know about the genetics of aspirin intolerance?

Although acetylsalicylic acid is prescribed for a broad range of diseases, it can induce a wide array of clinically recognized hypersensitivity reactions, including aspirin-intolerant asthma (AIA) with rhinitis and aspirin-intolerant urticaria (AIU) with anaphylaxis. Altered eicosanoid metabolism is the generally accepted mechanism of aspirin intolerance; the overproduction of cysteinyl leucotrienes has been suggested to play a causative role in both AIA and AIU. Genetic markers suggested for AIA include HLA-DPBI*0301, leucotriene C4 synthase (LTC4S), ALOX5, CYSLT, PGE2, TBXA2R and TBX21. Similarly, HLA-DB1*0609, ALOX5, FCER1A and HNMT have been identified as possible genetic markers for AIU. An additional low-risk genetic marker for AIA is MS4A2, which encodes the beta-chain of FCER1. Other single and sets of two or more interacting genetic markers are currently being investigated. Analyses of the genetic backgrounds of patients with AIA and AIU will promote the development of early diagnostic and therapeutic interventions, which may reduce the incidence of AIA and AIU.

Association of four-locus gene interaction with aspirin-intolerant asthma in Korean asthmatics

INTRODUCTION

Aspirin-intolerant asthma (AIA), a major clinical presentation of aspirin hypersensitivity, affects 10% of adult asthmatics. The genetic risk factors involved in the susceptibility to AIA have recently been investigated, but multilocus single-nucleotide polymorphisms (SNPs) associated with this susceptibility has not been evaluated.

METHODS

We examined 246 asthmatic patients: 94 having aspirin intolerance and 152 having aspirin tolerance. We selected 23 SNPs of 13 candidate genes and genotyped each SNP using a primer extension method. Multilocus genetic interactions were examined using multifactor dimensionality reduction (MDR) to test all multilocus SNP combinations to identify a useful SNP set for predicting the AIA phenotype.

RESULTS

We identified the best model using the MDR method, which consisted of a four-locus gene-gene interaction with 65.16% balanced accuracy and a cross-validation consistency of 70% in predicting AIA disease risk among asthmatic patients. This model included four SNPs such as B2ADR 46A>G, CCR3-520T>G, CysLTR1-634C>T, and FCER1B-109T>C.

DISCUSSION

These results suggest that a multilocus SNP acts in combination to influence the susceptibility to aspirin intolerance in asthmatics and could be a useful genetic marker for the diagnosis of AIA.

Lipoxin A4 levels in asthma: relation with disease severity and aspirin sensitivity

BACKGROUND

Lipoxin (LX) A4, an endogenous anti-inflammatory eicosanoid, has been found to be low in patients with severe asthma. However, few studies also suggested more diminished LX A4 levels in aspirin-exacerbated respiratory disease (AERD) when compared with aspirin-tolerant asthma (ATA). It is, therefore, currently not clear whether the asthma severity or the presence of AERD has a primary role in the disturbed LX metabolism.

OBJECTIVE

To detect LX A4 and 15-epi-LX A4 levels in asthma patients with and without AERD of comparable severity.

METHODS

The study groups consisted of 22 subjects with AERD, 22 subjects with ATA and 10 volunteers without asthma and aspirin sensitivity. Whole-blood samples were stimulated with calcium ionophore, A23187 (5 x 10(-5) m) and A23187 (5 x 10(-5) m)+aspirin (10(-4) m). LX A4 and 15-epi-LX A4 levels were analysed by the enzyme immune assay method.

RESULTS

Severe asthma patients in both AERD [0.5 (0.8)] ng/mL and ATA [0.5 (0.45) ng/mL] groups showed diminished generation for LX A4 to stimulation with A23187 in comparison with other severity degrees in their groups (P=0.02 and 0.046, respectively). LX A4 generation in both severe groups was comparable with each other (P>0.05). Although severe cases with AERD showed a diminished capacity to generate 15-epi-LX A4, this did not reach statistical significance.

CONCLUSION

This study indicated that diminished LX A4 generation was unique to severe asthma phenotype regardless of comorbid aspirin sensitivity. Clinical Implications Lower LX A4 levels in severe asthma would suggest a possibility for LX analogues as future treatment options in these patients.

EAACI/GA2LEN guideline: aspirin provocation tests for diagnosis of aspirin hypersensitivity

Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most common causes of adverse drug reactions. Majority of them are of the hypersensitivity type. The two frequent clinical presentations of aspirin hypersensitivity are: aspirin-induced bronchial asthma/rhinosinusitis (AIA/R) and aspirin-induced urticaria/angioedema (AIU). The decisive diagnosis is based on provocation tests with aspirin, as the in vitro test does not hold diagnostic value as yet. Detailed protocols of oral, bronchial and nasal aspirin provocation tests are presented. Indications, contraindications for the tests, the rules of drug withdrawal and equipment are reviewed. Patient supervision and interpretations of the tests are proposed.

Pathogenesis, diagnosis, and treatment of aspirin intolerance

OBJECTIVES

To provide an overview of aspirin intolerance (AI), to summarize the latest genetic and pathophysiologic findings, and to discuss the current therapeutic recommendations, including aspirin desensitization.

DATA SOURCES

Using the PubMed database, a systematic search of articles published between 1968 and 2006 was performed to evaluate the current literature on AI. The bibliographies of selected articles served as a source of additional literature.

STUDY SELECTION

Included articles were selected for their relevance to the pathogenesis, diagnosis, and management of AI.

RESULTS

The prevalence of AI is approximately 0.3% to 0.9%, but AI is often overlooked. It can display a wide range of clinical pictures, such as acute asthma attacks, urticaria, angioedema, chronic rhinitis, myocardial ischemia, and anaphylactic shock. Regarding the pathogenesis of AI, modifications of eicosanoid metabolism are supposed to underlie AI, including aspirin-induced asthma and aspirin-induced urticaria. However, the pathogenesis of AI has not yet been clearly elucidated. Associations of several HLA alleles with subtypes of AI, such as aspirin-induced urticaria and aspirin-induced asthma, and single nucleotide polymorphisms in genes encoding enzymes involved in arachidonic acid metabolism have been shown.

CONCLUSIONS

Because aspirin therapy should be avoided in AI patients, the use of alternative drugs is recommended. Patients intolerant of alternative drugs and those with therapy-resistant asthma or sinusitis benefit from aspirin desensitization.