An update on the management of aspirin-exacerbated respiratory disease

Association of eosinophil-derived neurotoxin levels with asthma control status in patients with aspirin-exacerbated respiratory disease

BACKGROUND

The long-term goals of asthma treatment are to achieve well control of symptoms and to minimize the future risk of asthma exacerbation. Identifying biomarkers for uncontrolled asthma is important for improving the asthma outcome. This study aimed to investigate the association of the levels of eosinophil-derived neurotoxin (EDN) with asthma control status in specific asthma phenotype, aspirin-exacerbated respiratory disease (AERD), and aspirin-tolerant asthma (ATA).

METHODS

A total of 136 adult asthmatics, including 47 asthmatics with AERD and 89 asthmatics with ATA, were enrolled. Plasma, sputum, and urine were collected at enrollment and the levels of EDN were measured by the K-EDN ELISA kit. Urinary leukotriene E4 (LTE4 ) level was measured using liquid chromatography-mass spectrometry (LC-MS)/MS methods. Asthma control status was evaluated according to the GINA guideline, asthma control test and asthma control questionnaire scores.

RESULTS

In the total study subjects, sputum levels of EDN as well as of urine and plasma EDN showed significantly higher levels in patients with uncontrolled asthma than in those with well-controlled or partly-controlled asthma (ANOVA, p < 0.001); in patients with AERD, the sputum EDN levels showed significant correlations with ACT, ACQ, and AQLQ scores (p = 0.010, r = -0.536, p = 0.001, r = 0.665, and p < 0.001, r = -0.691, respectively), while no differences were noted in patients with ATA. Sputum EDN level was the only significant factor for ACT, ACQ, and AQLQ scores in patients with AERD (p = 0.001, p < 0.001, and p < 0.001, respectively) in the multivariate analysis adjusting for age, sex, peripheral eosinophil count, and urine LTE4 . The ROC curve analysis demonstrated that sputum EDN can predict uncontrolled asthma with 80% sensitivity and 88.2% specificity for ACT ≤ 19 (area under the ROC curve [AUC] = 0.824, p = 0.019); 71.4% sensitivity and 86.7% specificity for ACQ ≥ 1.5 (AUC = 0.752, p = 0.049) only in AERD patients.

CONCLUSION

The level of sputum EDN may be a potential biomarker for identifying the asthma control status in patients with AERD.

Aspirin desensitization in nonsteroidal anti-inflammatory exacerbated respiratory disease: The first prospective cohort in Chile

Background

Nonsteroidal anti-inflammatory exacerbated respiratory disease (N-ERD) is characterized by the Samter triad: chronic rhinosinusitis with nasal polyps, asthma, and nonallergic hypersensitivity to NSAIDs. Its diagnosis is based on a complete clinical history and an aspirin (ASA) challenge test. Medical treatments include biological drugs and ASA desensitization.

Objective

This study aims to evaluate the clinical response of patients with N-ERD undergoing functional endoscopic surgery (FES), followed by ASA desensitization and maintenance treatment, being the first prospective cohort study carried out in Chile.

Methods

We conducted 1-year follow-up of 12 patients with N-ERD treated with FES, desensitization, and maintenance with ASA. For each control, the medication score, sinonasal symptomatology (SNOT-22), PEF (peak expiratory flow), nasal polyposis (Lildholdt score), and the appearance of adverse effects were recorded. Computed tomography (CT) of the paranasal cavities was performed at baseline and at the 12-month follow-up to calculate the Lund-Mackay score.

Results

Patients presented a reduction of SNOT-22 after the FES, which was maintained at 12 months (p = 0.002); the symptoms that showed the greatest reduction were feeling embarrassed and nasal obstruction. The Lildholdt score was also significantly reduced (p = 0.001); in only three patients, the nasal polyps recurred, and all were small. The PEF showed a slight nonsignificant increase of 3.3%. In total, 75% of patients had an adverse effect, the most frequent being abdominal pain (66.7%), but none of the 12 patients required discontinuation of aspirin treatment in 1-year follow-up. The Lund-Mackay score had a significant reduction of 6.6 points (p < 0.001).

Conclusion

ASA desensitization is safe and effective in reducing upper and lower respiratory symptoms in patients with N-ERD and delays the reappearance of nasal polyps, although it is not exempt from adverse effects, with the vast majority being mild.

An Overview of Off-Label Use of Humanized Monoclonal Antibodies in Paediatrics

In recent years, off-label and unlicensed drug use has extensively developed in the paediatric population. For a long time, clinical trials in the paediatric population were considered complicated to perform because of ethical problems, causing frequent off-label use. Off-label drug use remains an important public health issue, especially for children with rare conditions or with diseases not responsive to conventional treatments. The present paper is a narrative review of the literature of off-label drug use in children. The aim of our study is to summarize the main works dealing with the off-label use of biological drugs in paediatrics. Further studies analyzing their efficacy, safety, and cost-benefit ratios are needed to extend the use of biological therapies to the paediatric population.

Persistent Eosinophilic Inflammation in Adult Asthmatics with High Serum and Urine Levels of Leukotriene E4

Background

Cysteinyl leukotrienes (CysLTs) are key mediators for bronchoconstriction, eosinophil recruitment and mucus production in the airways of asthmatic patients. To better understand the role of CysLTs in different asthma phenotypes, we compared the levels of arachidonic acid metabolites in relation to asthma control status and phenotypes in adult asthmatics on regular anti-asthma medications.

Methods

A total of 137 adult asthmatics (47 with aspirin-exacerbated respiratory disease [AERD] and 90 asthmatics with aspirin-tolerant asthma [ATA]) and 20 healthy controls were enrolled. Arachidonic acid metabolites in serum and urine were analyzed using LC-MS/MS methods, and clinical data, including asthma control status, exhaled NO (FeNO) and lung function tests, were collected.

Results

Urine LTE₄ levels were significantly higher in AERD patients on inhaled corticosteroid-long-acting β₂- agonist plus leukotriene receptor antagonist (LTRA) treatment than in ATA patients (P=0.001). No differences were found in the serum or urine levels of 15-HETE, TXB_2, or PGF_2α. High serum LTE₄ levels were associated with lower FEV1% and uncontrolled status in AERD patients (P=0.006 and P=0.002, respectively), but not in ATA patients. Multivariate analysis demonstrated that blood eosinophil counts, FeNO levels and aspirin hypersensitivity were significant factors affecting urine LTE₄ levels.

Conclusion

Despite LTRA treatment in AERD, the LTE₄ levels remained high and showed close associations with blood eosinophilia, high FeNO levels and impaired disease control. Our real-world evidence indicates that control of asthma is not fully achieved by blocking the CysLT pathway with LTRA. Thus, introduction of treatment modalities targeting eosinophilia could be a better option for patients with high CysLTs.

Administration of vitamin E attenuates airway inflammation through restoration of Nrf2 in a mouse model of asthma

Accumulating evidence reveals that ROS is one of the key mediators that contribute to the development of asthma. Studies on antioxidants have shown to have beneficial effects on asthma management. However, we still do not know the precise mechanism, and the effects depend on age. This study was conducted to assess the levels of ROS and the effect of antioxidants in younger and older mice using an eosinophilic asthma model. We analyzed airway hyperresponsiveness (AHR), cytokines in bronchoalveolar lavage fluid (BALF), inflammatory cell counts, and the expression levels of NFκB, Nrf2, EPx, and EDN in the lung tissue, as well as the level of ROS in the lung tissue and BALF. The degree of eosinophilia and the levels of IL-5, ROS, and NFκB were significantly increased, whereas the endogenous levels of vitamin E and Nrf2 were decreased in the lung and BALF in the older mice compared to younger mice. The administration of vitamin E attenuated AHR, airway inflammation, and the level of IL-13 and ROS and enhanced the Nrf2 level in the older mice compared to the younger mice. Taken together, vitamin E treatment may have the therapeutic potential through restoration of the Nrf2 level, especially in elderly asthma.

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.

Current and Future Treatments of Rhinitis and Sinusitis

Advances in understanding the pathogenic mechanisms of both rhinitis and chronic rhinosinusitis have resulted in new treatment options, especially for chronic rhinosinusitis. A review of relevant medical and surgical clinical studies shows that intranasal corticosteroids, antihistamines, and allergen immunotherapy continue to be the best treatments for chronic rhinitis. Dupilumab is the first biologic approved for chronic rhinosinusitis with polyps. Omalizumab, mepolizumab, and benralizumab may have a future role in the treatment of chronic rhinosinusitis. Novel corticosteroid delivery devices such as an exhalation delivery system for fluticasone and bioabsorbable sinus implants provide enhanced and localized distribution of corticosteroids. Surgical management tailored to the underlying disease process improves clinical outcomes in chronic rhinosinusitis with or without nasal polyposis. Advances in the understanding of the heterogeneous nature of rhinitis and rhinosinusitis have resulted in more precise treatments. Improving the understanding of different endotypes should provide better knowledge to determine appropriate current and new therapies to treat these diseases.

Update on the Management of Nonsteroidal Anti-Inflammatory Drug Hypersensitivity

The clinical phenotypes of nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity are heterogeneous with various presentations including time of symptom onset, organ involvements, and underlying pathophysiology. Having a correct diagnosis can be challenging. Understanding their respective mechanisms as well as developing a comprehensive classification and diagnostic algorithm are pivotal for appropriate management strategy. Treatment modalities are based on the subtypes and severity of hypersensitivity reactions. Insights into the phenotypes and endotypes of hypersensitivity reactions enable personalized management in patients with suboptimal control of disease. This review updated the recent evidence of pathophysiology, classification, diagnostic algorithm, and management of NSAID hypersensitivity reactions.

Asthma pharmacotherapy: an update on leukotriene treatments

Introduction: Asthma is a chronic inflammatory disease of the airways with a large heterogeneity of clinical phenotypes. There has been increasing interest regarding the role of cysteinyl leukotriene (LT) and leukotriene receptor antagonists (LTRA) in asthma treatment.Areas covered: This review summarized the data (published in PubMed during 1984-2019) regarding LTRA treatment in asthma and LTs-related airway inflammation mechanisms. Involvement of LTs C₄/D₄/E₄ has been demonstrated in the several aspects of airway inflammation and remodeling. Novel pathways related to LTE₄, the most potent mediator, and its respective receptors have recently been studied. Antagonists against cysteinyl leukotriene receptor (CysLTR) type 1, including montelukast, pranlukast and zafirlukast, have been widely prescribed in clinical practices; however, some clinical trials have shown insignificant responses to LTRAs in adult asthmatics, while some phenotypes of adult asthma showed more favorable responses to LTRAs including aspirin-exacerbated respiratory disease, elderly asthma, asthma associated with smoking, obesity and allergic rhinitis.Expert opinion: Further investigations are needed to understand the role of LTs in airway inflammation and remodeling of the asthmatic airways. There is a lack of biomarkers to predict responsiveness to LTRA, especially in adult asthmatics. Besides CysLTR1 antagonists, targets aiming other LT pathways should be considered.

Which Factors Associated With Activated Eosinophils Contribute to the Pathogenesis of Aspirin-Exacerbated Respiratory Disease?

Eosinophils have long been recognized as a central effector cell in the lungs of asthmatic patients. They contribute to airway inflammation and remodeling through releasing several molecules such as cytokines, granule proteins, lipid mediators and extracellular traps/vesicles. Repeated evidence reveals that intense eosinophil infiltration in upper and lower airway mucosae contributes to the pathogenesis of aspirin-exacerbated respiratory disease (AERD). Persistent eosinophilia is found to be associated with type 2 immune responses, cysteinyl leukotriene overproduction and eosinophil-epithelium interactions. This review highlights recent findings about key mechanisms of eosinophil activation in the airway inflammation of AERD. In addition, current biologics (targeting type 2 immune responses) were suggested to control eosinophilic inflammation for AERD patients.