Immunomodulatory treatments for aspirin exacerbated respiratory disease

Differential Diagnosis of Asthma

Asthma is one of the most common chronic syndromes worldwide (Moorman et al., Vital Health Stat 3(35), 2012). It is not a diagnosis but a clinical syndrome based on a constellation of signs and symptoms (Li et al., Ann Allergy Asthma Immunol 81:415–420(IIa), 1998). The classic symptoms of asthma include chest tightness, wheeze, cough, and dyspnea (Moorman et al., Vital Health Stat 3(35), 2012). The term asthma encompasses a spectrum of pulmonary diseases sharing the hallmark of reversible airway obstruction and can be classified as allergic or non-allergic (Löwhagen, J Asthma. 52(6):538–44, 2015). Asthma designated allergic is due to an immunoglobulin E (IgE)-mediated process, but as noted not all asthma is allergic in etiology (Romanet-Manent et al., Allergy 57:607–13, 2002). The differential diagnosis for asthma is broad and requires a detailed history with supportive pulmonary function tests to be properly diagnosed.

Prostaglandin E2 in NSAID-exacerbated respiratory disease: protection against cysteinyl leukotrienes and group 2 innate lymphoid cells

PURPOSE OF REVIEW

The purpose of this review is to describe the recent advances that have been made in understanding the protective role of prostaglandin E2 (PGE2) in aspirin-exacerbated respiratory disease (AERD), known in Europe as NSAID-exacerbated respiratory disease (N-ERD).

RECENT FINDINGS

Decreased PGE2 signaling through the EP2 receptor in patients with AERD leads to an increase in leukotriene synthesis and signaling. Leukotriene signaling not only directly activates group 2 innate lymphoid cells and mast cells, but it also increases production of IL-33 and thymic stromal lymphopoietin. These cytokines drive Th2 inflammation in a suspected feed-forward mechanism in patients with AERD.

SUMMARY

Recent discoveries concerning the role of PGE2 in leukotriene synthesis and signaling in AERD, as well as downstream effects on group 2 innate lymphoid cells and mast cells, allow for a more comprehensive understanding of the pathogenesis of this disease. These discoveries also identify new paths of potential investigation and possible therapeutic targets for AERD.

Epithelial folliculin enhances airway inflammation in aspirin-exacerbated respiratory disease

BACKGROUND

Clinical features of aspirin-exacerbated respiratory disease (AERD) are characterized by overproduction of cysteinyl leukotrienes (LT) and eosinophil activation, in which epithelial cells contribute to eosinophilic airway inflammation. Folliculin (FLCN) helps maintain the integrity of epithelial barrier, but little is known about FLCN in AERD.

OBJECTIVE

We investigated the role of FLCN in the pathogenic mechanisms of AERD.

METHODS

We recruited 178 subjects with AERD, 276 subjects with aspirin-tolerant asthma (ATA) and 71 normal healthy controls (NC) at Ajou Medical Center. Levels of FLCN and interleukin (IL)-8 in sera and supernatants were measured by ELISA. Peripheral blood eosinophils isolated from asthmatic patients were cocultured with human airway epithelial cells (HAECs) pretreated with LTE₄ , dexamethasone and montelukast. The intracellular expressions of FLCN, tight (TJ) (occludins, claudin-1) and adherens (AJ) junctions (E-cadherin) were analysed by Western blotting. shRNA was used to down-regulate FLCN (shFLCN) in HAECs.

RESULTS

Serum FLCN levels were significantly higher in AERD group than in ATA and NC groups (all P < 0.001). The cut-off value of 56.6 pg/mL was used to define the high FLCN phenotype (highFLCN). Asthmatic patients with highFLCN were associated with increased airway hyperresponsiveness to methacholine (P = 0.015). The serum FLCN level could discriminate AERD group from NC group with 82% sensitivity (AUC = 0.793, P < 0.001). When HAECs were exposed to LTE₄ , FLCN release was increased significantly (P < 0.05), which were amplified along with disruption of TJ and AJ expressions when HAECs were cocultured with eosinophils and LTE₄ (all P < 0.05); these effects were suppressed by dexamethasone and montelukast. FLCN knockdown reduced IL-8 release and occludin expression from shFLCN HAECs.

CONCLUSIONS

Our findings suggest that high LT and airway eosinophilia increased FLCN release from HAECs, which enhance epithelial activation and disruption. Modulation of FLCN may be a potential target for AERD.

[The use of intranasal glucocorticosteroids in the treatment of rhinosinusitis: Focus on mometasone furoate]

The authors discuss the mechanism of action, effectiveness, and safety of intranasal glucocorticosteroids (inGCS) used to treat acute, recurrent and chronic rhinosinusitis (RS). The last version of the European guidelines concerning the application of inGCS assigns the highest level of evidence-Ia and the highest strength of recommendations-A to these medications when applied for the treatment of acute and polypoid rhinosinusitis. Moreover, they acquire the status of the agents of choice for the therapy of chronic RS without polyps. Mometasone furoate is one of the best explored preparations of this group of medicines. It is possessed of favourable pharmacodynamic and pharmacokinetic properties when prescribed for local application. The new mometasone furoate preparation in the form of an intranasal spray Dezrinit produced by "Teva" Ltd. was registered in the Russian Federation. In a comparative randomized clinical trial (RCT), the preparation was shown to be an equivalent to the Nasonex spray.

Contemporary management of chronic rhinosinusitis with nasal polyposis in aspirin-exacerbated respiratory disease: an evidence-based review with recommendations

BACKGROUND

Chronic rhinosinusitis (CRS) in aspirin-exacerbated respiratory disease (AERD) represents a recalcitrant form of sinonasal inflammation for which a multidisciplinary consensus on patient management has not been reached. Several medical interventions have been investigated, but a formal comprehensive evaluation of the evidence has never been performed. The purpose of this article is to provide an evidence-based approach for the multidisciplinary management of CRS in AERD.

METHODS

A systematic review of the literature was performed and the guidelines for development of an evidence-based review with recommendations were followed. Study inclusion criteria included: adult population >18 years old; CRS based on published diagnostic criteria, and a presumptive diagnosis of AERD. We focused on reporting higher-quality studies (level 2 or higher) when available, but reported lower-quality studies if the topic contained insufficient evidence. Treatment recommendations were based on American Academy of Otolaryngology (AAO) guidelines, with defined grades of evidence and evaluation of research quality and risk/benefits associated with each treatment.

RESULTS

This review identified and evaluated the literature on 3 treatment strategies for CRS in AERD: dietary salicylate avoidance, leukotriene modification, and desensitization with daily aspirin therapy.

CONCLUSION

Based on the available evidence, dietary salicylate avoidance and leukotriene-modifying drugs are options following appropriate treatment with nasal corticosteroids and saline irrigation. Desensitization with daily aspirin therapy is recommended following revision endoscopic sinus surgery (ESS).

Evidence-based treatment of chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNPs) is the most challenging form of CRS to treat. Clinical practices vary widely among physicians around the world, often with little evidence to support current therapies.

METHODS

This study evaluates various medical and surgical treatments with a focus on the highest levels of evidence. Recommendations for various therapies are provided based on consensus panels and evidence-based reviews.

RESULTS

Therapies with the strongest evidence and recommendations for CRSwNPs include oral steroids and topical nasal steroid sprays. There is also reasonable evidence for surgery, to include perioperative oral steroids and postoperative oral antibiotics for at least 2 weeks. There is little evidence to support other therapies, including commonly used modalities such as oral antibiotics, antihistamines, and immunotherapy.

CONCLUSION

CRSwNPs is a heterogenous disorder that currently has very few therapies supported by strong evidence. It is likely that in the near future, a more refined understanding of CRSwNPs will permit clinicians to tailor therapies using high-level evidence with improved outcomes.

Long-term sinonasal outcomes of aspirin desensitization in aspirin exacerbated respiratory disease

OBJECTIVE

This study aimed to assess sinonasal outcomes in patients with aspirin exacerbated respiratory disease (AERD) undergoing aspirin desensitization following endoscopic sinus surgery (ESS).

STUDY DESIGN

Case series with chart review.

SETTING

University hospital.

SUBJECTS AND METHODS

A retrospective review of sinonasal outcomes was conducted for 30 AERD patients undergoing aspirin desensitization and maintenance therapy following ESS. Sinonasal outcomes were prospectively assessed by the Sinonasal Outcomes Test-22 (SNOT-22) and endoscopic polyp grading system. Data were collected preoperatively, 1 and 4 weeks postsurgery (before desensitization), and 1, 6, 12, 18, 24, and 30 months after aspirin desensitization.

RESULTS

Twenty-eight of 30 patients (93.3%) successfully completed aspirin desensitization, whereas 2 of 30 (6.7%) were unable to complete desensitization due to respiratory intolerance. Of the 21 patients who successfully completed a minimum of 24 weeks of follow-up, 20 (95.2%) patients demonstrated sustained endoscopic and symptomatic improvement for a median follow-up period of 33 months. After surgical treatment but before desensitization, patients experienced significant reductions in SNOT-22 and polyp grade scores. In the first 6 months after aspirin desensitization, patients experienced further significant reductions in SNOT-22 scores, whereas polyp grade remained stable. The improvements in symptom endoscopic scores were preserved throughout the follow-up period after desensitization. No patients required additional sinus surgery. One patient had to discontinue aspirin therapy due to gastrointestinal side effects. No other adverse reactions to aspirin were noted.

CONCLUSION

Aspirin desensitization following ESS appears to be a well-tolerated and effective adjunctive therapy for long-term control of nasal polyposis in patients with AERD.

Aspirin desensitization in patients with aspirin-induced and aspirin-tolerant asthma: a double-blind study

BACKGROUND

Numerous open trials have demonstrated the beneficial clinical effects of aspirin desensitization (AD) in patients with aspirin-induced asthma (AIA). These beneficial effects might be attributable to aspirin's potent anti-inflammatory properties, but that supposition requires further corroboration.

OBJECTIVE

We sought to compare the clinical and biochemical responses to chronic oral AD in 20 patients with AIA and 14 patients with aspirin-tolerant asthma (ATA). All of the patients had chronic rhinosinusitis and nasal polyposis, and these responses were investigated in a pilot, double-blind, placebo-controlled study.

METHODS

Twelve patients with AIA and 6 patients with ATA were randomly assigned to receive 624 mg of aspirin, and 8 patients with AIA and 8 patients with ATA received placebo. Both aspirin and placebo were administered once daily for 6 months. Nasal symptoms, Sino-Nasal Outcome Test (SNOT20) scores, peak nasal inspiratory flows, Asthma Control Questionnaire scores, spirometric parameters, peak expiratory flows, blood eosinophilia, and corticosteroid doses were assessed on a monthly basis. Levels of urinary leukotriene E4 and the stable plasma prostaglandin (PG) D2 metabolite 9α,11β-PGF2 were evaluated at baseline and after 1, 3, 5, and 6 months.

RESULTS

Only the patients with AIA subjected to AD reported improvements in smell and reductions in sneezing and nasal blockade. The SNOT20 and Asthma Control Questionnaire scores of these patients decreased, and their peak nasal inspiratory flows increased. The dosages of inhaled corticosteroids were reduced. There were no changes in leukotriene E(4) or 9α,11β-PGF(2) levels after AD.

CONCLUSION

The clinically beneficial effects of AD on nasal and bronchial symptoms occurred only in the patients with AIA.

Chapter 6: Nasal polyps

Nasal polyps occur in 1-4% of the population, usually occurring in the setting of an underlying local or systemic disease. The most common associated condition is chronic rhinosinusitis (CRS). A high prevalence of nasal polyps is also seen in allergic fungal rhinosinusitis, aspirin-exacerbated respiratory disease, Churg-Strauss syndrome, and cystic fibrosis. In the setting of CRS, nasal polyps are not likely to be cured by either medical or surgical therapy; however, control is generally attainable. The best medical evidence supports the use of intranasal corticosteroids for maintenance therapy and short courses of oral corticosteroids for exacerbations. The evidence for short- and long-term antibiotics is much less robust. For patients with symptomatic nasal polyposis nonresponsive to medical therapies, functional endoscopic sinus surgery provides an adjunctive therapeutic option.

Leukotriene antagonists in nasal polyposis: a meta-analysis and systematic review

BACKGROUND

Leukotriene antagonists (LTAs) provide a potential strategy for the management of chronic rhinosinusitis with nasal polyposis (CRSwNP), which is often refractory to medical and surgical treatment. The purpose of this study is to determine the impact of LTA treatment alone and in conjunction with intranasal corticosteroids (INCSs) on nasal symptoms, objective clinical outcomes, and immune parameters in CRSwNP.

METHODS

A systematic review was performed including studies that assessed the effectiveness of LTAs on clinical outcome measures of CRSwNP. Exclusion criteria were trials assessing LTAs in CRS without nasal polyps or asthma symptoms only. Quantitative analysis was performed using a random effects model.

RESULTS

Twelve studies fulfilled eligibility: five randomized control trials and seven case series. LTAs showed significant improvements in CRSwNP symptoms over placebo; however, these randomized trials were unable to be combined via meta-analysis. The two studies used in meta-analysis showed a standardized mean difference of pooled overall symptom scores of 0.02 (95% confidence interval, -0.39-0.44) between LTA and INCS study arms, indicating no difference between the treatment modalities. Improvement was described by all studies in symptoms, clinical outcomes, and/or immune parameters after LTA treatment, with greater improvements in a subset of symptoms beyond that observed with INCSs. Concomitant asthma, aspirin-exacerbated respiratory disease, and atopy did not significantly or consistently affect these results.

CONCLUSION

LTAs are an effective tool for treating CRSwNP, with limited benefit as an adjunctive therapy. Additional study is required to determine the most beneficial strategy and patient population for their use.

Other asthma considerations

Asthma is a heterogeneous syndrome of cough, wheeze, dyspnea, and chest tightness. However, in a subset of patients, these symptoms may indicate a different underlying disease process with variable responsiveness to classic asthma therapies. Disease may progress while practitioners attempt conventional asthma therapy. Additionally, some types of asthma may require alternative approaches to relieve symptoms successfully. This article describes the differential diagnosis of asthma and discusses some of the more common asthma variants and asthma mimickers.

Systemic prednisone administration selectively alters granulocyte subsets in nasal polyps from aspirin-exacerbated respiratory disease and chronic rhinosinusitis patients

BACKGROUND

Nasal polyps (NPs) are hallmark inflammatory lesions of sinusitis. Despite the spectrum of NP conditions, cellular differences between NPs from patients with chronic rhinosinusitis with NPs (CRSwNP) and aspirin-exacerbated respiratory disease (AERD) are poorly understood. NPs are associated with abundant eosinophils; the contributions of neutrophil and basophil granulocytes are less defined. We therefore sought to assess granulocyte subpopulations, and differential effects following prednisone pretreatment, within NPs of CRSwNP and AERD patients.

METHODS

NPs, adjacent ethmoid sinus tissue, and peripheral blood mononuclear cells (PBMCs) were obtained from patients undergoing endoscopic sinus surgery. Samples from 5 cohorts: CRSwNP ± prednisone (n = 6 each), AERD ± prednisone (n = 6 each), and controls (n = 9), were analyzed by high-dimensional flow cytometry to gate granulocyte populations. Specimens were also assessed using immunohistochemistry (IHC) staining.

RESULTS

Systemic prednisone administration was associated with a lower frequency of eosinophils (p < 0.0001, n = 6) in NPs in both CRSwNP and AERD patients, whereas a decrease in neutrophils (p = 0.0070, n = 6) in NPs was only observed in CRSwNP patients after prednisone treatment. In contrast, steroids do not alter basophil proportions (p = 0.48, n = 6) within NPs from either group. No significant shift in granulocyte subsets after steroid treatment was identified in the adjacent ethmoid mucosa or PBMCs from the same patients. Immunohistochemistry (IHC) staining supported these findings.

CONCLUSION

Granulocyte subpopulations are focally affected within NPs by systemic steroid exposure, without notable granulocyte alterations in the surrounding regional tissues. These data provide direct insights into the cellular effects of routine prednisone exposure in CRS patients, and highlight a unique microenvironment present within NP lesions.

Subclassification of chronic rhinosinusitis

OBJECTIVES/HYPOTHESIS

There are variants of chronic rhinosinusitis (CRS). Therefore, the objectives of this study were to phenotype the subclasses of CRS as well as characterize their polyps with histology and cellular-intracellular biomarkers.

STUDY DESIGN

Prospective case-control study.

METHODS

Demographic data, quality-of-life (QoL) questionnaires, nasal endoscopy (NE), and computed tomography (CT) scores were obtained. CRS was divided into seven subclasses: aspirin-exacerbated respiratory disease (AERD), asthmatic sinusitis with and without allergy, nonasthmatic sinusitis with and without allergy, allergic fungal sinusitis (AFS), and cystic fibrosis (CF). Histopathologic and immunohistochemistry of nasal polyps were recorded. CD3, CD4, CD8, CD19, CD45, and CD56 data were collected. Interleukin (IL)4, IL5, IL13, IL17, and interferon (IFN)-γ were measured.

RESULTS

Eight-four subjects were in this study. Two QoL questionnaires were inadequate at distinguishing the control group from CRS. NE and CT were able to differentiate between the control group and all CRS subclasses (P<.01). Asthmatic sinusitis, AERD, and AFS had high NE and CT scores, nasal polyps, eosinophils, mast cell, and hypercellularity. Asthmatic sinusitis, nonasthmatic sinusitis, and AERD had higher CD4 cells than control group (P<.05). Even though asthmatic sinusitis and AFS are mediated by Th2, AFS had differing levels of Th2 cytokines. Each nonasthmatic sinusitis had purulence and low CT score. Each nonasthmatic sinusitis had higher CD4 cells and IFN-γ than control (P<.05). CF is associated with purulence, high CT score, high polymorphonuclear leukocytes, high plasma cells, and high mast cells.

CONCLUSIONS

Well-characterized and distinct groups of CRS have been defined for targeted treatment and research studies.