Corticosteroid treatment regulates mucosal remodeling in chronic rhinosinusitis with nasal polyps

Matrix metalloproteinases in chronic rhinosinusitis

INTRODUCTION

Matrix metalloproteinases (MMPs) are a group of enzymes that are essential in maintaining extracellular matrix (ECM) homeostasis, regulating inflammation and tissue remodeling. In chronic rhinosinusitis (CRS), the overexpression of certain MMPs can contribute to chronic nasal tissue inflammation, ECM remodeling, and tissue repair.

AREAS COVERED

This review provides a comprehensive overview of the biological characteristics and functions of the MMP family, particularly focusing on the expression and activity of MMPs in patients with CRS, and delves into their role in the pathogenesis of CRS and their potential as therapeutic targets.

EXPERT OPINION

MMPs are important in tissue remodeling and have been implicated in the pathophysiology of CRS. Previous studies have shown that the expression of MMPs is upregulated in the nasal mucosa of patients with CRS and positively correlates with the severity of CRS. However, there is still a large gap in the research content of MMP in CRS, and the specific expression and pathogenic mechanism of MMP still need to be clarified. The significance and value of the ratio of MMP to tissue inhibitors of metalloproteinase (TIMP) in diseases still need to be demonstrated. Moreover, further studies are needed to assess the efficacy and safety of biologics that target MMPs in patients with CRS.

Association of Comorbid Asthma and the Efficacy of Bioabsorbable Steroid-eluting Sinus Stents Implanted After Endoscopic Sinus Surgery in Patients with Chronic Rhinosinusitis with Nasal Polyps

OBJECTIVE

To identify factors affecting the efficacy of steroid-eluting sinus stents implanted after endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODS

We performed a post-hoc analysis of a randomized self-controlled clinical trial on post-operative implantation of bioabsorbable steroid-eluting stents in patients with CRSwNP. Univariate logistic regression analysis was conducted to identify which of the following factors affect the response to post-operative stent implantation: sex, serum eosinophil levels, history of prior surgery, endoscopic scores, and comorbid conditions (asthma and allergic rhinitis). The primary outcome was the rate of post-operative intervention on day 30, and the secondary outcome was the rate of polypoid tissue formation (grades 2-3) on days 14, 30, and 90.

RESULTS

A total of 151 patients with CRSwNP were included in the post-hoc analysis. Asthma was identified as the only risk factor for a poor response to steroid-eluting sinus stents on post-operative day 30, with an odds ratio of 23.71 (95% CI, 2.81, 200.16; P=0.004) for the need for post-operative intervention and 19 (95% CI, 2.20, 164.16; P=0.003) for moderate-to-severe polypoid tissue formation. In addition, the asthmatic group showed higher rates of post-operative intervention and polypoid tissue formation than the non-asthmatic group on post-operative day 30. Blood eosinophil levels were not identified as a risk factor for poor outcomes after stent implantation.

CONCLUSION

Comorbid asthma, but not blood eosinophil level, impairs the efficacy of steroid-eluting sinus stents in the short term after ESS in patients with CRSwNP.

Pathogenesis and treatment of chronic rhinosinusitis from the perspective of sinonasal epithelial dysfunction

Background

Chronic rhinosinusitis (CRS) is a clinical syndrome primarily characterized by long-term mucosal inflammation of the nasal cavity and sinuses. The pathogenesis of CRS is still unclear due to its high heterogeneity. A number of studies have recently focused on the sinonasal epithelium. Thus, there has been a quantum leap in awareness of the role of the sinonasal epithelium, which is now understood as an active functional organ rather than simply an inert mechanical barrier. Undoubtedly, epithelial dysfunction plays a vital role in the onset and development of CRS.

Objective

In this article, we discuss the potential contribution of sinonasal epithelium dysfunction to CRS pathogenesis and explore a few current and developing therapeutic options targeting the sinonasal epithelium.

Results

Impaired mucociliary clearance (MCC) and an abnormal sinonasal epithelial barrier are usually considered to be the main causative factors in CRS. Epithelial-derived bioactive substances, such as cytokines, exosomes, and complements, play a vital role in the regulation of innate and adaptive immunity and contribute to the pathophysiological alterations of CRS. The phenomena of epithelial-mesenchymal transition (EMT), mucosal remodeling, and autophagy observed in CRS offer some novel insights into the pathogenesis of this disease. In addition, existing treatment options targeting disorder of sinonasal epithelium can help to relieve the main symptoms associated with CRS to some extent.

Conclusion

The presence of a normal epithelium is fundamental for maintaining homeostasis in the nasal and paranasal sinuses. Here, we describe various aspects of the sinonasal epithelium and highlight the contributions of epithelial dysfunction to CRS pathogenesis. Our review provides sound evidence of the need for in-depth study of the pathophysiological alterations of this disease and for the development of novel epithelium-targeting alternative treatments.

Sinonasal Outcomes Using Oral Corticosteroids in Patients with Chronic Rhinosinusitis with Nasal Polyps and Positive Sinonasal Cultures

Introduction Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and positive sinonasal bacterial cultures may be recalcitrant to topical therapy alone due to the additional local inflammatory burden associated with bacterial infection/colonization.

Objective To evaluate sinonasal outcomes in CRSwNP patients with a positive perioperative bacterial culture, who were treated with postoperative intranasal corticosteroids (INCS) alone versus INCS in combination with a short-term course of oral corticosteroids (OCS).

Methods This is a retrospective chart review of CRSwNP patients. A total of 59 patients met inclusion criteria, including positive perioperative bacterial culture and treatment with INCS with or without concomitant use of OCS. Two cohorts were formed based on the chosen postoperative medical treatment; 32 patients underwent postoperative INCS alone, while 27 underwent INCS plus a ≤ 2-week course of OCS. The 22-item sinonasal outcome test (SNOT-22) scores and Lund-Kennedy scores (LKS) were assessed preoperatively, and at 2-week, 4-week, and 4 to 6 months after endoscopic sinus surgery (ESS).

Results There were no statistically significant differences in postoperative sinonasal symptoms or endoscopic scores between the cohorts treated with INCS plus OCS versus those prescribed INCS alone (p > 0.05). Our regression model failed to demonstrate a relationship between the use of OCS and better sinonasal outcomes at 2-week, 4-week, and 4 to 6 months after ESS (p > 0.05).

Conclusion Our study suggests that in a cohort of CRSwNP patients with recent bacterial infections, the postoperative use of combined OCS and INCS did not result in a statistical improvement of endoscopic and symptomatic outcomes over INCS irrigation alone. However, both treatment groups had a clinically significant improvement based on the Minimal Clinically Important Difference.

Atopy as a specific predictor of response to systemic and local steroid therapy in patients with chronic rhinosinusitis without nasal polyps

<b>Introduction:</b> Studies on the pathophysiology of chronic rhinosinusitis have shown an effect of IgE antibodies on the course of the disease, as well as the effectiveness of treatment. Steroid therapy remains the most prevailing method of CRS treatment. </br></br> <b>Aim: </b>The aim of our study was to determine the clinical response to systemic and local steroid therapy in patients with CRSsNP depending on the total IgE antibody serum concentration. </br></br> <b>Material and methods:</b> A total of 92 patients with CRSsNP took part in the study, where they were divided randomly into 2 groups. In group I, the patients received fluticasone propionate 800 mcg/day intranasally for 12 weeks. Patients in group II were treated with prednisone at a dose of 0.5 mg/kg/day, given orally, for 7 consecutive days and continued by another week with decreasing dosage. Both groups were evaluated prior to and following treatment using the TSS score of CRS clinical symptoms, the endoscopic Lund-Kennedy scale and the Lund-Mackay CT staging of chronic rhinosinusitis. Statistical analy-sis of the effectiveness of treatment was carried out in subgroups according to the total IgE serum concentrations obtained before treatment. </br></br> <b>Results:</b> Both groups of patients achieved statistically significant improvement in the TSS evaluation, as well as in endosco-pic and CT imaging findings. In patients with a total IgE serum concentration over 100 IU/ml systemic steroid therapy sho-wed significantly greater effect on the relief of CRS symptoms in the TSS score than intranasal steroid therapy. Analogous differences in the effectiveness of both methods were not found in patients with a normal total IgE serum concentration (<100 IU/ml). </br></br> <b>Conclusions:</b> A short course of systemic steroid therapy is more effective than local treatment in relieving of CRS symptoms in patients with CRSsNP with elevated serum concentration of IgE antibodies. Atopy may be considered a specific predictor of response to steroid therapy in the treatment of chronic rhinosinusitis.

Short Term Pre-Operative Oral Corticosteroids-Tissue Remodeling in Chronic Rhinosinusitis with Nasal Polyps

Chronic rhinosinusitis is a process involving a number of adverse changes in the mucosa of the paranasal sinuses and nasal polyps. The main histological features of tissue remodeling are changes in epithelial structure, oedema, degradation of ECM (extracellular matrix), angiogenesis, and subepithelial fibrosis. In this study, patients were divided into two groups: group 1—patients with CRSwNP (chronic rhinosinusitis with nasal polyps) taking a nasal steroid and an oral steroid in the preoperative period, and group 2—patients with CRSwNP taking only the nasal steroid in the preoperative period. All samples were subject to histopatologic evaluation. The aim of this study was to investigate the effect of oral corticosteroids and topical steroids on the tissue of paranasal sinuses. We have shown statistically significant decreases in tissue eosinophilia per 5HPF and decreased fibrosis in group 1. No significant differences were presented in the percentage of total tissue oedema, epithelium, neutrophils, basement membrane thickening and vessels. Using systemic administration of 40 mg of prednisone for seven days decreased the counts of eosinophils and decreased fibrosis in the nasal polyps tissue in CRSwNP.

Alteration of Histopathology in Recurrent Nasal Polyps

OBJECTIVE

The objective of this study was to analyze the histopathologic changes in recurrent nasal polyps (NPs) in terms of tissue inflammatory cells infiltration and mucosal remodeling.

METHODS

Thirty-five patients with primary NPs requiring a revision surgery during follow-up and a matched control group of 35 primary NP patients without recurrence were retrospectively enrolled. Histopathologic examination was performed of tissue inflammatory cells, subepithelial edema, epithelial cell hyperplasia, basement membrane thickness, and fibrosis.

RESULTS

The mean eosinophil and neutrophil counts, proportions of eosinophil and neutrophil, as well as total inflammatory cell count were significantly higher in the recurrent group than those in the controls. Higher subepithelial edema was seen in the recurrent group. Within the recurrent group, the mean tissue eosinophil count and relative eosinophilia reduced from the first operation to revision surgery, whereas neutrophil count and proportion, and total inflammatory cell counts remained unchanged. Subepithelial edema and epithelial cell hyperplasia were significantly reduced after the first surgical procedure.

CONCLUSION

NP recurrence is associated with higher inflammatory grade (especially in eosinophilia and neutrophilia). Surgical and corticoid treatments may have an impact on mucosal histopathologic changes but need further certification.

Matrix metalloproteinases and chronic rhinosinusitis with nasal polyposis. Unravelling a puzzle through a systematic review

BACKGROUND

The expression of metalloproteinases (MMPs) in chronic rhinosinusitis with nasal polyposis (CRSwNP) was reviewed in order to investigate their possible use as therapeutical targets and/or biomarkers.

METHODOLOGY

The differences between CRSwNP and normal controls or CRS without NP, as well as the effects of various treatments on MMPs, tissue inhibitors of MMPs (TIMPs) and MMP/TIMP ratios were considered as primary outcomes. Additional factors reported to affect MMP expression levels were noted as secondary outcomes. Data regarding inflammatory subtypes, patients’ clinical characteristics, controls, laboratory method(s) and origin of samples were also pooled. Studies on 10 or fewer patients or on specimens other than nasal and serum were excluded.

RESULTS

Forty-three studies were included. Tissue sample origin, allergic rhinitis, smoking, infection, medication intake and primary or recurrent disease should be considered as confounding factors for MMP levels. MMP-1 and -7 were consistently found to be significantly higher in CRSwNP patients than controls. CRSwNP endotypes with distinctly different inflammation patterns seem to present similar MMP-related remodelling patterns.

CONCLUSIONS

The existing literature has revealed several population and methodology related confounding factors and remains inconclusive regarding the roles of MMPs in CRSwNP pathophysiology and their possible clinical usefulness as biomarkers and therapeutical targets.

Epithelial barriers in allergy and asthma

The respiratory epithelium provides a physical, functional, and immunologic barrier to protect the host from the potential harming effects of inhaled environmental particles and to guarantee maintenance of a healthy state of the host. When compromised, activation of immune/inflammatory responses against exogenous allergens, microbial substances, and pollutants might occur, rendering individuals prone to develop chronic inflammation as seen in allergic rhinitis, chronic rhinosinusitis, and asthma. The airway epithelium in asthma and upper airway diseases is dysfunctional due to disturbed tight junction formation. By putting the epithelial barrier to the forefront of the pathophysiology of airway inflammation, different approaches to diagnose and target epithelial barrier defects are currently being developed. Using single-cell transcriptomics, novel epithelial cell types are being unraveled that might play a role in chronicity of respiratory diseases. We here review and discuss the current understandings of epithelial barrier defects in type 2-driven chronic inflammation of the upper and lower airways, the estimated contribution of these novel identified epithelial cells to disease, and the current clinical challenges in relation to diagnosis and treatment of allergic rhinitis, chronic rhinosinusitis, and asthma.

Advances in the Knowledge of the Underlying Airway Remodeling Mechanisms in Chronic Rhinosinusitis Based on the Endotypes: A Review

Chronic rhinosinusitis (CRS) is a chronic inflammatory condition of the nasal and paranasal sinus mucosa that affects up to 10% of the population worldwide. CRS is the most representative disease of the upper respiratory tract where airway remodeling occurs, including epithelial damage, thickening of the basement membrane, fibrosis, goblet cell hyperplasia, subepithelial edema, and osteitis. CRS is divided into two phenotypes according to the presence or absence of nasal polyps: CRS with nasal polyp (CRSwNP) and CRS without nasal polyps (CRSsNP). Based on the underlying pathophysiologic mechanism, CRS is also classified as eosinophilic CRS and non-eosinophilic CRS, owing to Type 2 T helper (Th2)-based inflammation and Type 1 T helper (Th1)/Type 17 T helper (Th17) skewed immune response, respectively. Differences in tissue remodeling in CRS are suggested to be based on the clinical phenotype and endotypes; this is because fibrosis is prominent in CRSsNP, whereas edematous changes occur in CRSwNP, especially in the eosinophilic type. This review aims to summarize the latest information on the different mechanisms of airway remodeling in CRS according to distinct endotypes.

Reduced Expression of Antimicrobial Protein Secretory Leukoprotease Inhibitor and Clusterin in Chronic Rhinosinusitis with Nasal Polyps

Introduction

Antimicrobial peptides and proteins (AMPs) constitute the first line of defense against pathogenic microorganisms in the airway. The association between AMPs and chronic rhinosinusitis with nasal polyps (CRSwNP) requires further investigations. This study is aimed at investigating the expression and regulation of major dysregulated AMPs in the nasal mucosa of CRSwNP.

Methods

The expression of AMPs was analyzed in nasal tissue from patients with eosinophilic (E) CRSwNP and nonECRSwNP and healthy subjects using RNA sequencing. The 10 most abundant AMPs expressed differentially in CRSwNP patients were verified by real-time PCR, and of these, the expression and regulation of secretory leukoprotease inhibitor (SLPI) and clusterin (CLU) were investigated further.

Results

The 10 most abundant AMPs expressed differentially in CRSwNP compared to healthy control, regardless of subtypes, included BPIFA1, BPIFB1, BPIFB2, CLU, LTF, LYZ, and SLPI, which were downregulated, and S100A8, S100A9, and HIST1H2BC, which were upregulated. ELISA and immunofluorescence confirmed the decreased expression of SLPI and CLU levels in CRSwNP. SLPI is expressed in both nasal epithelial cells and glandular cells, whereas CLU is mainly expressed in glandular cells. AB/PAS staining further demonstrated that both SLPI and CLU were mainly produced by mucous cells in submucosal glands. Furthermore, the numbers of submucosal glands were significantly decreased in nasal polyp tissue of CRSwNP compared to nasal tissue of controls. SLPI was downregulated by TGF-β1 and IL-4 in cultured nasal tissues in vitro, while CLU expression was inhibited by TGF-β1. Glucocorticoid treatment for 2 weeks significantly increased the expression of all downregulated AMPs, but not LYZ. Additionally, budesonide significantly increased the expression of SLPI and CLU in cultured nasal tissues.

Conclusion

The expression of major antimicrobial proteins is significantly decreased in nasal tissue of CRSwNP. The expression of SLPI and CLU is correlated with the numbers of submucosal glands and regulated by inflammatory cytokines and glucocorticoids.

Oral Corticosteroid Regimens in the Management of Chronic Rhinosinusitis

BACKGROUND

Oral corticosteroids are often used in the medical management of chronic rhinosinusitis (CRS) with and without polyps. The purpose of our study is to review the literature for studies reporting the dosage of oral corticosteroids as part of the appropriate medical management prior to, immediately before, and after surgical intervention.

METHODS

We reviewed the literature for oral corticosteroid regimens given to patients with CRS from March 2012 to September 2018. Studies that did not disclose the exact doses of the regimen were excluded from our analysis.

RESULTS

Our search resulted in 7 articles with 4 studies of Level of Evidence (LOE) 1b, 2 studies with LOE III, and 1 study with LOE IV. The daily doses varied from 15 mg to 1 mg/kg, and with total doses ranging from 150 to 352 mg. In addition, several studies gave the same regimen to both subtypes of CRS. There was no mention of side effects in most of the studies.

CONCLUSION

There is a wide variation in the steroid doses given to patients with CRS and prospective or randomized controlled trials are needed to provide better improved evidence.

Histopathologic Influences of Comorbid Smoking Status in Chronic Rhinosinusitis

Background

Smoking status has been established as a known irritant of the upper and lower respiratory tracts, leading to inflammation throughout the respiratory system. Tobacco smoking is one comorbidity encountered among chronic rhinosinusitis (CRS) patients. The histopathologic features of CRS and comorbid smoking status have yet to be determined by structured histopathology and may have important implications on disease management.

Methods

Retrospective study of structured histopathology reports analyzing sinus tissue removed during functional endoscopic sinus surgery. Histopathology variables were compared among patients with CRS who were reported as never smokers, former smokers, or current smokers.

Results

A total of 285 CRS patients were included: 173 never smokers, 85 former smokers, and 27 current smokers. When compared with former smokers, current smokers demonstrated increased basement membrane thickening (88.9% vs 67.1%, P <.020). Compared with never smokers, former and current smokers collectively demonstrated increased hyperplastic changes (14.3% vs 6.9%, P < .035), increased squamous metaplasia (26.8% vs 17.3%, P < .040), and trends toward increased basement membrane thickening (72.3% vs 65.3%, P < .124) and increased fibrosis (47.3% vs 40.5%, P < .154).

Conclusion

Smoking status may influence histopathologic tissue-level changes in CRS disease. Interestingly, former and current smokers maintained few differences in histopathology. However, former and current smokers collectively demonstrated increased chronic inflammatory changes compared with never smokers. These findings suggest that the timing of smoking exposure has limited effect on the tissue level, rather exposure overall influences inflammatory change. These findings may have important implications on medical and surgical management of CRS disease and comorbid smoking status.

Key role of the epithelium in chronic upper airways diseases

The respiratory epithelium of the upper airways is a first-line defence against inhaled irritants, pathogens and allergens. It ensures a physical barrier provided by apical junctions and mucociliary clearance to avoid excessive activation of the immune system. The epithelium also forms a chemical and immunological barrier, extensively equipped to protect the airways against external aggressions before the adaptive immune system is required. Under normal circumstances, the epithelium is capable of recovering rapidly after damage. This manuscript reviews these main properties of the upper airway epithelium as well as its reported impairments in chronic inflammatory diseases. The knowledge on normal epithelial functions and their dysregulation in upper airway diseases should help to design new epithelial-targeted treatments.

Whole-transcriptome sequencing reveals heightened inflammation and defective host defence responses in chronic rhinosinusitis with nasal polyps

INTRODUCTION

The pathways underlying chronic rhinosinusitis with nasal polyps (CRSwNP) are unclear. We conducted genome-wide gene expression analysis to determine pathways and candidate gene sets associated with CRSwNP.

METHODS

We performed whole-transcriptome RNA sequencing on 42 polyp (CRSwNP-NP) and 33 paired nonpolyp inferior turbinate (CRSwNP-IT) tissues from patients with CRSwNP and 28 inferior turbinate samples from non-CRS controls (CS-IT). We analysed the differentially expressed genes (DEGs) and the gene sets that were enriched in functional pathways.

RESULTS

Principal component-informed analysis revealed cilium function and immune regulation as the two main Gene Ontology (GO) categories differentiating CRSwNP patients from controls. We detected 6182 and 1592 DEGs between CRSwNP-NP versus CS-IT and between CRSwNP-NP versus CRSwNP-IT tissues, respectively. Atopy status did not have a major impact on gene expression in various tissues. GO analysis on these DEGs implicated extracellular matrix (ECM) disassembly, O-glycan processing, angiogenesis and host viral response in CRSwNP pathogenesis. Ingenuity Pathway Analysis identified significant enrichment of type 1 interferon signalling and axonal guidance canonical pathways, angiogenesis, and collagen and fibrotic changes in CRSwNP (CRSwNP-NP and CRSwNP-IT) tissues compared with CS-IT. Finally, gene set enrichment analysis implicated sets of genes co-regulated in processes associated with inflammatory response and aberrant cell differentiation in polyp formation.

CONCLUSIONS

Gene signatures involved in defective host defences (including cilia dysfunction and immune dysregulation), inflammation and abnormal metabolism of ECM are implicated in CRSwNP. Functional validation of these gene expression patterns will open opportunities for CRSwNP therapeutic interventions such as biologics and immunomodulators.

Synergy of Interleukin (IL)-5 and IL-18 in eosinophil mediated pathogenesis of allergic diseases

Eosinophils are circulating granulocytes that have pleiotropic effects in response to inflammatory signals in the body. In response to allergens or pathogens, exposure eosinophils are recruited in various organs that execute pathological immune responses. IL-5 plays a key role in the differentiation, development, and survival of eosinophils. Eosinophils are involved in a variety of allergic diseases including asthma, dermatitis and various gastrointestinal disorders (EGID). IL-5 signal transduction involves JAK-STAT-p38MAPK-NFκB activation and executes extracellular matrix remodeling, EMT transition and immune responses in allergic diseases. IL-18 is a classical cytokine also involved in immune responses and has a critical role in inflammasome pathway. We recently identified the IL-18 role in the generation, transformation, and maturation of (CD101+CD274+) pathogenic eosinophils. In, addition, several other cytokines like IL-2, IL-4, IL-13, IL-21, and IL-33 also contribute in advancing eosinophils associated immune responses in innate and adaptive immunity. This review discusses with a major focus (1) Eosinophils and its constituents, (2) Role of IL-5 and IL-18 in eosinophils development, transformation, maturation, signal transduction of IL-5 and IL-18, (3) The role of eosinophils in allergic disorders and (4) The role of several other associated cytokines in promoting eosinophils mediated allergic diseases.

Comparison of Corticosteroids by 3 Approaches to the Treatment of Chronic Rhinosinusitis With Nasal Polyps

Purpose

Corticosteroids are regarded as the mainstay of medical treatment of eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP). To date, a head-to-head comparison of the efficacy and safety of glucocorticoid preparations administered via different routes for the treatment of chronic rhinosinusitis with nasal polyps has not been reported. To compare the efficacy and safety of steroids administered via the oral, intranasal spray and transnasal nebulization routes in the management of ECRSwNP over a short course.

Methods

Overall, 91 patients with ECRSwNP were recruited prospectively and randomized to receive either oral methylprednisolone, budesonide inhalation suspension (BIS) via transnasal nebulization, or budesonide nasal spray (BNS) for 2 weeks. Nasal symptoms and polyp sizes were assessed before and after the treatment. Similarly, nasal polyp samples were evaluated for immunological and tissue remodeling markers. Serum cortisol levels were assessed as a safety outcome.

Results

Oral methylprednisolone and BIS decreased symptoms and polyp sizes to a significantly greater extent from baseline (P < 0.05) than BNS. Similarly, BIS and oral methylprednisolone significantly reduced eosinophils, T helper 2 cells, eosinophil cationic protein, interleukin (IL)-5, and expression of matrix metalloproteinases 2 and 9, and significantly increased type 1 regulatory T cells, IL-10, transforming growth factor-β, and tissue inhibitor of metalloproteinases 1 and 2 in nasal polyps to a greater extent than BNS. Post-treatment serum cortisol levels were significantly decreased by oral methylprednisolone compared to BIS or BNS, which did not significantly alter the cortisol levels.

Conclusions

A short course of BIS transnasal nebulization is more efficacious compared to BNS in the management of ECRSwNP and is safer than oral methylprednisolone with respect to hypothalamic-pituitary-adrenal axis function.

How to Assess, Control, and Manage Uncontrolled CRS/Nasal Polyp Patients

PURPOSE OF REVIEW

Chronic rhinosinusitis (CRS) is a multidimensional inflammatory disorder of the nose and paranasal sinuses. We reviewed the recent literature to identify improved methods to assess, control, and manage these difficult to control patients.

RECENT FINDINGS

The role of endotyping in CRS has offered a better understanding of the underlying pathophysiology and allows for more targeted treatment. The understanding of systemic disorders and their role in CRS and the importance of topical treatment reaching the sinuses has also allowed for better control of these patients. We have provided some of the commonly identified causes for uncontrolled CRS and a sensible approach to assessing these patients. We have also focused on common areas of pitfalls in the surgery and choice of patients and the role for ongoing systemic treatment. The future of managing this difficult condition includes endotyping using inflammatory markers and individualizing the treatment to the patient by using specific monoclonal antibodies.

IL-25-induced activation of nasal fibroblast and its association with the remodeling of chronic rhinosinusitis with nasal polyposis

Background and objective

Interleukin (IL)-25 has been shown to play an important role in the pathogenesis of chronic rhinosinusitis with nasal polyps. Nasal polyps are associated with chronic inflammation of the mucous membranes in the paranasal sinuses and are involved in extracellular matrix (ECM) accumulation. The aim of this study is to evaluate the effects of IL-25 on myofibroblast differentiation, ECM production and the expression of matrix metalloproteinases in nasal polyp derived fibroblasts (NPDFs) and to determine the molecular mechanism underlying these processes.

Materials and methods

A total of 40 patients were enrolled in this study for Immunofluorescence studies. Expression of IL17 receptor B was evaluated by real time reverse transcription polymerase chain reaction (PCR) in NPDFs. NPDFs were stimulated with IL-25 for 48 h in the presence or absence of mitogen-activated protein kinase (MAPK) and NF-κB inhibitors or small interfering RNAs (siRNA). The protein levels of fibrosis active mediators were examined using western blotting. Fibroblast migration was evaluated with a scratch assay. The total collagen amount was analyzed with the Sircol collagen assay.

Results

IL-25 induced α-SMA, fibronectin, and MMP-1 and -13, which were dependent on IL-17RB. IL-25 also induced activation of NF-κB and mitogen-activated protein kinase (MAPKs). By using the specific inhibitor of ERK, p38, JNK and NF-κB (U, SB, SP and Bay), we found that IL-25-induced expressions of α-SMA, fibronectin, and MMPs was regulated by the signaling pathways of MAPKs and NF-κB. IL-25 also induces α-SMA, fibronectin, and MMPs expression through IL-17RB-dependent pathways in NPDFs. The increased migration ability induced by IL-25 was suppressed by the specific inhibitors of MAPKs and NF-κB.

Conclusion

Our data indicate that IL-25 induced myofibroblast differentiation, fibronectin production, and MMP-1 and -13 expressions through the signaling pathways of MAPKs and NF-κB. in NPDFs and increased expression of IL-25 were also involved in the pathogenesis of nasal polyposis by affecting nasal fibroblasts in chronic rhinosinusitis with nasal polyps.

Pathogenesis of eosinophilic chronic rhinosinusitis

Eosinophilic chronic rhinosinusitis (ECRS) is considered a refractory and intractable disease. Patients with ECRS present with thick mucus production, long-term nasal congestion, loss of sense of smell, and intermittent acute exacerbations secondary to bacterial infections. Despite medical and surgical interventions, there is a high rate of recurrence with significant impairment to quality of life. The recent increasing prevalence of ECRS in south Asian countries and the strong tendency of ECRS to reoccur after surgery should be considered. The majority of cases need repeat surgery, and histological examinations of these cases show eosinophilic-dominant inflammation. The degradation and accumulation of eosinophils, release of cytokines, and mucus secretion have important roles in the pathogenesis of ECRS. ECRS differs from non-ECRS, in which eosinophils are not involved in the pathogenesis of the disease, and also in terms of many clinical characteristics, blood examination and nasal polyp histological findings, clinical features of the disease after surgery, efficacy of medications, and computed tomography findings. This review describes the clinical course, diagnosis, and treatment of ECRS as well as its pathophysiology and the role of eosinophils, mucus, cytokines, and other mediators in the pathogenesis of ECRS.

Clinical implications of mucosal remodeling from chronic rhinosinusitis

BACKGROUND

Prognostic implications of mucosal remodeling in chronic rhinosinusitis (CRS) remain unclear. Remodeling of respiratory mucosa in asthma is associated with greater medication use and decreased function. This study investigates the implications of mucosal remodeling on long-term clinical outcomes in patients with CRS.

METHODS

A case-control study of adult patients with CRS undergoing endoscopic sinus surgery (ESS) was performed. Mucosal remodeling was defined by squamous metaplasia, subepithelial fibrosis, and/or basement membrane thickening. The presence of remodeling changes were assessed relative to clinical and treatment outcomes at a minimum of 12 months postoperatively. Clinical outcomes were assessed at baseline and 12 months using a Nasal Symptom Score (NSS) and 22-item Sino-Nasal Outcome Test (SNOT-22). Treatment outcomes were assessed by oral corticosteroid usage (burst/continuous), topical corticosteroid irrigation frequency, and further surgical intervention.

RESULTS

A total of 110 patients (48.73 ± 14.75 years, 48.2% female) were assessed. Significant improvements where seen for the entire population, in both NSS (2.64 ± 1.06 to 1.34 ± 1.08, p < 0.001) and SNOT-22 (2.05 ± 0.96 to 1.06 ± 0.79, p < 0.001). Patients with remodeling (n = 88) were younger (47.2 ± 14.8 vs 54.7 ± 13.5 years, p = 0.03), but had similar symptom scores. Remodeling was seen in CRS with nasal polyposis (CRSwNP) (54.5%) and eosinophilic chronic rhinosinusitis (eCRS) (59.8%). Symptom improvement at 12 months was similar between remodeled and non-remodeled groups (NSS: Δ1.34 ± 1.20 vs Δ1.12 ± 1.31, p = 0.395; SNOT-22: Δ1.05 ± 0.91 vs Δ0.73 ± 0.95, p = 0.124); however, patients with remodeling had greater corticosteroid irrigation frequency (64.0% vs 31.6% daily use, Kendall's tau-b p = 0.004).

CONCLUSION

Established mucosal remodeling predicts a greater reliance on topical therapies to reach similar clinical endpoints as those without remodeling.