Heterogeneous inflammatory patterns in chronic rhinosinusitis without nasal polyps in Chicago, Illinois

Biologics in Chronic Rhinosinusitis: Current and Emerging

Chronic rhinosinusitis (CRS) is categorized phenotypically into CRS with and without nasal polyps (CRSwNP, CRSsNP). Endotyping categorizes the disease based on immune cell activity and inflammatory mechanisms into Type 1, Type 2, and Type 3. The Type 2 endotype is the most researched and associated with asthma, atopic disease, and severe CRSwNP. For patients with poorly controlled CRSwNP, there are 3 approved biologic treatments: omalizumab, dupilumab, and mepolizumab. Many other biologics are being tested in Type 2, non-Type 2, and mixed endotypes in CRSwNP and CRSsNP. These studies will play a significant role in shaping the future of CRS management.

Consultation for Chronic Rhinosinusitis With Nasal Polyps and Asthma: Clinical Presentation, Diagnostic Workup, and Treatment Options

Chronic rhinosinusitis (CRS) is characterized by chronic inflammation of the sinonasal mucosa, affects over 12% of the US population, and costs over $20 billion annually. CRS can be divided into 2 major phenotypes based on whether nasal polyps are present (chronic rhinosinusitis with nasal polyps [CRSwNP]) or absent (chronic rhinosinusitis without nasal polyps). This grand rounds review will discuss the clinical approach to patients with CRSwNP, including typical presentations, workup, and currently available treatment options. Tools that physicians can use to assess subjective sinonasal symptoms, as well as objective measures of disease, will be reviewed. Additional focus will be on recognizing clinical comorbidities commonly associated with CRSwNP, including asthma, bronchiectasis, allergic rhinitis, and nonsteroidal anti-inflammatory drug-exacerbated respiratory disease. Clinical outcomes can be improved by providing a comprehensive approach to evaluating (and managing) patients with CRSwNP.

Role of specific immunoglobulin-E in chronic rhinosinusitis: Its clinical relevance according to nasal challenge test

Background

Guidelines for chronic rhinosinusitis (CRS) propose total IgE and eosinophils as important biomarkers to identify type-2 inflammation. Despite the fact that specific IgE (sIgE) have been identified as a clinical predictor in some type-2 diseases for different clinical outcomes, its role in CRS has yet to be explored in detail.

Objetive

To describe systemic and local sIgE in CRS and explore its possible association with clinical outcomes using nasal challenge tests (NCT).

Methods

In CRS patients, we measure total IgE, serum sIgE (SsIgE) and nasosinusal sIgE (NsIgE) against 9 allergenic sources; Der p, Der f, Blo t, Can f, Fel d, Per a, grasses, Staphylococcus enterotoxin A, and B. NCT was done using the allergen with the higher sIgE prevalence (Der p).

Results

A total of 174 patients were included. Prevalence of SsIgE was 52.8% and NsIgE 46.5%; Der p was the principal allergen for SsIgE and NsIgE. The presence of nasal polyps, asthma comorbidity, NSAID hypersensitivity, and hyposmia, were significantly associated with the presence of SsIgE and NsIgE but not with total IgE. NCT-Der p was performed in 73 CRS patients, being positive in 33 (45.2%). SsIgE have the best diagnostic accuracy (79.4%) to predict NCT results (NsIgE 67.5% total IgE 52%).

Conclusion

Specific IgE is a better biomarker in CRS than total IgE. Patients with clinically relevant SsIgE have a pheno-endotype associated with different clinical outcomes. Considering the clinical relevance of SsIgE demonstrated by NCT, interventions like allergen immunotherapy in CRS must be study.

Single cell RNA sequencing of human eosinophils from nasal polyps reveals eosinophil heterogeneity in chronic rhinosinusitis tissue

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by type 2 inflammation in the United States, but the actual roles that eosinophils play in CRSwNP remain largely unclear.

OBJECTIVE

To reveal the roles and heterogeneity of eosinophils in nasal polyp (NP) tissue, we performed single cell RNA sequencing (scRNA-Seq) analysis of NP tissue.

METHODS

Sinonasal tissues (NP and control sinus tissue) and patient matched peripheral blood (PB) samples were obtained from 5 control patients and 5 patients with CRSwNP. Eosinophils were enriched before processing for scRNA-Seq. The gene expression profiles in eosinophils were determined by microwell-based scRNA-Seq technology (BD Rhapsody platform). We predicted the overall function of NP eosinophils by Gene Ontology (geneontology.org) enrichment and pathway analyses and confirmed expression of selected genes by flow cytometry.

RESULTS

After filtering out contaminating cells, we detected 5,542 eosinophils from control PB, 3,883 eosinophils from CRSwNP PB, 101 eosinophils from control sinus tissues (not included in further analyses), and 9,727 eosinophils from NPs by scRNA-Seq. We found that 204 genes were downregulated and 354 genes upregulated in NP eosinophils compared to all PB eosinophils (>1.5-fold, Padj < .05). Upregulated genes in NP eosinophils were associated with activation, cytokine-mediated signaling, growth factor activity, NF-κB signaling, and antiapoptotic molecules. NP eosinophils displayed 4 clusters revealing potential heterogeneity of eosinophils in NP tissue.

CONCLUSIONS

Elevated eosinophils in NP tissue appear to exist in several subtypes that may play important pathogenic roles in CRSwNP, in part by controlling inflammation and hyperproliferation of other cells.

Comparison of cytokine expression and disease severity between plasma cell-dominant and eosinophil-dominant patients in chronic rhinosinusitis with nasal polyps

PURPOSE

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous disease characterized by inflammation of the nasal and sinus mucosa. The inflammatory patterns may differ among patients, leading to different subtypes based on the dominant inflammatory cell type. This study aimed to compare the differences in cytokine expression and disease severity between plasma cell-dominant and eosinophil-dominant subtypes in patients with CRSwNP.

METHODS

This study included 53 CRSwNP patients and 19 control subjects who did not have asthma or a history of cigarette smoking. The expression of cytokines and inflammatory cells was assessed via enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, respectively.

RESULTS

Among the cytokines analyzed, only IL-6 was significantly different between the two subtypes. A greater proportion of mast cells and IgE cells was present in plasma cell-dominant CRSwNP patients than in eosinophil-dominant group. For the three disease severity scores (LMK-CT, TPS and SNOT-22), objective scores (LMK-CT and TPS) were greater in the eosinophil-dominant CRSwNP group, while the opposite result was shown for the subjective score (SNOT-22). Additionally, the percentage of plasma cell-dominant cells was significantly positively correlated with disease severity according to the TPS and SNOT-22 scores.

CONCLUSIONS

Our data revealed that plasma cell-dominant inflammation, a subtype of type 2 CRS, was significantly correlated with subjective disease severity. The study also highlights the role of IL-6, IgE and mast cells as distinguishing factors between eosinophil-dominant and plasma cell-dominant CRSwNP. This information could be useful for clinical diagnosis and personalized treatment.

IL-13 and IL-13-induced periostin levels are specifically decreased in patients following endoscopic sinus surgery for chronic rhinosinusitis

BACKGROUND

Type 2 (T2) inflammation plays a pathogenic role in chronic rhinosinusitis (CRS). The effects of endoscopic sinus surgery (ESS) on T2 inflammation are unknown.

OBJECTIVE

The aim of this study was to compare T2 inflammatory biomarkers from middle meatal (MM) mucus for distinguishing patients with CRS from CRS-free patients, identifying major phenotypes (CRS without nasal polyps [CRSsNP] and CRS with nasal polyps [CRSwNP]), assessing endotypic change, and establishing cross-sectional and longitudinal outcomes in patients undergoing ESS.

METHODS

MM mucus samples were collected from patients with CRSsNP and patients with CRSwNP before and 6 to 12 months after ESS and compared with samples from CRS-free control patients. T2 biomarkers were evaluated both continuously and using threshold-based definitions of T2 endotype to identify relationships with patient-reported (based on the 22-Item Sinonasal Outcomes Test and Chronic Rhinosinusitis Patient-Reported Outcomes Measure) and clinician-reported (radiographic and endoscopic) severity. Linear mixed models were developed to analyze clinical variables associated with T2 biomarker levels.

RESULTS

A total of 154 patients with CRS (89 with CRSsNP and 65 with CRSwNP) were enrolled, with a mean interval of 9 months between ESS and follow-up. An analysis of pre-ESS MM mucus samples revealed elevated levels of T2 mediators in patients with CRSwNP versus in patients with CRSsNP and CRS-free controls. Temporally stable correlations between levels of IL-13 and IL-5, levels of periostin and complement 5a, and levels of eosinophil cationic protein (ECP) and eotaxin-3 were observed. On this basis and on the basis of pathologic significance, levels of IL-13, periostin and ECP were further analyzed. After ESS, levels of IL-13 and periostin decreased significantly, whereas ECP levels remained unchanged. Across pre- and post-ESS evaluation, the T2 endotype was associated with radiographic severity but did not predict outcomes. CRSwNP status and African American race were associated with higher levels of IL-13 and periostin, whereas ECP level was higher in patients undergoing extensive surgery.

CONCLUSION

ESS decreased levels of IL-13 and periostin in the middle meatus. T2 inflammation after ESS was correlated with patient- and clinician-reported severity across phenotypes. Pre-ESS T2 inflammation did not predict post-ESS outcomes.

Multidimensional Impact of Dupilumab on Chronic Rhinosinusitis with Nasal Polyps: A Complete Health Technology Assessment of Clinical, Economic, and Non-Clinical Domains

Chronic RhinoSinusitis with Nasal Polyps (CRSwNP) represents a condition mainly caused by the type 2 inflammation presence and marked by the existence of polyps within the nasal and paranasal sinuses. The standard of care includes intranasal steroids, additional burst of systemic steroids, if needed, and surgery. However, recurrence is common, especially among patients with comorbid type 2 inflammatory diseases. Recently, biological drugs, addressing the underlying cause of the disease, have been approved in Italy (dupilumab, omalizumab, and mepolizumab). A Health Technology Assessment was conducted to define multidimensional impact, assuming Italian NHS perspective and a 12-month time horizon. The EUnetHTA Core Model was deployed, using the following methods to analyze the domains: (i) literature evidence; (ii) administration of semi-structured questionnaires to 17 healthcare professionals; (iii) health economics tools to define the economic sustainability for the system. Evidence from NMA and ITC showed a more favorable safety profile and better efficacy for dupilumab compared with alternative biologics. All the analyses, synthesizing cost and efficacy measures, showed that dupilumab is the preferable alternative. Specifically, the cost per responder analysis for dupilumab, exhibiting a 67.0% response rate at Week 52, is notably economical at 14,209EUR per responder. This presents a more economical profile compared with the cost per responder for omalizumab (36.2% response rate) at 24,999EUR and mepolizumab (28.5% response rate) at 31,863EUR. These results underscore dupilumab's potential, not merely in terms of clinical outcomes, but also in terms of economic rationality, thereby solidifying its status as a valid and preferrable alternative in the management of CRSwNP, in the context of the Italian NHS.

Non-Type 2 and Mixed Inflammation in Chronic Rhinosinusitis and Lower Airway Disease

OBJECTIVE

The aim was to discuss the role of non-type 2 inflammation in patients diagnosed with chronic rhinosinusitis (CRS) and comorbid lower airway disease.

DATA SOURCES

Medline, Embase, National Institute for Health and Care Excellence, TRIP Database, ProQuest, Clinicaltrials.gov, Cochrane Central Registry of Controlled Trials, Web of Science, government and health organizations, and graduate-level theses.

REVIEW METHODS

This scoping review followed PRISMA-ScR guidelines. Search strategy was peer-reviewed by medical librarians. Studies were included if they utilized airway sampling, non-type 2 cytokines, and patients with CRS and lower airway disease.

RESULTS

Twenty-seven from 7060 articles were included. In patients with CRS and comorbid asthma, aspirin-exacerbated respiratory disease (AERD), and chronic obstructive pulmonary disease (COPD)/bronchiectasis, 60% (n = 12), 33% (n = 2), and 100% (n = 1), respectively, demonstrated mixed or non-type 2 endotypes. Comorbid CRS and asthma produced type 1 (n = 1.5), type 2 (n = 8), type 3 (n = 1), mixed type 1/2 (n = 1), and mixed type 1/2/3 (n = 8.5) endotype shifts. AERD demonstrated type 2 (n = 4), mixed type 2/3 (n = 1), and mixed type 1/2/3 (n = 1) endotype shifts. CRS with COPD or bronchiectasis demonstrated a mixed 1/2 (n = 1) endotype shift.

CONCLUSION

Type 2 disease has been extensively reviewed due to advent biologics targeting type 2 inflammation, but outcomes may be suboptimal due to the presence of non-type 2 inflammation. A proportion of patients with CRS and comorbid lower airway disease demonstrated mixed and non-type 2 endotype shifts. This emphasizes that patients with unified airway disease may have forms of inflammation beyond classical type 2 disease which could inform biologic development. Laryngoscope, 134:1005-1013, 2024.

Prevalence of type 2 inflammatory signatures and efficacy of dupilumab in patients with chronic rhinosinusitis with nasal polyps from two phase 3 clinical trials: SINUS-24 and SINUS-52

BACKGROUND

This post hoc analysis of the international SINUS-24/-52 trials (NCT02912468/NCT02898454) aimed to assess dupilumab efficacy in patients with severe chronic rhinosinusitis with nasal polyps (CRSwNP) according to different definitions of type 2 inflammatory signature.

METHODS

Six definitions of type 2 inflammation were used: ≥150 eosinophils/μL or total immunoglobulin E (IgE) ≥100 IU/mL with a coexisting type 2 condition; ≥150 eosinophils/μL or total IgE ≥100 IU/mL; ≥150 eosinophils/μL; ≥250 eosinophils/μL or total IgE ≥100 IU/mL; coexisting asthma or ≥300 eosinophils/μL; presence of a coexisting type 2 condition. Odds ratios (ORs; dupilumab vs. placebo) for achieving clinically meaningful improvement (≥1 point) from baseline to week 24 (pooled SINUS-24/-52) and week 52 (SINUS-52) were calculated for nasal polyp score (NPS; range 0-8), nasal congestion/obstruction score (NC; 0-3), and loss of smell score (LoS; 0-3).

RESULTS

At baseline (n = 724), most patients displayed a type 2 inflammatory signature across definitions (64.2%-95.3%). At week 24, ORs for clinically meaningful improvement ranged from 11.9 to 14.9 for NPS across type 2 definitions, 6.5-9.6 for NC, and 12.2-17.8 for LoS (all p < 0.0001). OR ranges were similar or greater at week 52: 19.0-36.6, 7.6-12.1, and 9.2-33.5, respectively (all p < 0.0001).

CONCLUSION

Most patients with CRSwNP in the SINUS study had type 2 inflammation. Dupilumab demonstrated robust efficacy across definitions of type 2 inflammation, consistent with its profile as an inhibitor of Interleukin-4 and Interleukin-13 signaling, key and central drivers of type 2 inflammation in CRSwNP.

KEY POINTS

This study assessed type 2 inflammation prevalence and dupilumab efficacy in chronic rhinosinusitis with nasal polyps according to algorithm-defined type 2 inflammation Dupilumab efficacy was similar across all type 2 definitions.

The last step to achieve barrier damage control

Heterogeneity characterises inflammatory diseases and different phenotypes and endotypes have been identified. Both innate and adaptive immunity contribute to the immunopathological mechanism of these diseases and barrier damage plays a prominent role triggering type 2 inflammation through the alarmins system, such as anti-Thymic Stromal Lymphopoietin (TSLP). Treatment with anti-TSLP monoclonal antibodies showed efficacy in severe asthma and clinical trials for other eosinophilic diseases are ongoing. The aim of this perspective review is to analyse current advances and future applications of TSLP inhibition to control barrier damage.

Lymphatic Vessels in Chronic Rhinosinusitis

Purpose

The purpose of this study was to analyze the nasal lymphatic system in order to uncover novel factors that might be involved in pathogenesis of chronic rhinosinusitis (CRS) with (CRSwNP) and without nasal polyps (CRSsNP).

Patients and Methods

Lymphatic vessels (LVs) and macrophages were localized and counted in the inferior and middle turbinate, the uncinate process and the ethmoid of CRSwNP and CRSsNP patients, the NP and the inferior turbinate of controls (n≥6 per group). Lysates of the same tissue types (n=7 per group) were analyzed for lymphatic vessel endothelial receptor 1 (LYVE-1), for matrix metalloproteinase 14 (MMP-14) and for Hyaluronic acid (HA) using ELISA. HA was localized in sections of CRSwNP NP, CRSsNP ethmoid and control inferior turbinate (n=6 per group). The results of HA levels were correlated to the number of macrophages in tissues. The nasal secretions of CRSwNP (n=28), CRSsNP (n=30), and control (n=30) patients were analyzed for LYVE-1 and HA using ELISA.

Results

The number of LVs was significantly lower in tissues of both CRS groups compared to the control. In the tissue lysates, LYVE-1 expression differed significantly between the CRSwNP tissues with a particularly high level in the NP. MMP-14 was significantly overexpressed in CRSwNP uncinate process. There were no significant differences in tissue HA expression. In the mucus LYVE-1 was significantly underexpressed in CRSsNP compared to CRSwNP and control, while HA was significantly underexpressed in both CRS groups. In the NP, HA and macrophages were accumulated particularly below the epithelium. Tissue levels of HA revealed a significant positive correlation with the number of macrophages.

Conclusion

CRS might be associated with an insufficient clearing of the nasal mucosa through the lymphatics. The accumulation of HA and macrophages might promote inflammation, fluid retention, and polyp formation. These results may provide novel CRS-associated factors.

Epithelial Tight Junction Anomalies in Nasal Inverted Papilloma

OBJECTIVES

As a critical component of the epithelial barrier, tight junctions (TJs) are essential in nasal mucosa against pathogen invasion. However, the function of TJs has rarely been reported in nasal inverted papilloma (NIP). This study aims to investigate the potential factors of TJs' abnormality in NIP.

METHODS

We assessed the expression of ZO-1, occludin, claudin-1, claudin-3, and claudin-7 in healthy controls and NIP by real-time quantitative polymerase chain reaction and immunofluorescent staining. The correlation between TJs expression and neutrophil count, TH 1/TH 2/TH 17 and regulatory T cell biomarkers, and the proportion of nasal epithelial cells was investigated.

RESULTS

Upregulation of ZO-1, occludin, claudin-1, and claudin-7, along with downregulation of claudin-3, was found in NIP compared to control (all p < 0.05). An abnormal proportion with a lower number of ciliated cells (control vs. NIP: 37.60 vs. 8.67) and goblet cells (12.52 vs. 0.33) together with a higher number of basal cells (45.58 vs. 124.00) in NIP. Meanwhile, claudin-3 was positively correlated with ciliated and goblet cells (all p < 0.01). Additionally, neutrophils were excessively infiltrated in NIP, negatively correlated with ZO-1, but positively with claudin-3 (all p < 0.05). Furthermore, FOXP3, IL-10, TGF-β1, IL-5, IL-13, and IL-22 levels were induced in NIP (all p < 0.01). Occludin level was negatively correlated with IL-10, IL-5, IL-13, and IL-22, whereas ZO-1 was positively with TGF-β1 (all p < 0.05).

CONCLUSION

Nasal epithelial barrier dysfunction with TJs anomalies is commonly associated with abnormal proliferation and differentiation of epithelial cells and imbalance of immune and inflammatory patterns in NIP.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:552-561, 2024.

Interaction of eosinophilic and neutrophilic inflammation in patients with chronic rhinosinusitis

PURPOSE OF REVIEW

In the past year, the endotype of chronic rhinosinusitis (CRS) has been studied from a new perspective. Eosinophilic and neutrophilic inflammation are not independent processes in the pathogenesis of CRS. In this review, we will focus on recent research on mixed eosinophilic-neutrophilic inflammation in CRS and discuss the mechanism and potential treatments.

RECENT FINDINGS

Traditionally, patients with eosinophilic CRS (ECRS) present with severe clinical manifestations, comorbidities, and a higher recurrence rate. Recent studies have found that approximately 40% of patients with ECRS present with neutrophilic infiltration, while patients with predominantly eosinophilic infiltration along with neutrophilic inflammation present with more complex inflammation, clinical manifestations and exhibit refractory characteristics.

SUMMARY

The complex inflammatory profile and refractory clinical characteristics of mixed eosinophilic-neutrophilic inflammation in CRS are current challenges for clinicians. We summarize the features of eosinophilic and neutrophilic inflammation and current studies on the mechanisms of mixed eosinophilic-neutrophilic inflammation and suggest potentially effective therapeutic methods. We hope that this review will help with determining precise treatment options for patients.

Endotypic heterogeneity and pathogenesis in chronic rhinosinusitis

PURPOSE OF REVIEW

This review aims to provide updates in realms of endotypic heterogeneity, pathogenesis at the molecular level, potential of biomarkers, and cutting-edge scope of biologics in CRS.

RECENT FINDINGS

High-dimensional analyses, such as transcriptomes, and machine learning, have significantly enhanced CRS endotyping, uncovering diverse pathogenetic mechanisms contributing to its heterogeneity. The dynamic process of epithelial remodeling in CRS pathogenesis has gained more clarity and support as exemplified by IL-13 and oncostatin M (OSM) that are shown intricately linked to epithelial barrier dysfunction. Moreover, anti-dsDNA autoantibody, BAFF, periostin, and cystatin SN show promise as potentials biomarkers, offering diagnostic and prognostic value for CRS.

SUMMARY

The identification of inflammatory molecules involved in endotype specific signaling pathways provides insights into the underlying mechanisms and verifiable biomarkers for diagnosis and prediction of disease severity. More comprehensive clinical studies should be conducted to facilitate biologics from bench to bedside in treating CRS.

Local cytokine levels associate with SNOT-22 and UPSIT scores in chronic rhinosinusitis

KEY POINTS

Elevated IL-5, IL-13, IL-33, and CCL2 correlate with lower UPSIT scores in CRS and AERD patients. Elevated IL-5, IL-13, TNF-α, CCL2, and CXCL-8 correlate with higher SNOT-22 scores in CRS and AERD patients.

Clinical Utility of Machine Learning Methods Using Regression Models for Diagnosing Eosinophilic Chronic Rhinosinusitis

Objective

Machine learning methods using regression models can predict actual values of histological eosinophil count from blood eosinophil levels. Therefore, these methods might be useful for diagnosing eosinophilic chronic rhinosinusitis, but their utility still remains unclear. We compared 2 statistical approaches, and investigated the utility of machine learning methods for diagnosing eosinophilic chronic rhinosinusitis.

Study Design

Retrospective study.

Setting

Medical center.

Methods

Data, including eosinophilic levels, obtained from blood and sinonasal samples of 264 patients with chronic rhinosinusitis (257 with and 57 without nasal polyps) were analyzed. We determined factors affecting histopathological eosinophil count in regression models. We also investigated optimal cutoff values for blood eosinophil percentages/absolute eosinophil counts (AECs) through receiver operating characteristic curves and machine-learning methods based on regression models. A histopathological eosinophil count ≥10/high-power field was defined as eosinophilic chronic rhinosinusitis.

Results

Blood eosinophil levels, nasal polyp presence, and comorbid asthma were factors affecting histopathological eosinophil count. Cutoffs between the 2 statistical approaches differed in the group with nasal polyps, but not in one without nasal polyps. Machine-learning methods identified blood eosinophil percentages ≥1% or AEC ≥100/μL as cut-offs for eosinophilic chronic rhinosinusitis with nasal polyps, while ≥6% or ≥400/μL for one without nasal polyps.

Conclusion

Cut-offs of blood eosinophil levels obtained by machine-learning methods might be useful when suspecting eosinophilic chronic rhinosinusitis prior to biopsy because of their ability to adjust covariates, dealing with overfitting, and predicting actual values of histological eosinophil count.

[Features of inflammatory endotypes and phenotypes in chronic rhinosinusitis]

Recently, significant progress has been made in identifying the cellular and molecular mechanisms responsible for the pathogenesis of chronic rhinosinusitis (CRS). Cohort studies of CRS have led to advances in the clinical understanding of this disease. New therapeutic agents have been approved or are undergoing clinical trials to expand treatment options for this disease. One of the promising areas in medicine is the provision of personalized clinical care. From this perspective, CRS can be divided into three different endotypes depending on the type of underlying inflammatory response. In the United States, CRS with and without nasal polyps is predominantly characterized as the second inflammatory endotype. CRS with nasal polyps (about 17%) and without nasal polyps (up to 20%) belongs to the 1st and 3rd inflammatory endotypes, respectively. And if for the second inflammatory endotype the effectiveness of targeted biological therapy is beyond doubt, then for the first and third inflammatory endotypes the principles of such conservative therapy are under active development. Moreover, large validated studies to confirm associations between CRS phenotypes and endotypes, as well as to find effective biological markers of inflammatory endotypes, remain to be performed.

Predictive Value of Eosinophil Cationic Protein in Nasal Secretions in Eosinophilic Chronic Rhinosinusitis

OBJECTIVES

To investigate the value of secretions Eosinophilic cationic protein (ECP) detection in the diagnosis of endotypes of Chronic rhinosinusitis (CRS) and its correlation with clinical symptoms, so as to provide guidance for the clinical application of EOS and ECP detection in secretions.

METHODS

Patients' nasal secretions and polyps (or middle turbinate for control) were collected and their EOS% and ECP levels were measured. Correlation analysis was performed for EOS% and ECP levels in secretions and tissues, respectively. The correlation between secretions EOS% and ECP and clinical symptom scores (symptomatic visual analog scale (VAS) scores, Lanza-kennedy scores from nasal endoscopy and Lund-Mackay scores from sinus CT) was further analyzed. Receiver operating characteristic curves were used to assess the predictive potential of EOS% and ECP in nasal secretions.

RESULTS

Eosinophilic chronic rhinosinusitis (ECRS) patients had higher concentrations of ECP in nasal secretions than healthy subjects and NECRS (non-eosinophilic CRS) (p < 0.0001;0.0001); EOS% in nasal secretions was higher in ECRS than healthy subjects (p = 0.0055), but the differences between ECRS and NECRS were not statistically significant (p = 0.0999). Correlation analysis showed that tissue EOS% was correlated with ECP concentration and EOS% in nasal secretions (R = 0.5943;0.2815). There was a correlation between EOS% in secretions with a total LM score (R = 0.3131); ECP concentration in secretions with a total LK score (R = 0.3792). To diagnose ECRS, the highest area under the curve (0.8230) was determined for ECP in secretions; the highest area under the curve (0.6635) was determined for EOS% in secretions.

CONCLUSION

Measurement of ECP in nasal secretions is useful for non-invasive diagnosis of ECRS.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3304-3312, 2023.

Epithelial innate immune response to Pseudomonas aeruginosa-derived flagellin in chronic rhinosinusitis

BACKGROUND

Pseudomonas aeruginosa is a common colonizing pathogen in the upper respiratory tract and is associated with recalcitrant chronic rhinosinusitis (CRS). Herein we sought to characterize the effect of P. aeruginosa-derived flagellin on human sinonasal epithelial cell (HSNEC) immune responses and determine whether these pathways are disrupted in CRS.

METHODS

Air-liquid interface cultures were established from CRS and healthy control donors. Cells were incubated with P. aeruginosa-derived flagellin for 24 hours and transcriptional changes were assessed using whole transcriptome RNA sequencing. Apical and basolateral secretion of the pro-inflammatory cytokines in interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6 were measured after stimulation by lipopolysaccharide or flagellin and responses were compared between CRS and healthy control patients.

RESULTS

HSNECs were weakly responsive to lipopolysaccharide, whereas flagellin stimulated a profound innate immune response dominated by TNF-α, IL-1β, and IL-17 signaling and activation of the IL-17C/IL-23 axis. CRS-derived HNSECs showed an altered innate immune response to flagellin, characterized by a profound increase in TNF-α secretion coupled with reduced IL-6 secretion.

CONCLUSIONS

Flagellin activates a potent innate immune response in HSNECs characterized by pro-inflammatory mediators and cytokines/chemokines associated with neutrophilic inflammation. HSNECs from CRS patients have a dysregulated innate immune response to flagellin characterized by an imbalance between IL-6 and TNF-α secretion.

A Decade of Pathogenesis Advances in Non-Type 2 Inflammatory Endotypes in Chronic Rhinosinusitis: 2012-2022

Chronic rhinosinusitis (CRS) is a heterogeneous disease characterized by localized inflammation of the upper airways. CRS includes two main phenotypes, namely, CRS with nasal polyps and CRS without nasal polyps. The phenotype-based classification method cannot reflect the pathological mechanism. The endotype-based classification method has been paid more and more attention by researchers. It is mainly divided into type 2 and non-type 2 endotypes. The mechanism driving the pathogenesis of non-type 2 inflammation is currently unknown. In this review, the PubMed and Web of Science databases were searched to conduct a critical analysis of representative literature works on the pathogenesis of non-type 2 inflammation in CRS published in the past decade. This review summarizes the latest evidence that may lead to the pathogenesis of non-type 2 inflammation. It is the main method that analyzing the pathogenesis from the perspective of immunology. Genomics and proteomics technique provide new approaches to the study of the pathogenesis. Due to differences in race, environment, geography, and living habits, there are differences in the occurrence of non-type 2 inflammation, which increase the difficulty of understanding the pathogenesis of non-type 2 inflammation in CRS. Studies have confirmed that non-type 2 endotype is more common in Asian patients. The emergence of overlap and unclassified endotypes has promoted the study of heterogeneity in CRS. In addition, as the source of inflammatory cells and the initiation site of the inflammatory response, microvessels and microlymphatic vessels in the nasal mucosal subepithelial tissue participate in the inflammatory response and tissue remodeling. It is uncertain whether CRS patients affect the risk of infection with SARS-CoV-2. In addition, the pathophysiological mechanism of non-type 2 CRS combined with COVID-19 remains to be further studied, and it is worth considering how to select the befitting biologics for CRS patients with non-type 2 inflammation.

Staphylococcus aureus biofilm properties and chronic rhinosinusitis severity scores correlate positively with total CD4+ T-cell frequencies and inversely with its Th1, Th17 and regulatory cell frequencies

Chronic rhinosinusitis (CRS) represents chronic inflammation of the sinus mucosa characterised by dysfunction of the sinuses' natural defence mechanisms and induction of different inflammatory pathways ranging from a Th1 to a Th2 predominant polarisation. Recalcitrant CRS is associated with Staphylococcus aureus dominant mucosal biofilms; however, S. aureus colonisation of the sinonasal mucosa has also been observed in healthy individuals challenging the significance of S. aureus in CRS pathogenesis. We aimed to investigate the relationship between CRS key inflammatory markers, S. aureus biofilm properties/virulence genes and the severity of the disease. Tissue samples were collected during endoscopic sinus surgery from the ethmoid sinuses of CRS patients with (CRSwNP) and without (CRSsNP) nasal polyps and controls (n = 59). CD3+ T-cell subset frequencies and key inflammatory markers of CD4+ helper T cells were determined using FACS analysis. Sinonasal S. aureus clinical isolates were isolated (n = 26), sequenced and grown into biofilm in vitro, followed by determining their properties, including metabolic activity, biomass, colony-forming units and exoprotein production. Disease severity was assessed using Lund-Mackay radiologic scores, Lund-Kennedy endoscopic scores and SNOT22 quality of life scores. Our results showed that S. aureus biofilm properties and CRS severity scores correlated positively with total CD4+ T-cell frequencies but looking into CD4+ T-cell subsets showed an inverse correlation with Th1 and Th17 cell frequencies. CD4+ T-cell frequencies were higher in patients harbouring lukF.PV-positive S. aureus while its regulatory and Th17 cell subset frequencies were lower in patients carrying sea- and sarT/U-positive S. aureus. Recalcitrant CRS is characterised by increased S. aureus biofilm properties in relation to increased total CD4+ helper T-cell frequencies and reduced frequencies of its Th1, Th17 and regulatory T-cell subsets. These findings offer insights into the pathophysiology of CRS and could lead to the development of more targeted therapies.

Targeting Epithelium Dysfunction and Impaired Nasal Biofilms to Treat Immunological, Functional, and Structural Abnormalities of Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) with (CRSwNP) or without (CRSsNP) nasal polyps is a prevalent and heterogeneous disorder existing as a spectrum of clinical conditions with complex underlying pathomechanisms. CRS comprises a broad syndrome characterized by multiple immunological features involving complex interactions between the genes, the microbiome, host- and microbiota-derived exosomes, the epithelial barrier, and environmental and micromilieu exposures. The main pathophysiological feature is an epithelial barrier disruption, accompanied by microbiome alterations and unpredictable and multifactorial immunologic overreactions. Extrinsic pathogens and irritants interact with multiple epithelial receptors, which show distinct expression patterns, activate numerous signaling pathways, and lead to diverse antipathogen responses. CRSsNP is mainly characterized by fibrosis and mild inflammation and is often associated with Th1 or Th17 immunological profiles. CRSwNP appears to be associated with moderate or severe type 2 (T2) or Th2 eosinophilic inflammation. The diagnosis is based on clinical, endoscopic, and imaging findings. Possible CRS biomarkers from the peripheral blood, nasal secretions, tissue biopsies, and nasally exhaled air are studied to subgroup different CRS endotypes. The primary goal of CRS management is to maintain clinical control by nasal douching with isotonic or hypertonic saline solutions, administration of nasal and systemic steroids, antibiotics, biologic agents, or, in persistent and more severe cases, appropriate surgical procedures.

Diagnostic value of myeloperoxidase and eosinophil cationic protein in nasal secretions for endotypes of chronic rhinosinusitis

OBJECTIVES

To explore associations between inflammatory endotypes and clinical presentations in CRS. To investigate the value of secretions myeloperoxidase (MPO) and eosinophilic cationic protein (ECP) detections in the diagnosis of endotypes of chronic rhinosinusitis (CRS), so as to provide guidance for the clinical application of MPO and ECP detection in secretions.

METHODS

We collected clinical symptom scores from patients with CRS and examined the differences between endotypes in clinical features. Patients' nasal secretions and polyps (or middle turbinate for control) were collected and their NEU number, EOS%, MPO and ECP levels were measured. Correlation analysis was performed for these biomarkers in secretions and tissues, respectively. Receiver operating characteristic curves were used to assess the predictive potential of the biomarkers mentioned above in nasal secretions.

RESULTS

Patients with Eos+Neu+ and Eos+Neu-CRS scored highest in most clinical symptom scores, while Eos-Neu+ and Eos-Neu-CRS scored lowest. Correlation analysis showed that tissues NEU number was correlated with NEU number and MPO level in nasal secretions (R = 0.4088; 0.6613); tissues EOS % was correlated with EOS% and ECP level in nasal secretions (R = 0.2344; 0.5774). To diagnose Neu+CRS, the highest area under the curve (AUC) (0.8961) was determined for MPO in secretions; the highest AUC (0.7400) was determined for NEU number in secretions. To diagnose Eos+Neu-CRS from Eos-Neu-CRS in Neu-CRS, the highest AUC (0.8801) was determined for ECP in secretions.

CONCLUSIONS

Clinical presentations are directly associated with CRS endotypes. Measurement of MPO and ECP in nasal secretions is useful for the endotypes diagnosis of CRS.

Macroarray expression analysis of cytokines and prostaglandin metabolism-related genes in chronic rhinosinusitis

Background

Chronic rhinosinusitis (CRS) can be divided into endotypes by functional or pathophysiologic findings.

Objective

The aim of this study was to analyze the expression of cytokines, prostaglandin (PG) synthases, and their receptors related to the pathogenesis of CRS, especially those contributing to nasal polyp (NP) formation.

Methods

NPs and uncinate tissue (UT) samples were collected from 90 patients who underwent endoscopic sinus surgery. They included 75 patients with CRS (including 45 with eosinophilic CRS [eCRS] and 30 with non-eCRS) and 15 patients without CRS. A total of 30 genes were selected for our original DNA array plate to analyze the levels of expression of 10 cytokines (IFN-γ, IL-4, IL-5, IL-10, IL-13, IL-17A, IL-22, IL-25, IL-33, and TSLP), 4 prostaglandin synthases (prostaglandin D2 [PGD2] synthase, prostaglandin E2 synthase, COX-1, and COX-2), and their 16 receptors. Clustering analysis was performed according to the expression results, and clinical findings of patients from each cluster were investigated.

Results

The samples could be divided into 3 clusters. Cluster 1 showed elevated levels of expression of IL4, IL5, IL13, TSLP, IL1RL1 (ST2 [an IL-33 receptor]), HPGDS, and GPR44 (CRTH2, a PGD2 receptor); cluster 2 showed elevated levels of expression of IL17A and PTGES; and cluster 3 showed an elevated level of expression of IL25. Regarding clinical features, the main characteristics of each cluster were as follows: NPs from patients with eCRS for cluster 1, NPs and/or UT samples from patients with non-eCRS for cluster 2, and UTs from patients with non-CRS for cluster 3.

Conclusion

The results suggest that there are associations between type 2 inflammation/PGD2 and eCRS and also between type 3 inflammation/prostaglandin E2 and non-eCRS.

Innovative treatments for severe uncontrolled chronic rhinosinusitis with nasal polyps

INTRODUCTION

In recent years, endotypes of chronic rhinosinusitis (CRS) based on the underlying immune mechanisms provided a better understanding of this heterogeneous disease and are frequently applied in diagnosis and treatment.

AREAS COVERED

In this manuscript, we aim to review novel treatment approaches for this often uncontrolled disease and highlight endotype-driven medical algorithms that could be beneficial in daily clinical practice.

EXPERT OPINION

With the development of endotyping and the mucosal inflammatory concept, several type 2-targeted biologics and surgical options are nowadays available for treating CRS. However, a better understanding based on clinical trials and real-life experience in daily practice is needed to optimize patient selection, biological drug selection, treatment duration, prediction, and long-term follow-up strategies. Indirect comparison analysis suggested that dupilumab might be the most effective biologic for treating CRS with nasal polyps, but the role and timing of surgery remain unclear. More real-life studies and comparative trials are needed for the optimal integration of biologics into clinical pathways in combination with established treatment approaches such as nasal and oral glucocorticosteroids and adequate surgery to provide long-term perspectives.

A review of current biomarkers in chronic rhinosinusitis with or without nasal polyps

INTRODUCTION

Chronic rhinosinusitis (CRS) is a heterogeneous disease with a variety of cellular and molecular pathophysiologic mechanisms. Biomarkers have been explored in CRS using various phenotypes, such as polyp recurrence after surgery. Recently, the presence of regiotype in CRS with nasal polyps (CRSwNP) and the introduction of biologics for the treatment of CRSwNP has indicated the importance of endotypes, and there is a need to elucidate endotype-based biomarkers.

AREAS COVERED

Biomarkers for eosinophilic CRS, nasal polyps, disease severity, and polyp recurrence have been identified. Additionally, endotypes are being identified for CRSwNP and CRS without nasal polyps using cluster analysis, an unsupervised learning technique.

EXPERT OPINION

Endotypes in CRS have still being established, and biomarkers capable of identifying endotypes of CRS are not yet clear. When identifying endotype-based biomarkers, it is necessary to first identify endotypes clarified by cluster analysis for outcomes. With the application of machine learning, the idea of predicting outcomes using a combination of multiple integrated biomarkers, rather than a single biomarker, will become mainstream.

The functional role and the clinical application of periostin in chronic rhinosinusitis

INTRODUCTION

Chronic rhinosinusitis (CRS) comprises several heterogenous groups, now classified based on endotype more often than on phenotype. A number of studies aimed at finding a useful biomarker for type 2 CRS suggest that periostin is a promising surrogate.

AREAS COVERED

A comprehensive overview of the clinical significance of tissue periostin expression and serum periostin in CRS patients is provided. The effects of comorbid asthma on serum periostin and samples other than serum in which periostin can be detected in CRS patients are also discussed. Moreover, the functional roles of periostin in CRS pathogenesis are summarized.

EXPERT OPINION

The position of periostin as a signature biomarker of type 2 CRS has been well established, enabling us to classify CRS patients by endotyping. Serum periostin is useful not only for endotyping CRS patients, but also for estimating disease severity, comorbidity, prognosis, and response to treatment, and in particular, predicting recurrence after surgery. However, it remains to be addressed how we apply serum periostin to using biologics for CRS patients. Further studies aimed at showing periostin to be a therapeutic target for CRS are awaited.

Identification of Inflammatory Endotypes by Clinical Characteristics and Nasal Secretion Biomarkers in Chronic Rhinosinusitis with Nasal Polyps

INTRODUCTION

The emergency of biologics and surgical techniques targeting the specific inflammatory endotype in chronic rhinosinusitis with nasal polyps (CRSwNP) asks for efficient identification of patients with different endotypes. Although mucosal IL-4, IL-5, IL-13, and IgE have been used to define type 2 (T2) inflammation, the optimal one remains unclear. In this study, we aimed to determine the optimal anchor for T2 inflammation and identify clinical characteristics and nasal secretion biomarkers predicting different endotypes in CRSwNP.

METHODS

Six mediators in sinonasal tissue and 36 mediators in nasal secretion samples were detected by the Bio-Plex suspension array system. Mucosal IFN-γ and IL-17A levels were used to define the T1 and T3 endotype, respectively. The efficacy of mucosal IL-4, IL-5, IL-13, and IgE to define the T2 endotype was compared. The power of clinical characteristics and nasal secretion biomarkers to predict the T1, T2, and T3 endotype was analyzed.

RESULTS

Among mucosal IL-4, IL-5, IL-13, and IgE, IL-13 was the best one to coincide with the expression of other T2 biomarkers. A combination of atopy, facial pain symptom score, ethmoid/maxillary computed tomography score ratio, and blood eosinophil percentage had a moderate predictive performance for T2 endotype (area under the receiver operating curve [AUC] = 0.815), comparable to that of nasal secretion IL-5 (AUC = 0.819). For the T3 endotype, nasal secretion IL-1Rα identified it with an AUC value of 0.756. No efficient marker for the T1 endotype was found.

CONCLUSION

IL-13 is a primary anchor for the T2 endotype in CRSwNP. Clinical characteristics and nasal secretion biomarkers are helpful for identifying the T2 and T3 endotype of CRSwNP.

Transcriptomic Differentiation of Phenotypes in Chronic Rhinosinusitis and Its Implications for Understanding the Underlying Mechanisms

Chronic rhinosinusitis (CRS) is a multifaceted disease with variable clinical courses and outcomes. We aimed to determine CRS-associated nasal-tissue transcriptome in clinically well-characterized and phenotyped individuals, to gain a novel insight into the biological pathways of the disease. RNA-sequencing of tissue samples of patients with CRS with polyps (CRSwNP), without polyps (CRSsNP), and controls were performed. Characterization of differently expressed genes (DEGs) and functional and pathway analysis was undertaken. We identified 782 common CRS-associated nasal-tissue DEGs, while 375 and 328 DEGs were CRSwNP- and CRSsNP-specific, respectively. Common key DEGs were found to be involved in dendritic cell maturation, the neuroinflammation pathway, and the inhibition of the matrix metalloproteinases. Distinct CRSwNP-specific DEGs were involved in NF-kβ canonical pathways, Toll-like receptor signaling, HIF1α regulation, and the Th2 pathway. CRSsNP involved the NFAT pathway and changes in the calcium pathway. Our findings offer new insights into the common and distinct molecular mechanisms underlying CRSwNP and CRSsNP, providing further understanding of the complex pathophysiology of the CRS, with future research directions for novel treatment strategies.

Treatment Strategy of Uncontrolled Chronic Rhinosinusitis with Nasal Polyps: A Review of Recent Evidence

Chronic rhinosinusitis (CRS) is recognized as a heterogeneous disease with a wide range of clinical features, resulting in significant morbidity and cost to the healthcare system. While the phenotypic classification is determined by the presence or absence of nasal polyps and comorbidities, the endotype classification has been established based on molecular biomarkers or specific mechanisms. Research on CRS has now developed based on information based on three major endotypes: types 1, 2, and 3. Recently, biological therapies targeting type 2 inflammation have been clinically expanded and may be applied to other inflammatory endotypes in the future. The purpose of this review is to discuss the treatment options according to the type of CRS and summarize recent studies on new therapeutic approaches for patients with uncontrolled CRS with nasal polyps.

Immunological mechanisms and treatable traits of chronic rhinosinusitis in Asia: A narrative review

OBJECTIVES

To review the current literature on immunological mechanisms and treatable traits of chronic rhinosinusitis (CRS) in Asia.

DESIGN

This is a narrative review of published data on the immunological mechanisms and treatable traits of CRS in Asia. Published English literature on CRS in Asian and Western countries was reviewed. Where available, the data extracted included epidemiology, immunology, bacterium, phenotype, endotype and treatment.

RESULTS AND CONCLUSION

CRS is a heterogeneous disease characterised by persistent locoregional mucosal inflammation of the paranasal sinuses. The inflammatory signatures of CRS vary across patients with distinct racial and ethnic backgrounds and geographic areas. Compared to CRS patients in Western countries, Asian CRS patients display less eosinophilic and Type 2 inflammation, which is associated with lower asthma and allergic rhinitis comorbidities. In contrast, Asian patients with CRS have more prominent non-eosinophilic inflammation than those in Western countries. In addition, Asian CRS patients may have different bacterial colonisation than patients in Western countries. Our review suggests that the distinct immunological mechanisms between Asian and Western CRS patients may influence the clinical phenotype, responses to treatment and outcomes. The treatable trait is a new strategy and therapeutic target identified by phenotype or endotype and has been proposed as a new paradigm for the management of diseases. Improved understanding of CRS phenotypic and endotypic heterogeneity and incorporation of treatable traits into clinical care pathways may facilitate more effective selections of therapeutic interventions, including surgery and biologics.

B Lineage Cells and IgE in Allergic Rhinitis and CRSwNP and the Role of Omalizumab Treatment

BACKGROUND

Allergic rhinitis (AR) and chronic rhinosinusitis (CRS) are two prevalent nasal diseases where both type 2 inflammation and immunoglobulin E (IgE) may play important roles. Although they can exist independently or comorbidly, subtle but important differences exist in immunopathogenesis.

OBJECTIVE

To summarize current knowledge of pathophysiological roles of B lineage cells and IgE in AR and CRS with nasal polyps (CRSwNP).

METHODS

Searched PubMed database, reviewed AR and CRSwNP-related literature, and discussed disease diagnosis, comorbidity, epidemiology, pathophysiology, and treatment. Similarities and differences in B-cell biology and IgE are compared in the 2 conditions.

RESULTS

Both AR and CRSwNP have evidence for pathological type 2 inflammation, B-cell activation and differentiation, and IgE production. However, distinctions exist in the clinical and serological profiles at diagnosis, as well as treatments utilized. B-cell activation in AR may more frequently be regulated in the germinal center of lymphoid follicles, whereas CRSwNP may occur via extrafollicular pathways although controversies remain in these initial activating events. Oligoclonal and antigen-specific IgE maybe predominate in AR, but polyclonal and antigen-nonspecific IgE may predominate in CRSwNP. Omalizumab has been shown efficacious in treating both AR and CRSwNP in multiple clinical trials but is the only Food and Drug Administration-approved anti-IgE biologic to treat CRSwNP or allergic asthma. Staphylococcus aureus frequently colonizes the nasal airway and has the ability to activate type two responses including B-cell responses although the extent to which it modulates AR and CRSwNP disease severity is being investigated.

CONCLUSION

This review highlights current knowledge of the roles of B cells and IgE in the pathogenesis of AR and CRSwNP and a small comparison between the 2 diseases. More systemic studies should be done to elevate the understanding of these diseases and their treatment.

Endotyping Chronic Rhinosinusitis with Nasal Polyps: Understanding Inflammation Beyond Phenotypes

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogenous group of inflammatory conditions impacting the nose and paranasal sinuses. Our understanding of the underlying pathobiology of CRSwNP has substantially improved due to ongoing translational research efforts. Advances in treatment options, including targeted respiratory biologic therapy for CRSwNP, allow for more personalized approaches for CRSwNP patient care. Patients with CRSwNP are typically classified to one or more endotype based on the presence of type 1, type 2, and type 3 inflammation. This review will discuss recent advances in our understanding of CRSwNP and how this may impact current and future treatment approaches for patients with CRSwNP.

Functional Alteration and Differential Expression of the Bitter Taste Receptor T2R38 in Human Paranasal Sinus in Patients with Chronic Rhinosinusitis

The bitter taste receptors (T2Rs) expressed in human sinonasal mucosae are known to elicit innate immune responses involving the release of nitric oxide (NO). We investigated the expression and distribution of two T2Rs, T2R14 and T2R38, in patients with chronic rhinosinusitis (CRS) and correlated the results with fractional exhaled NO (FeNO) levels and genotype of the T2R38 gene (TAS2R38). Using the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) phenotypic criteria, we identified CRS patients as either eosinophilic (ECRS, n = 36) or non-eosinophilic (non-ECRS, n = 56) patients and compared these groups with 51 non-CRS subjects. Mucosal specimens from the ethmoid sinus, nasal polyps, and inferior turbinate were collected from all subjects, together with blood samples, for RT-PCR analysis, immunostaining, and single nucleotide polymorphism (SNP) typing. We observed significant downregulation of T2R38 mRNA levels in the ethmoid mucosa of non-ECRS patients and in the nasal polyps of ECRS patients. No significant differences in T2R14 or T2R38 mRNA levels were found among the inferior turbinate mucosae of the three groups. Positive T2R38 immunoreactivity was localized mainly in epithelial ciliated cells, whereas secretary goblet cells generally showed lack of staining. The patients in the non-ECRS group showed significantly lower oral and nasal FeNO levels compared with the control group. There was a trend towards higher CRS prevalence in the PAV/AVI and AVI/AVI genotype groups as compared to the PAV/PAV group. Our findings reveal complex but important roles of T2R38 function in ciliated cells associated with specific CRS phenotypes, suggesting the T2R38 pathway as a potential therapeutic target for promotion of endogenous defense mechanisms.

Long-term efficacy of dupilumab in asthma with or without chronic rhinosinusitis and nasal polyps

BACKGROUND

Coexisting chronic rhinosinusitis and nasal polyps (CRS-NPs) substantially increases the disease burden of asthma. Dupilumab, a fully human monoclonal antibody, has established efficacy and an acceptable safety profile in asthma and CRS with NP.

OBJECTIVE

To evaluate long-term dupilumab efficacy in TRAVERSE (NCT02134028) patients with uncontrolled, moderate-to-severe (QUEST) or oral corticosteroid (OCS)-dependent (VENTURE) asthma with or without coexisting CRS-NP.

METHODS

In TRAVERSE, 317 of 1530 (21%) QUEST and 61 of 187 (48%) VENTURE patients had self-reported CRS-NP; they received subcutaneous 300 mg dupilumab every 2 weeks up to 96 weeks. Patients were categorized by parent study treatment group (placebo/dupilumab, dupilumab/dupilumab). End points included annualized asthma exacerbation rates and mean change from parent study baseline in prebronchodilator forced expiratory volume in 1 second, Asthma Control Questionnaire 5 score, Asthma Quality of Life Questionnaire score, and OCS dose.

RESULTS

Patients with coexisting CRS-NP had higher OCS dose and a history of more exacerbations. Concluding TRAVERSE, exacerbation rates decreased from 2.39 to 0.32 and 2.32 to 0.35 in dupilumab/dupilumab and 2.36 to 0.41 and 2.36 to 0.45 in placebo/dupilumab by week 96 from QUEST and VENTURE baselines, respectively. Non-CRS-NP results were similar. Improvements in forced expiratory volume in 1 second, Asthma Control Questionnaire 5 score, and Asthma Quality of Life Questionnaire score during parent studies were maintained in TRAVERSE; placebo/dupilumab patients achieved similar improvements to dupilumab/dupilumab by week 48. By week 96, 71% and 39% of OCS-dependent patients with CRS-NP and 83% and 47% without CRS-NP treated with dupilumab/dupilumab and placebo/dupilumab, respectively, stopped OCS.

CONCLUSION

Long-term dupilumab efficacy was maintained in patients with asthma with or without self-reported coexisting CRS-NP, including OCS-sparing effects observed in OCS-dependent severe asthma.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02528214, NCT02414854, and NCT02134028.

Impact of Chronic Rhinosinusitis with Nasal Polyposis on IL-12 and IL-8

Introduction

The pathophysiology of Chronic Rhinosinusitis is coordinated by distinct inflammatory reactions in different individuals. Inflammatory environments with a predominance of Th2 lymphocytes tend also to be rich in eosinophils. These environments are common during the formation of nasal polyps associated with aspirin intolerance, which is also marked by an increase in inflammatory mediators, especially IL-4, IL-5, and IL-13. Despite the significance of these inflammatory mediators, the relevance of IL-12 subunits' presence within eosinophilic nasal polyps, however, has been less studied. The current study aims to evaluate the presence of IL-12 subunits, IL-12p40 and IL-12p70, in eosinophilic nasal polyps and their correlations with IL-8 presence.

Materials and Methods

We compared the concentrations of IL-8, IL12p40, and IL12p70 among samples of eosinophilic nasal polypoid tissue, eosinophilic nasal polypoid tissue associated with aspirin intolerance, and healthy nasal mucosa, using an indirect immunoassay (ELISA) kit.

Results

When compared to healthy nasal mucosa, there was a lower concentration of IL-8 in Chronic Rhinosinusitis with Nasal Polyp (CRSwNP) tissue. Aspirin Intolerant polypoid tissue also presented a lower concentration of IL-12 subunits compared to healthy nasal mucosa. There was no significant correlation between IL-8 and IL-12 in the eosinophilic polypoid conditions.

Conclusion

In CRSwNP, there is a reduction in IL-8 and IL-12 subunits compared to control, with a lack of correlation between IL-12 and IL-8. The lack of correlation can be justified by a type two inflammatory storm environment.

Persistent discharge or edema after endoscopic sinus surgery in patients with chronic rhinosinusitis is associated with a type 1 or 3 endotype

BACKGROUND

Patients with chronic rhinosinusitis (CRS) may have persistence of polyps, discharge, or edema after endoscopic sinus surgery (ESS). Inflammation in CRS can be classified into three endotypes, with the presence of polyps associated with the type 2 endotype. Here, we evaluate the endotypic underpinnings of discharge or edema without polyps after ESS.

METHODS

At a visit 6-12 months post ESS, patients underwent endoscopy and completed the CRS-PRO and SNOT-22. Luminex analysis of middle meatal mucus obtained at that visit was performed for IFN-γ, ECP, and IL-17a. Type 1, 2, and 3 endotypes were defined as greater than the 90th percentile expression of each marker, respectively, in controls. Wilcoxon rank-sum and chi-squared tests were used to compare cytokine levels and endotype prevalence between those with and without endoscopic findings.

RESULTS

A total of 122 CRS patients completed a clinical exam (median: 8.2 months post ESS). Of the 122 patients, 107 did not have polyps on endoscopy. Of these 107 patients, 48 had discharge, 44 had edema, and 46 had neither discharge nor edema. Compared with those patients without any findings, patients with discharge or edema reported significantly worse severity as measured by CRS-PRO (10.5 vs. 7.0, p = 0.009; 12.0 vs. 7.0, p < 0.001; respectively), and had higher post-ESS IFN-γ, ECP, and IL-17a. Patients with discharge had higher prevalence of only T1 and T3 endotypes, while patients with edema had higher prevalence of only the T3 endotype.

CONCLUSIONS

Post-ESS discharge or edema in the absence of polyps was associated with higher patient-reported outcome severity and was more strongly associated with type 1 or 3 inflammation.

A Decade of Clinical Advances in Chronic Rhinosinusitis: 2012-2022

The field of chronic rhinosinusitis (CRS) is constantly evolving. In the past 10 years, key advancements in basic and translational research as well as clinical studies have improved our understanding and management of CRS. Notably, treatment options have expanded to include novel therapeutic drugs, devices, and surgical techniques. Assessments of patient symptoms and their impact on quality of life have become more standardized. Progress has also been made in both determining the true prevalence of CRS and recognizing comorbidities that can impact CRS severity. Practice guidelines have also shifted from expert opinion to more data-driven analyses. This review highlights major clinical advancements made in the field of CRS over the past 10 years as well as identifies current gaps in knowledge that can form the basis for new areas of study over the next decade.

Sense of smell in chronic rhinosinusitis: A multicentric study on 811 patients

Introduction

The impairment of the sense of smell is often related to chronic rhinosinusitis (CRS) with or without nasal polyps (CRSwNP, CRSsNP). CRSwNP is a frequent condition that drastically worsens the quality of life of those affected; it has a higher prevalence than CRSsNP. CRSwNP patients experience severe loss of smell with earlier presentation and are more likely to experience recurrence of their symptoms, often requiring revision surgery.

Methods

The present study performed a multicentric data collection, enrolling 811 patients with CRS divided according to the inflammatory endotype (Type 2 and non-Type 2). All patients were referred for nasal endoscopy for the assessment of nasal polyposis using nasal polyp score (NPS); Sniffin' Sticks olfactory test were performed to measure olfactory function, and SNOT-22 (22-item sinonasal outcome test) questionnaire was used to assess patients' quality of life; allergic status was evaluated with skin prick test and nasal cytology completed the evaluation when available.

Results

Data showed that Type 2 inflammation is more common than non-type 2 (656 patients versus 155) and patients suffer from worse quality of life and nasal polyp score. Moreover, 86.1% of patients with Type 2 CRSwNP were affected by a dysfunction of the sense of smell while it involved a lesser percentage of non-Type 2 patients. Indeed, these data give us new information about type-2 inflammation patients' characteristics.

Discussion

The present study confirms that olfactory function weights on patients' QoL and it represents an important therapeutic goal that can also improve patients' compliance when achieved. In a future - and present - perspective of rhinological precision medicine, an impairment of the sense of smell could help the clinician to characterize patients better and to choose the best treatment available.

[Research progress of biomarkers in nasal secretions in endotypes diagnosis and clinical application of chronic rhinosinusitis]

With the development of studies on the endotypes of chronic rhinosinusitis （CRS） and the biomarkers of nasal secretions, the studies of CRS endotypes based on nasal secretion have become more abundant. This paper summarizes the endotypes classification of CRS, the collection methods of nasal secretion and the nasal secretion biomarkers related to the endotypes of CRS, in order to provide a reference for establishing the corresponding endotypes of CRS based on the nasal secretion biomarkers.

Immunopathologic Role of Eosinophils in Eosinophilic Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a diverse chronic inflammatory disease of the sinonasal mucosa. CRS manifests itself in a variety of clinical and immunologic patterns. The histological hallmark of eosinophilic CRS (ECRS) is eosinophil infiltration. ECRS is associated with severe disease severity, increased comorbidity, and a higher recurrence rate, as well as thick mucus production. Eosinophils play an important role in these ECRS clinical characteristics. Eosinophils are multipotential effector cells that contribute to host defense against nonphagocytable pathogens, as well as allergic and nonallergic inflammatory diseases. Eosinophils interact with Staphylococcus aureus, Staphylococcal enterotoxin B, and fungi, all of which were found in the tissue of CRS patients. These interactions activate Th2 immune responses in the sinonasal mucosa and exacerbate local inflammation. Activated eosinophils were discovered not only in the tissue but also in the sinonasal cavity secretion. Eosinophil extracellular traps (EETs) are extracellular microbes trapping and killing structures found in the secretions of CRS patients with intact granule protein and filamentous chromatic structures. At the same time, EET has a negative effect by causing an epithelial barrier defect. Eosinophils also influence the local tissue microenvironment by exchanging signals with other immune cells and structural cells. As a result, eosinophils are multifaceted leukocytes that contribute to various physiologic and pathologic processes of the upper respiratory mucosal immune system. The goal of this review is to summarize recent research on the immunopathologic properties and immunologic role of eosinophils in CRS.

Immunological Aspects of Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is related to persistent inflammation with a dysfunctional relationship between environmental agents and the host immune system. Disturbances in the functioning of the sinus mucosa lead to common clinical symptoms. The major processes involved in the pathogenesis of CRS include airway epithelial dysfunctions that are influenced by external and host-derived factors which activate multiple immunological mechanisms. The molecular bases for CRS remain unclear, although some factors commonly correspond to the disease: bacterial, fungal and viral infections, comorbidity diseases, genetic dysfunctions, and immunodeficiency. Additionally, air pollution leads increased severity of symptoms. CRS is a heterogeneous group of sinus diseases with different clinical courses and response to treatment. Immunological pathways vary depending on the endotype or genotype of the patient. The recent knowledge expansion into mechanisms underlying the pathogenesis of CRS is leading to a steadily increasing significance of precision medicine in the treatment of CRS. The purpose of this review is to summarize the current state of knowledge regarding the immunological aspects of CRS, which are essential for ensuring more effective treatment strategies.

Strong and consistent associations of precedent chronic rhinosinusitis with risk of non-cystic fibrosis bronchiectasis

BACKGROUND

Chronic rhinosinusitis (CRS) and bronchiectasis commonly co-occur, but most prior studies were not designed to evaluate temporality and causality.

OBJECTIVES

In a sample representing the general population in 37 counties in Pennsylvania, and thus the full spectrum of sinonasal and relevant lung diseases, we aimed to evaluate the temporality and strength of associations of CRS with non-cystic fibrosis bronchiectasis.

METHODS

We completed case-control analyses for each of 3 primary bronchiectasis case finding methods. We used electronic health records to identify CRS and bronchiectasis with diagnoses, procedure orders, and/or specific text in sinus or chest computerized tomography scan radiology reports. The controls never had any indication of bronchiectasis and were frequency-matched to the 3 bronchiectasis groups on the basis of age, sex, and encounter year. There were 5,329 unique persons with bronchiectasis and 33,363 without bronchiectasis in the 3 analyses. Important co-occurring conditions were identified with diagnoses, medication orders, and encounter types. Logistic regression was used to evaluate associations (odds ratios [ORs] and 95% CIs) of CRS with bronchiectasis while adjusting for confounding variables.

RESULTS

In adjusted analyses, CRS was consistently and strongly associated with all 3 bronchiectasis definitions. The strongest associations for CRS (ORs and 95% CIs) were those that were based on the text of sinus computerized tomography scan reports; the associations were generally stronger for CRS without nasal polyps (eg, OR = 4.46 [95% CI = 2.09-9.51] for diagnosis-based bronchiectasis). On average, CRS was identified more than 6 years before bronchiectasis.

CONCLUSION

Precedent CRS was strongly and consistently associated with increased risk of bronchiectasis.

An Integrated Analysis of Inflammatory Endotypes and Clinical Characteristics in Chronic Rhinosinusitis with Nasal Polyps

Objective

Chronic rhinosinusitis with nasal polyps (CRSwNP) is mainly characterised by type 1 (T1), type 2 (T2) and type 3 (T3) inflammatory endotypes. However, correlations between inflammatory endotypes and clinical features in CRSwNP have not been demonstrated sufficiently. This study aimed to determine the endotype-phenotype associations in CRSwNP.

Methods

Clinical data of 31 control subjects and 106 CRSwNP patients were analysed. Interferon (IFN)-γ (T1), Charcot-Leyden crystal galectin (CLC) (T2) and Interleukin (IL)-17A (T3) were used as biomarkers to identify the inflammatory endotypes.

Results

The mRNA expression level of IFN-γ was positively correlated with IL-17A (r = 0.817; P < 0.0001). Headache/facial pain (P = 0.039) was associated with T1 endotype. Smell loss (P = 0.025) was associated with T2 endotype. Purulent rhinorrhea (P = 0.001) was associated with T3 endotype. Atopy (P = 0.030), asthma (P = 0.005) and recurrence (P = 0.022) were more frequent in T2 endotype. Total Symptom Scores (TSS) of T2 (P < 0.001) and T3 (P = 0.009) endotype were higher than non-T2 and non-T3, respectively. Sino Nasal Outcome Test-22 (SNOT-22) total scores of T3 (P = 0.054) endotype were higher than non-T3.

Conclusion

Identifications of endotype-phenotype associations are useful in clinical diagnoses and targeted therapies for patients with CRSwNP.

Prognostic factors for polyp recurrence in chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps is frequently managed with endoscopic sinus surgery (ESS). Prior studies describe individual clinical variables and eosinophil density measures as prognostic for polyp recurrence (PR). However, the relative prognostic significance of these have not been extensively investigated.

OBJECTIVES

We sought to evaluate the impact of PR on measures of disease severity post-ESS and quantify the prognostic value of various clinical variables and biomarkers.

METHODS

Ninety-four patients with chronic rhinosinusitis with nasal polyps and prospectively biobanked polyp homogenates at the time of ESS were recruited 2 to 5 years post-ESS. Patients were evaluated with patient-reported outcome measures and endoscopic and radiographic scoring pre- and post-ESS. Biomarkers in polyp homogenates were measured with ELISA and Luminex. Relaxed least absolute shrinkage and selection operator regression optimized predictive clinical, biomarker, and combined models. Model performance was assessed using receiver-operating characteristic curve and random forest analysis.

RESULTS

PR was found in 39.4% of patients, despite significant improvements in modified Lund-Mackay (MLM) radiographic and 22-item Sinonasal Outcomes Test scores (both P < .0001). PR was significantly associated with worse post-ESS MLM, modified Lund-Kennedy, and 22-item Sinonasal Outcomes Test scores. Relaxed least absolute shrinkage and selection operator identified 2 clinical predictors (area under the curve = 0.79) and 3 biomarkers (area under the curve = 0.78) that were prognostic for PR. When combined, the model incorporating these pre-ESS factors: MLM, asthma, eosinophil cationic protein, anti-double-stranded DNA IgG, and IL-5 improved PR predictive accuracy to area under the curve of 0.89. Random forest analysis identified and validated each of the 5 variables as the strongest predictors of PR.

CONCLUSIONS

PR had strong associations with patient-reported outcome measures, endoscopic and radiographic severity. A combined model comprised of eosinophil cationic protein, IL-5, pre-ESS MLM, asthma, and anti-double-stranded DNA IgG could accurately predict PR.

Anti-phospholipid antibodies are elevated and functionally active in chronic rhinosinusitis with nasal polyps

BACKGROUND

Polyps from patients with chronic rhinosinusitis with nasal polyps (CRSwNP) contain increased levels of autoreactive antibodies, B cells and fibrin deposition. Anti-phospholipid antibodies (APA) are autoantibodies known to cause thrombosis but have not been implicated in chronic rhinosinusitis (CRS).

OBJECTIVE

To compare APA levels (anti-cardiolipin, anti-phosphatidylethanolamine (anti-PE), and anti-β2 -glycoprotein (anti-B2GP)) in nasal polyp (NP) tissue with tissue from control and CRS without nasal polyp (CRSsNP) patients, we tested whether NP antibodies affect coagulation, and correlate APAs with anti-dsDNA IgG and markers of coagulation.

METHODS

Patient specimens were assayed for APA IgG, anti-dsDNA IgG and thrombin-anti-thrombin (TaT) complex by ELISA. Antibodies from a subset of specimens were tested for modified activated partial thromboplastin time (aPTT) measured on an optical-mechanical coagulometer.

RESULTS

Anti-cardiolipin IgG in NP was 5-fold higher than control tissue (p < .0001). NP antibodies prolonged aPTT compared to control tissue antibodies at 400 µg/mL (36.7 s vs. 33.8 s, p = .024) and 600 µg/mL (40.9 s vs. 34.7 s, p = .0037). Anti-PE IgG antibodies were increased in NP (p = .027), but anti-B2GP IgG was not significantly higher (p = .084). All APAs correlated with anti-dsDNA IgG levels, which were also elevated (R = .77, .71 and .54, respectively, for anti-cardiolipin, anti-PE, and anti-B2GP; all p < .001), but only anti-cardiolipin (R = .50, p = .0185) and anti-PE (R = 0.45, p = .037) correlated with TaT complex levels.

CONCLUSIONS

APA IgG antibodies are increased in NP and correlate with autoreactive tissue antibodies. NP antibodies have in vitro anti-coagulant activity similar to those observed in anti-phospholipid syndrome, suggesting that they may have pro-coagulant effects in polyp tissue.

Efficacy of an oral CRTH2 antagonist (AZD1981) in the treatment of chronic rhinosinusitis with nasal polyps in adults: A randomized controlled clinical trial

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a type 2 inflammatory disease of the upper airways. AZD1981 is a selective antagonist of chemoattractant receptor-homologous molecule expressed on T helper type 2 and other type 2 cells, including innate lymphoid cells type 2, eosinophils, and basophils.

OBJECTIVE

To evaluate the efficacy of AZD1981 in reducing nasal polyp size when added to intranasal corticosteroids in adult patients with CRSwNP.

METHODS

Eighty-one subjects (18-70 years of age) with CRSwNP were recruited and screened for trial eligibility from allergy and otolaryngology clinics from a single tertiary care site between June 2016 and August 2019. Eligible patients were randomized in a double-blind fashion to receive either AZD1981 (n = 22) or placebo (n = 21) orally three times a day for 12 weeks, added to intranasal corticosteroids. The primary endpoint was a change in nasal polyp score (NPS) at 12 weeks. Secondary endpoints included improvement in sinus computed tomography using Lund Mackay scoring, symptoms using visual analog scale, quality of life using Sino Nasal Outcome Test-22, and the Brief Smell Identification Test.

RESULTS

Forty-three patients met the inclusion criteria and were enrolled. At 12 weeks, there was no difference in NPS change in the AZD1981 arm (mean 0, standard error 0.34, n = 15) compared with placebo (mean 0.20, standard error 0.36, n = 17); mean difference -0.20 (95% confidence interval: -1.21, 0.81; p = .69). No significant differences were observed for Lund Mackay score, symptoms, quality of life, or smell test. AZD1981 was well tolerated except for one case of hypersensitivity reaction.

CONCLUSION

In patients with CRSwNP, the addition of AZD1981 to intranasal corticosteroids did not change nasal polyp size, radiographic scores, symptoms, or disease-specific quality of life.

Improving predictability of IgE-high type 2 chronic sinusitis with nasal polyps in the biologic era

BACKGROUND

Chronic rhinosinusitis (CRS) is an inflammatory disease that may require biological therapy. Omalizumab is an anti-IgE biologic that was recently approved by the FDA and Health Canada for use in severe CRS with nasal polyps (CRSwNP) recalcitrant to intranasal corticosteroids. Dosing is based on weight and pre-treatment serum IgE, with elevated levels of the latter being an indication for biologic treatment according to EPOS and EUFOREA guidelines. The goal of this study was to identify variables that predict IgE-high type 2 inflammation and serve as indicators for biologic treatment in CRS.

METHODS

Patients ≥ 19 yo diagnosed with CRS undergoing functional endoscopic sinus surgery were included retrospectively. Demographics, past medical history, preoperative blood work, Lund-Mackay (LM), Lund Kennedy (LK), and SNOT-22 scores were extracted. Descriptive statistics and binary logistic regression analyses were conducted. Model superiority was based on Nagelkerke R2 scores and receiver operating characteristic curves.

RESULTS

Sixty-five patients, average age 49.96 ± 13.59 years, were included. Sixty-one binary logistic regression models for elevated serum IgE were created. Among the top 3 models, the best model had sensitivity, specificity, positive predictive value and negative predictive values of 82.1, 69.2, 80.0, and 72.0. All performance measures except sensitivity exceeded the Canadian Biologics Guideline model. Serum eosinophils ≥ 300 cell/uL, CRSwNP and LM ≥ 17 increased the odds of elevated IgE.

CONCLUSIONS

IgE-high type-2 inflammation can be predicted by a model that includes eosinophil ≥ 300 cell/uL, CRSwNP, LM ≥ 17, asthma diagnosis and SNOT-22 ≥ 40. Patients meeting these parameters have a high pretest probability for elevated IgE and would benefit from IgE serology to determine qualification for omalizumab. This could reduce unwarranted IgE serology in patients with CRSwNP but also target a patient population for further workup that will lead to optimization of resource allocation and improve healthcare equity in rural and remote areas within Canada.