Role of tissue eosinophils in chronic rhinosinusitis-associated olfactory loss

Thymic Stromal Lymphopoietin and Tezepelumab in Airway Diseases: From Physiological Role to Target Therapy

Thymic stromal lymphopoietin (TSLP), is a protein belonging to a class of epithelial cytokines commonly called alarmins, which also includes IL-25 and IL-33. Functionally, TSLP is a key player in the immune response to environmental insults, initiating a number of downstream inflammatory pathways. TSLP performs its role by binding to a high-affinity heteromeric complex composed of the thymic stromal lymphopoietin receptor (TSLPR) chain and IL-7Rα. In recent years, the important role of proinflammatory cytokines in the etiopathogenesis of various chronic diseases such as asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP), chronic obstructive pulmonary diseases (COPDs), and chronic spontaneous urticaria has been studied. Although alarmins have been found to be mainly implicated in the mechanisms of type 2 inflammation, studies on monoclonal antibodies against TSLP demonstrate partial efficacy even in patients whose inflammation is not definable as T2 and the so-called low T2. Tezepelumab is a human anti-TSLP antibody that prevents TSLP-TSLPR interactions. Several clinical trials are evaluating the safety and efficacy of Tezepelumab in various inflammatory disorders. In this review, we will highlight major recent advances in understanding the functional role of TSLP, its involvement in Th2-related diseases, and its suitability as a target for biological therapies.

Analysis of the Construction of a Predictive Model for Eosinophilic Chronic Rhinosinusitis

Purpose

This study aimed to determine indices to diagnose and predict eosinophilic chronic rhinosinusitis (ECRS) during the initial clinic visit.

Patients and Methods

We retrospectively analyzed 116 patients with chronic rhinosinusitis who underwent endoscopic sinus surgery and were classified according to the postoperative pathological diagnosis. General data and various clinical indicators were analyzed, and indicators with statistically significant differences between groups were further incorporated into a multivariate logistic regression to establish a comprehensive prediction model. The receiver operating characteristic (ROC) curve was used to compare the two significant valuable single factors from previous studies, the difference in CT scores between the ethmoid sinus and the sum difference of the maxillary sinus (EM difference) and the absolute value of peripheral blood eosinophil (bEOS), with a comprehensive prediction model.

Results

There were significant differences in history of allergic asthma (p < 0.001), visual analog scale (VAS) score (p=0.005), sino-nasal outcome test-22(SNOT-22) scale score (p=0.004), Lund-Mackay scale score (p=0.017), EM difference (p=0.002), percentage of bEOS (%)(p=0.001), and absolute value of bEOS (×109/L) (p=0.000) between the two groups (p< 0.05). The history of allergic disease, VAS and bEOS were screened out and included in the comprehensive prediction model. The area under the curve (AUC) of the comprehensive prediction model (0.804)> the AUC of the absolute value of the bEOS (0.764)>the AUC of the EM difference (0.655). The AUC of the EM difference and the comprehensive prediction model were statistically different (P=0.025). There was no statistical difference between the absolute value of bEOS and the AUC of the comprehensive prediction model.

Conclusion

The comprehensive prediction model covering the three aspects of allergic asthma history, VAS score, and bEOS count had the highest AUC compared to the other predictors and had good predictive power for the diagnosis of ECRS.

Eosinophil Peroxidase: A Biomarker for Eosinophilic Chronic Rhinosinusitis Agnostic of Polyp Status

OBJECTIVE

To evaluate eosinophil peroxidase (EPX) as a biomarker for tissue levels of eosinophilia, cytokines, and chemokines within chronic rhinosinusitis (CRS).

METHODS

Twenty-eight subjects undergoing sinonasal surgery were prospectively enrolled. Ethmoid tissue was analyzed with an in-house EPX immunoassay and a 48-plex cytokine-chemokine array. Clinical severity was assessed using SNOT-22 and Lund-Mackay scores. Subjects were grouped as follows: controls, polyp status (CRS with [CRSwNP] and without nasal polyps [CRSsNP]), tissue eosinophilia (eosinophilic CRS [eCRS], non-eosinophilic CRS [neCRS]), or combinations thereof (eCRSwNP, eCRSsNP, neCRSsNP). eCRS was defined as >10 eosinophils per high power field (HPF). Subjects without CRS or asthma were enrolled as controls.

RESULTS

EPX was elevated in CRSwNP compared to control (p = 0.007), in eCRS compared to neCRS (p = 0.002), and in eCRSwNP along with eCRSsNP compared to neCRSsNP (p = 0.023, p = 0.015, respectively). eCRS displayed elevated IL-5 compared to neCRS (p = 0.005). No significant differences in EPX or IL-5 were observed between eCRSwNP and eCRSsNP. IL-5 was elevated in eCRSwNP (p = 0.019) compared neCRSsNP. Area under the receiver operator characteristic curve was 0.938 (95% CI, 0.835-1.00) for EPX and tissue eosinophilia, with an optimal cut-point of 470 ng/mL being 100% specific and 81.25% sensitive for tissue eosinophilia. Linear regression revealed a strong correlation between EPX and IL-5 (R2  = 0.64, p < 0.001). Comparing EPX and IL-5, only EPX displayed significant correlation with SNOT-22 (p = 0.04) and Lund-Mackay score (p = 0.004).

CONCLUSION

EPX is associated with tissue eosinophilia in CRS patients regardless of polyp status. EPX correlates with IL-5 and could be potentially considered a biomarker for anti-IL-5 therapies.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:69-78, 2024.

Olfactory cleft mucus eosinophil-derived neurotoxin better reflects olfactory loss than blood eosinophil counts in patients with chronic rhinosinusitis

BACKGROUND

Eosinophils are associated with olfactory dysfunction in chronic rhinosinusitis (CRS) and eosinophil-derived neurotoxin (EDN) is a sensitive marker of intense eosinophil activation. This study aimed to analyze olfactory cleft mucus and olfactory mucosa EDN levels and their association with olfactory dysfunction in CRS.

METHODS

We prospectively recruited 150 patients with CRS electing endoscopic sinus surgery and 25 healthy controls. Both superior turbinate biopsy specimens and olfactory cleft mucus were collected to analyze EDN levels. Sniffin' Sticks test scores, olfactory cleft computed tomography (CT) scores, and olfactory cleft endoscopy scale (OCES) were obtained. Multivariable logistic regression analysis was applied to analyze the predictability of EDN levels for olfactory dysfunction in CRS.

RESULTS

Chronic rhinosinusitis with olfactory dysfunction presented significantly higher olfactory mucosa (p = 0.016) and olfactory cleft mucus (p < 0.001) EDN levels than CRS without olfactory dysfunction. Mucus EDN levels were positively correlated with blood eosinophils (r = 0.625, p = 0.002), olfactory cleft CT scores (r = 0.738, p < 0.001), and OCES (r = 0.605, p = 0.004) in CRS. Furthermore, mucus EDN levels were significantly negatively correlated with threshold, discrimination, and identification (TDI) (r = -0.688), olfactory threshold (r = -0.606), olfactory discrimination (r = -0.608), and olfactory identification (r = -0.697) scores. After adjusting for patient demographics and comorbidities, mucus EDN levels were significantly associated with olfactory dysfunction in CRS (odds ratio = 2.162; p = 0.027). Mucus EDN levels showed a significantly better performance for predicting olfactory dysfunction than blood eosinophil counts (area under the curve, 0.873 vs. 0.764, p = 0.024).

CONCLUSION

Olfactory cleft mucus EDN level may be a better biomarker for predicting olfactory dysfunction in CRS than blood eosinophil counts.

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.

[Artificial intelligence-assisted prediction of olfactory disorders in patients with chronic rhinosinusitis]

Objective:To analyze the influencing factors and perform the prediction of olfactory disorders in patients with chronic rhinosinusitis（CRS） based on artificial intelligence. Methods:The data of 75 patients with CRS who underwent nasal endoscopic surgery from October 2021 to February 2023 in the Department of Otorhinolaryngology Head and Neck Surgery, the Third Affiliated Hospital of Sun Yat-sen University were analyzed retrospectively. There were 53 males and 22 females enrolled in the study, with a median age of 42.0 years old. The CRS intelligent microscope interpretation system was used to calculate the proportion of area glands and blood vessels occupy in the pathological sections of each patient, and the absolute value and proportion of eosinophils, lymphocytes, plasma cells and neutrophils. The patients were grouped according to the results of the Sniffin' Sticks smell test, and the clinical baseline data, differences in nasal mucosal histopathological characteristics, laboratory test indicators and sinus CT were compared between the groups. Determine the independent influencing factors of olfactory disorders and receiver operating characteristic curves（ROC） were used to evaluate the performance of the prediction model. Statistical analysis was performed using SPSS 25.0 software. Results:Among the 75 CRS patients, 25 cases（33.3%） had normal olfaction and 50 cases（66.7%） had olfactory disorders. Multivariate Logistic regression analysis showed that tissue eosinophils percentage（OR=1.032, 95%CI 1.002-1.064, P=0.036）, Questionnaire of olfactory disorders-Negative statement（QOD-NS）（OR=1.079, 95%CI 1.004-1.160, P=0.040） and Anterior olfactory cleft score（AOCS）（OR=2.672, 95%CI 1.480-4.827, P=0.001） were independent risk factors for olfactory disorders in CRS patients. Further research found that the area under the ROC curve（AUC） of the combined prediction model established by the tissue eosinophil percentage, QOD-NS and AOCS was 0.836（95%CI 0.748-0.924, P<0.001）, which is better than the above single factor prediction model in predicting olfactory disorders in CRS. Conclusion:Based on pathological artificial intelligence, tissue eosinophil percentage, QOD-NS and AOCS are independent risk factors for olfactory disorders in CRS patients, and the combination of the three factors has a good predictive effect on CRS olfactory disorders.

Clinical Characteristics of Eosinophilic Chronic Rhinosinusitis with Nasal Polyps in Adolescents

Introduction

Eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) is frequently associated with greater inflammation, poorer prognosis, and a high recurrence rate after sinus surgery.

Objective

This study evaluated the clinical and imaging characteristics of eosinophilic CRSwNP in patients aged 12-17.

Methods

We retrospectively enrolled 139 patients aged 12-17 with bilateral CRSwNP. Clinical characteristics, computed tomography (CT) features, tissue eosinophil counts, and eosinophil activity were evaluated.

Results

Twenty-three (16.5%) patients had recurrent nasal polyps that required revision surgery. Patients requiring revision surgery had higher tissue eosinophil infiltration in the sinus mucosa than those not requiring revision surgery. The optimal cut-off value to distinguish the need for revision surgery was a tissue eosinophil count > 21.5/high-power field determined by the receiver operating characteristic curve. The Lund-Mackay and olfactory cleft opacification scores on CT images were significant predictors of tissue eosinophil count in the univariate analysis, and only olfactory opacification scores remained statistically significant in the multivariate analysis.

Conclusion

This study revealed that the CT feature of the olfactory cleft opacification score could be a significant characteristic of eosinophilic CRSwNP in adolescents.

Efficacy and safety of CM310 in severe eosinophilic chronic rhinosinusitis with nasal polyps (CROWNS-1): a multicentre, randomised, double-blind, placebo-controlled phase 2 clinical trial

Background

Severe eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) remains the most relapsed subtype of uncontrolled CRSwNP. CM310, a humanised anti-interleukin (IL)-4 receptor alpha monoclonal antibody, inhibits IL-4 and IL-13 signaling which underlying eosinophilic inflammation. This study aims to evaluate the efficacy and safety of CM310 in patients with severe ECRSwNP.

Methods

A multicentre, randomised, double-blind, and placebo-controlled phase 2 clinical trial was conducted. 56 eligible adult patients with severe ECRSwNP were randomised 1:1 to receive subcutaneously either CM310 (300 mg) or placebo every 2 weeks under the background therapy of mometasone furoate nasal spray (MFNS) for 16 weeks, with 8 weeks of follow-up. Coprimary endpoints included the changes from baseline in nasal polyp score (NPS) and nasal congestion score (NCS) at week 16. Key secondary endpoints included sinus Lund-Mackay CT score, change in sinus volume occupied by disease, University of Pennsylvania Smell Identification Test score, 22-item Sino-nasal Outcome Test score, and total symptom score. Safety, pharmacodynamics, and changes in type 2 inflammation biomarkers were assessed. This study is registered with ClinicalTrials.gov, NCT04805398.

Findings

Between April 6, 2021, and March 18, 2022, 27 patients respectively in both the CM310 and placebo groups completed the study. Findings suggested that CM310 improved the coprimary efficacy endpoints of decreasing nasal polyp size and alleviating nasal congestion compared with the placebo. Least squares (LS) mean differences (CM310 vs placebo) of change from baseline in NPS and NCS at week 16 were -2.1 (95% CI -2.9, -1.4; p < 0.0001) and -0.9 (95% CI -1.4, -0.5; p < 0.0001), respectively. Sinus CT scan revealed that Lund-Mackay CT score (LS mean difference [95% CI] -7.6, [-9.4, -5.8]; p < 0.0001) and sinus volume occupied by disease (LS mean difference [95% CI] -37%, [-47%, -28%]; p < 0.0001) were significantly improved with CM310 compared with placebo. In addition, CM310 significantly relieved the daily symptoms of patients with CRSwNP and improved their quality of life reflected by the improvements in the TSS (-2.6 [95% CI -3.5, -1.6]), UPSIT (10.4 [95% CI 6.8, 14.0]) and SNOT-22 score (-19.1 [95% CI -29.8, -8.5]). Compared with placebo, CM310 administration significantly reduced type 2-related biomarkers including the serum TARC and total IgE, and tissue eosinophils. The most common adverse events were upper respiratory tract infection, blood cholesterol increased, and tinnitus, but none were considered drug-related.

Interpretation

These findings support CM310 as an effective additional treatment option to the standard of care in patients with severe ECRSwNP.

Funding

KeyMed Biosciences (Chengdu) Limited.

Olfaction Now and in the Future in CRSwNP

BACKGROUND

Chronic rhinosinusitis (CRS) is the leading cause of olfactory dysfunction in the general population. Olfactory dysfunction is more common in patients with CRS with nasal polyposis (CRSwNP) compared to those without polyps.

PURPOSE

The present review aims to summarize the current literature on the mechanism behind olfactory dysfunction in CRSwNP and the impact of therapy on olfactory outcomes in this patient population.

METHODS

A comprehensive review of the available literature on olfaction in CRSwNP was performed. We evaluated the most recent evidence from studies on the mechanisms behind smell loss in CRSwNP and the impact of medical and surgical therapy for CRS on olfactory outcomes.

RESULTS

The mechanism behind olfactory dysfunction in CRSwNP is not completely understood, but evidence from clinical research and animal models suggests both an obstructive component causing conductive olfactory loss and an inflammatory response in the olfactory cleft leading to sensorineural olfactory loss. Oral steroids and endoscopic sinus surgery have both shown efficacy in improving olfactory outcomes in CRSwNP in the short term; however, the long-term response of these treatments remains uncertain. Newer targeted biologic therapies, such as dupilumab, have also shown remarkable and durable improvement in smell loss for CRSwNP patients.

CONCLUSION

Olfactory dysfunction is highly prevalent in the CRSwNP population. Although significant advances have been made in our understanding of olfactory dysfunction in the setting of CRS, additional studies are needed to elucidate cellular and molecular changes mediated by type 2-mediated inflammation in the olfactory epithelium with potential downstream effects on the central olfactory system. Further identification of these underlying basic mechanisms will be vital for developing future therapies targeted to improve olfactory dysfunction in patients with CRSwNP.

Molecular and Clinical Predictors of Quality of Life in Chronic Rhinosinusitis with Nasal Polyps

(1) Background: Factors influencing the quality of life (QoL) of patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) are poorly understood. We set out to determine the predictive factors on patients' QoL using the Sino-Nasal Outcome Test-22 (SNOT-22); (2) Methods: An ambispective analysis of data from patients diagnosed with CRSwNP in our institution. All the patients underwent a nasal polyp biopsy and completed the SNOT-22 questionnaire. Demographic and molecular data as well as the SNOT-22 scores were collected. Patients were classified in six subgroups considering the presence of asthma, non-steroidal drugs (NSAID) intolerance and corticosteroid resistance; (3) Results: The mean SNOT-22 score was 39. Considering the clinical parameters, the SNOT-22 value was significantly associated with NSAID intolerance (p = 0.04) and the endoscopic polyp score (p = 0.04). A high SNOT-22 value was also correlated with high tissue eosinophilia (p = 0.01) and high IL-8 expression; (4) Conclusions: Eosinophilia, IL-8 expression and NSAID intolerance can be used as predictors of worse QoL in patients with CRSwNP.

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.

The roles of eosinophils and interleukin-5 in the pathophysiology of chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is generally associated with eosinophilic tissue infiltration linked to type 2 inflammation and characterized by elevated levels of interleukin (IL)-5 and other type 2 inflammatory mediators. Although distinct and overlapping contributions of eosinophils and IL-5 to CRSwNP pathology are still being explored, they are both known to play an important role in NP inflammation. Eosinophils secrete numerous type 2 inflammatory mediators including granule proteins, enzymes, cytokines, chemokines, growth factors, lipids, and oxidative products. IL-5 is critical for the differentiation, migration, activation, and survival of eosinophils but is also implicated in the biological functions of mast cells, basophils, innate lymphoid cells, B cells, and epithelial cells. Results from clinical trials of therapeutics that target type 2 inflammatory mediators (including but not limited to anti-IL-5, anti-immunoglobulin-E, and anti-IL-4/13) may provide further evidence of how eosinophils and IL-5 contribute to CRSwNP. Finally, the association between eosinophilia/elevated IL-5 and greater rates of NP recurrence after endoscopic sinus surgery (ESS) suggests that these mediators may have utility as biomarkers of NP recurrence in diagnosing and assessing the severity of CRSwNP. This review provides an overview of eosinophil and IL-5 biology and explores the literature regarding the role of these mediators in CRSwNP pathogenesis and NP recurrence following ESS. Based on current published evidence, we suggest that although eosinophils play a key role in CRSwNP pathophysiology, IL-5, a cytokine that activates these cells, also represents a pertinent and effective treatment target in patients with CRSwNP.

Olfaction Recovery following Dupilumab Is Independent of Nasal Polyp Reduction in CRSwNP

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic type 2 inflammatory disease characterized by olfactory impairment (OI) as one of the most troublesome symptoms. Currently, biologics represent a new option in the treatment of uncontrolled type 2 CRSwNP. This is a retrospective real-life observational study involving adult patients affected by severe uncontrolled CRSwNP. At baseline, and 3 and 6 months after Dupilumab add on to intranasal steroids (INS), patients underwent the 22-item Sinonasal Outcome Test (SNOT-22), nasal endoscopy, Visual Analogue Scale (VAS) scale for OI, and Sniffin Sticks-16 items identification test (SS-I). We observed improvement in all clinical outcomes with a significant correlation between VAS-SS-I/SNOT22, whereas we did not find a correlation between Nasal Polyp Score (NPS) and SS-I or VAS. Interestingly, patients reported a higher degree of improvement of OI on the VAS than on the SS-I. These data demonstrate that the patients were not aware about the degree of their OI and the perception of general improvement in their health-related quality of life (HRQoL) may have influenced the VAS score. Moreover, we observed a lack of correlation between NPS and SS-I or VAS, suggesting that OI did not depend on the polyps’ volume and may be due mainly to the resolution of inflammation. So, the physiopathological mechanisms underlying OI in CRSwNP and its recovery after Dupilumab might be unrelated to the volume of the polyps and might depend mainly on the anti-inflammatory effects. Future studies including biomarkers may be useful to clarify this aspect.

International consensus statement on allergy and rhinology: Olfaction

BACKGROUND

The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O).

METHODS

Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus.

RESULTS

The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies.

CONCLUSION

This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.

Studies on Clinical Features, Mechanisms, and Management of Olfactory Dysfunction Secondary to Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is one of the most common causes of inflammation of the olfactory system, warranting investigation of the link between chronic inflammation and the loss of olfactory function. Type 2 inflammation is closely related to the clinical features and disease mechanisms of olfactory dysfunction secondary to CRS. Patients with eosinophilic CRS, aspirin-exacerbated respiratory disease, and central compartment atopic disease report increased olfactory dysfunction. Increased levels of interleukin-(IL-)2, IL-5, IL-6, IL-10, and IL-13 in the mucus from the olfactory slit have been reported to be associated with reduced olfactory test scores. The influence of several cytokines and signaling transduction pathways, including tumor necrosis factor-α, nuclear factor-κB, and c-Jun N-terminal kinases, on olfactory signal processing and neurogenesis has been demonstrated. Corticosteroids are the mainstay treatment for olfactory dysfunction secondary to CRS. Successful olfaction recovery was recently demonstrated in clinical trials of biotherapeutics, including omalizumab and dupilumab, although the treatment effect may diminish gradually after stopping the use of the medications. Future studies are required to relate the complex mechanisms underlying chronic inflammation in CRS to dysfunction of the olfactory system.

Local Allergic Inflammation in Chronic Rhinosinusitis With Nasal Polyps Could Influence on Disease Severity and Olfaction

Background and Objectives: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial disease resulting from inflammation of the nasal cavity and paranasal sinuses. Systemic allergic inflammation is an important cause of CRSwNP; however, the effect of local allergic inflammation is unclear. This study was designed to investigate the effect of local allergic inflammation in CRSwNP.Materials and Methods: The study included 11 patients with CRSwNP and 18 control subjects. Olfactory function was measured with the Korean Version of Sniffin’s stick test. Nasal lavage fluids (NLFs) were collected from all subjects and analyzed for total IgE, eosinophilic cationic protein (ECP), and cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-4, IL-10, IL-17A, interferon-γ). Flow cytometry was used to measure various inflammatory cells in the NAL fluids.Results: On analysis of flow cytometry and enzyme-linked immunosorbent assay, we found that CRSwNP patients had significantly increased eosinophil (%) and ECP levels in NLFs. In addition, there was significant local-systemic correlation between ECP level in NLFs and blood eosinophils (%) (r=0.391); however, there was no significant association between eosinophils (%) in NLFs and blood eosinophils. Moreover, in CRSwNP patients, the severity of disease was related with blood eosinophil (%), eosinophil (%), and ECP levels in NLFs, whereas olfactory function was associated with blood eosinophil (%) and ECP levels in NLFs.Conclusion: CRSwNP is a disease with high allergic inflammation that has negative impacts on the severity of disease and olfactory function. Therefore, we suggest that control of local allergic inflammation will be helpful to treat CRSwNP patients.

Predictive value of clinical characteristics in eosinophilic chronic rhinosinusitis with nasal polyps: A cross-sectional study in the Chinese population

BACKGROUND

Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is a refractory subtype of chronic rhinosinusitis with nasal polyps (CRSwNP), with clinical characteristics differing from those of non-ECRSwNP. We aimed to explore the predictive value of clinical characteristics, including medical history, symptoms, and signs, prior to ECRSwNP diagnosis, and to develop a nomogram for use in clinical practice.

METHODS

A total of 502 patients with CRSwNP were enrolled. Based on the degree of eosinophilic infiltration in nasal polyps (NPs), patients were classified as ECRSwNP or non-ECRSwNP group. Participants' demographic characteristics, asthma history, severity of nasal symptoms (nasal obstruction, rhinorrhea, hyposmia, and facial pain/headache) according to the visual analog scale, and nasal polyp scores based on polyp scoring system were recorded. Logistic regression analysis was performed to screen for independent risk factors, and a model nomogram was constructed.

RESULTS

The percentage of asthmatic patients and the hyposmia, rhinorrhea, and total nasal symptom scores were significantly higher in ECRSwNP patients than that in non-ECRSwNP patients. The nasal polyp score was lower in the eosinophilic group than that in the non-eosinophilic group. Logistic regression analysis revealed that asthma history and hyposmia, rhinorrhea and nasal polyp scores were independent predictors of ECRSwNP. A nomogram consisting of these four independent risk factors was constructed, and its C-index was 0.808 (95% CI, 0.771 to 0.846).

CONCLUSIONS

The nomogram based on asthma history and olfactory, rhinorrhea, and nasal polyp scores could help predict ECRSwNP, providing a simple, fast, and practical way to distinguish ECRSwNP from non-ECRSwNP cases in clinical practice.

Effects of Fluticasone Exhalation Delivery System in Patients With Chronic Rhinosinusitis With Nasal Polyps: A Systematic Review

BACKGROUND

Nasal sprays with corticosteroids deliver medication to the restricted areas including anterior and inferior parts of the nasal cavity. The fluticasone exhalation delivery system (EDS-FLU) has recently been proved to improve care by increasing superior/posterior intranasal corticosteroid deposition.

OBJECTIVE

This study aims to evaluate the efficacy of EDS-FLU in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODOLOGY

A systematic literature review using Pubmed, Embase, Cochrane Library, and Web of Science was conducted to identify studies assessing the effect of EDS-FLU on outcomes in patients with CRSwNP.

RESULTS

Of the initial 108 abstracts reviewed, 4 full-text articles were included. The 22-item sinonasal outcome test scores were significantly decreased in patients with CRSwNP after receiving EDS-FLU twice a day (93, 186, or 372 μg) for 16 weeks when compared with exhalation delivery system (EDS)-placebo (all P < .001). Patients with CRSwNP reported significant improvement of smell after receiving twice daily EDS-FLU twice a day (93, or 372 μg) for 4 weeks when compared with EDS-placebo (all P < .05). The proportions of patients achieving ≥1-point improvement in total polyp grade were significantly higher in EDS-FLU group and dose dependent, with the highest rates in the 372 μg group. The proportions of patients achieving polyp elimination were significantly higher in EDS-FLU group with the highest rates in the 372 μg group.

CONCLUSION

This is the first systematic review of the clinical outcomes in patients with CRSwNP treated with EDS-FLU. EDS-FLU produced significant improvements regarding the quality of life, smell, and endoscopic assessment of polyp grade.

Rethinking neutrophils and eosinophils in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) often is characterized by an eosinophilic inflammatory pattern, nowadays referred to as type 2 inflammation, although the mucosal inflammation is dominated by neutrophils in about a third of the patients. Neutrophils are typically predominant in 50% of patients with CRS without nasal polyps, but also are found to play a role in patients with severe type 2 CRS with nasal polyp disease. This review aims at summarizing the current understanding of the eosinophilic and neutrophilic inflammation in CRS pathophysiology, and provides a discussion of their reciprocal interactions and the clinical impact of the mixed presentation in patients with severe type 2 CRS with nasal polyps. A solid understanding of these interactions is of utmost importance when treating uncontrolled severe CRS with nasal polyps with biologicals that are preferentially directed toward type 2 inflammation. We here focus on recent findings on both eosinophilic and neutrophilic granulocytes, their subgroups and the activation status, and their interactions in CRS.

[The role of nasal nitric oxide in diagnosis and endotypes of chronic rhinosinusitis with nasal polyp]

Objective:To investigate the roles of nasal nitric oxide（nNO） in diagnosis and endotypes of CRSwNP. Methods:Eighty-two CRSwNP patients and thirty healthy volunteers were recruited for this study. The patients were classified into eosinophilic CRSwNP （Eos CRSwNP） and non-eosinophilic CRSwNP （non-Eos CRSwNP） endotypes by tissue eosinophil percentage. nNO levels were measured with an electrochemical sensor-based device. nNO levels and clinical factors were compared among the groups. Receiver-operating characteristic （ROC） curve and logistic regression analyses were performed to evaluate the predictive ability of the nNO for diagnosis and endotypes of CRSwNP. Results:Eos CRSwNP patients（143.9±106.2） ×10-9 had lower nNO levels than non-Eos CRSwNP[（228.3±109.2） ×10-9, P=0.000 9） and healthy subjects（366.5±88.0） ×10-9, P<0.000 1）. Patients with atopy exhibited significantly higher levers of nNO compared with patients without atopy（P<0.05）. For Eos CRSwNP diagnosis, nNO had the highest predictive value（AUC: 0.939; sensitivity: 76.74%; specificity: 96.67%; cut-off value: 231×10-9, P<0.001）. Furthermore, nNO levels were associated with CRSwNP endotypes（odds ratio: 1.010; 95% confidence interval: 1.003%, 1.016%; P=0.002）. When the nNO concentration was 158 ×10-9, we could discriminate Eos CRSwNP from non-Eos CRSwNP（AUC=0.710, sensitivity: 76.92%; specificity, 60.47%, P=0.001）. After it was combinated by nNO, periphera blood eosinophil count（PEAC） and VAS score, the AUC was increased to 0.894（95%CI=0.807 to 0.951, P<0.000 1, sensitivity: 76.74%, specificity: 89.74%）. Conclusion:nNO may has potential for non-invasive diagnosis and endotype of CRSwNP. nNO combined with PEAC and VAS score may be an ideal diagnostic tool for endotyps of Eos CRSwNP. However, the atopic status of the patients influenced the levels of nNO.

Olfactory cleft mucus inflammatory proteins in CRS: a case-control study

BACKGROUND

Multiple hypotheses are evolving that suggest several, potentially overlapping etiologies for olfactory dysfunction (OD) in chronic rhinosinusitis (CRS). Understanding inflammatory cytokine profiles of the olfactory cleft (OC) and their association with olfactory function is foundational for future clinical care and research.

METHODS

This cross-sectional, case-control study evaluates associations among OC mucus inflammatory proteins, psychophysical olfactory testing, and computed tomography (CT) analysis of the OC and sinuses. Normative reference intervals were determined for each protein and odds ratios (ORs) were used to compare proportions of altered expression between CRS without nasal polyposis (CRSsNP) and CRS without nasal polyposis (CRSwNP).

RESULTS

Case subjects with CRS (n = 151) and controls (n = 74) were evaluated. A majority of OC proteins tested were found within detectable ranges for cases and controls. The CRS cohort had significantly higher concentrations for 23 of 26 proteins. CRS cases with abnormal levels of C-C motif chemokine ligand 2 (CCL2), CCL3, interleukin 5 (IL5), IL10, and IL13 associated with greater olfactory deficits. The prevalence of elevated IL5 and IL13 in anosmic patients was 64.6% and 62.5%, respectively (p < 0.004). CRS cases with the highest odds of elevated expression in CRSwNP were IL5 (OR = 10.83) and IL13 (OR = 8.36). However, both IL5 and IL13 were still elevated in approximately 14% of CRSsNP patients. The highest magnitude of correlation between the total percent of OC opacification was found to be with IL5 (r = 0.543; p < 0.001), whereas other moderate correlations were noted with immunoglobulin E (IgE), IL10, and IL13.

CONCLUSION

This study confirmed that OC inflammatory proteins vary both by disease phenotype and in their association with OD. Type 2 inflammatory mediators are increased in CRS, especially within the CRSwNP group. However, a substantial proportion of CRSsNP also express type 2 inflammatory mediators. Further research is necessary to understand the complex roles OC mucous inflammatory proteins might play in defining endotype and in impacting CRS-related OD. ©2021 ARSAAOA, LLC.

Reversibility of mucociliary clearance and olfaction impairment following endoscopic sinus surgery: a prospective observational study

OBJECTIVE

Chronic rhinosinusitis is associated with altered mucociliary clearance and olfaction. The study aimed to analyse the reversibility of impairment and endoscopic factors predicting changes in mucociliary clearance and olfactory parameters.

METHODS

This prospective study included patients undergoing functional endoscopic sinus surgery for medically refractory chronic rhinosinusitis. Pre- and post-operative measurements of mucociliary clearance, olfactory thresholds, and identification scores were recorded.

RESULTS

Of the 96 patients, 65.6 per cent had polyposis and 80.2 per cent underwent primary surgery. Improvements in mucociliary clearance and olfaction scores were seen in all patients, with greater reversibility of impairment in patients with polyposis and in those who underwent revision surgery. The presence of polyps correlated significantly with changes in mucociliary clearance and olfaction.

CONCLUSION

The study highlights improvements in mucociliary clearance, olfactory thresholds and identification scores after functional endoscopic sinus surgery in chronic rhinosinusitis with or without nasal polyposis, as well as for primary and revision surgeries. Adequate post-operative care and prevention of polyps recurrence help to improve mucociliary clearance and olfaction scores.

Biology and Function of Eosinophils in Chronic Rhinosinusitis With or Without Nasal Polyps

Chronic rhinosinusitis (CRS) with or without nasal polyposis is a complex medical condition characterized by varying patterns of chronic innate and adaptive mucosal inflammation. Treatment of CRS has been traditionally limited to corticosteroids and sinus surgery; however, novel biologics have more recently been evaluated as steroid- and surgery-sparing options. While it is clear that there are different subtypes or endotypes of CRS, perhaps the most frequent presentation involves the features of type 2 inflammation, including a prominent tissue eosinophilia component. The purpose of this review is to provide an update on eosinophil biology as well as on the potential contribution of eosinophils and their mediators to the pathophysiology of CRS, drawing mechanistic conclusions mainly from studies of human sinus mucosal tissues, nasal secretions, and benefits (or lack thereof) from the use of various pharmacotherapies. The unavoidable conclusion derived from this approach is that eosinophils themselves cannot fully explain the underlying pathophysiology of this complex disorder.

Evaluation of olfactory dysfunction to estimate the presence of eosinophilic chronic rhinosinusitis in patients with asthma

BACKGROUND

Eosinophilic chronic rhinosinusitis (ECRS) is often complicated by asthma and can be difficult to diagnose. This study aimed to clarify the usefulness of the self-administered odor questionnaire (SAOQ) and visual analog scale (VAS) to identify olfactory disorders in patients with asthma.

METHODS

This retrospective study was conducted on patients with asthma who were referred to the Otolaryngology clinic between May and September 2018. The treatment step of asthma, asthma control test (ACT), pulmonary function test, peripheral blood eosinophils, and fractional exhaled nitric oxide (FeNO) were analyzed. ECRS was diagnosed based on the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis Study score. Olfactory dysfunction was evaluated using the SAOQ and VAS for olfactory disorders.

RESULTS

The study included 56 patients (18 males and 38 females), who were divided into two groups; those with ECRS (n = 18) and those without ECRS (n = 38). Age, sex, treatment step, ACT score, and pulmonary function were not significantly different between the groups. The ECRS group had a significantly higher FeNO value (89.1 ppb vs. 39.1 ppb) and a significantly lower SAOQ score (40.1% vs. 96.1%). The area under the receiver operating characteristic curve for the efficacy of ECRS diagnosis was 0.88, 0.889, 0.799, and 0.757 for SAOQ, VAS, blood eosinophil count, and FeNO, respectively.

CONCLUSION

The SAOQ and VAS scores were useful tools that presented similar results to the blood eosinophil count and FeNO, and may help to improve the diagnosis of ECRS in patients with asthma.

The roles of nasal nitric oxide in diagnosis and endotypes of chronic rhinosinusitis with nasal polyps

Background

Chronic rhinosinusitis with polyps (CRSwNP) is a global health concern. Nasal nitric oxide (nNO), a clinical biomarker, have been studied to assess the presence of airway mucosal inflammation. This study aimed to clarify the roles of nNO in diagnosis and endotypes of CRSwNP.

Methods

Eighty-two CRSwNP patients and thirty healthy volunteers were recruited for this study. The patients were classified into eosinophilic CRSwNP (Eos CRSwNP) and non⁃eosinophilic CRSwNP (Non-Eos CRSwNP) endotypes by tissue eosinophil percentage. nNO levels were measured with an electrochemical sensor-based device. nNO levels and clinical factors were compared among the groups. Receiver-operating characteristic (ROC) curve and logistic regression analyses were performed to evaluate the predictive ability of the nNO for diagnosis and endotypes of CRSwNP.

Results

Eos CRSwNP patients(143.9 ± 106.2, ppb) had lower nNO levels than Non-Eos CRSwNP(228.3 ± 109.2, ppb, p = 0.013) and healthy subjects(366.5 ± 88, ppb, p < 0.0001). Patients with atopy exhibited significantly higher levers of nNO compared with patients without atopy (p < 0.05). For Eos CRSwNP diagnosis, nNO had high predictive value for Eos CRSwNP (AUC: 0.939; sensitivity: 76.74%; specificity: 96.67%; cut-off value: 231 ppb, p < 0.001). Furthermore, nNO levels were associated with CRSwNP endotypes (odds ratio: 1.010; 95% confidence interval: 1.003, 1.016%; p = 0.002). When the nNO concentration was 158 ppb, we could discriminate Eos CRSwNP from Non-Eos CRSwNP (AUC = 0.710, sensitivity: 76.92%; specificity, 60.47%, P = 0.001). After it was combinated by nNO, peripheral blood eosinophil count (PEAC) and VAS score, the AUC was increased to 0.894 (95%CI = 0.807 to 0.951, p < 0.0001, sensitivity:76.74%, specificity: 89.74%).

Conclusions

nNO may have potential for non-invasive diagnosis and endotype of CRSwNP. nNO combined with PEAC and VAS score may be a good diagnostic tool for endotyps of Eos CRSwNP. However, the atopic status of the patients influenced the levels of nNO.

Predictive and Diagnostic Value of Nasal Nitric Oxide in Eosinophilic Chronic Rhinosinusitis with Nasal Polyps

BACKGROUND

A hallmark of eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP) is mucosal eosinophil-predominant inflammation. Nasal nitric oxide (nNO) is a known biomarker of eosinophilic inflammation in the upper airway. However, the utility of nNO measurement in the upper airway remains controversial. The present study aimed to compare the use of other clinical parameters with nNO to prediagnose patients with eCRSwNP from Central China.

METHODS

From June 2019 to December 2019, 70 patients with CRSwNP undergoing endoscopic sinus surgery and 30 healthy subjects were enrolled. nNO measurements were performed in all of these subjects. Computed tomography scans, full blood count with differential analysis, and determination of total immunoglobulin E (total IgE) and plasma cytokines were performed before surgery. Receiver operating characteristic curves and logistic regression analysis were used to assess the predictive potential of the clinical parameters.

RESULTS

We recruited 24 patients with eCRSwNP and 46 with noneosinophilic CRSwNP (non-eCRSwNP). In patients with eCRSwNP, nNO levels were significantly higher than those in patients with non-eCRSwNP (p < 0.0001). Blood eosinophil percentages and counts, total IgE, and CT-derived ethmoid sinus and maxillary sinus ratio (E/M ratio) were all significantly higher compared with those in patients with non-eCRSwNP (p < 0.05). To diagnose eCRSwNP, the highest area under the curve (0.803) was determined for nNO. At a cutoff of >329 parts per billion (ppb), the sensitivity was 83.30% and the specificity was 71.70%. However, the levels of plasma cytokines Th1/Th2 were not significantly different between the histological types of CRSwNP (p > 0.05).

CONCLUSION

Measurement of nNO is useful for the early diagnosis of eCRSwNP.

Efficacy of Benralizumab in severe asthma in real life and focus on nasal polyposis

INTRODUCTION

Severe asthma occurs in 5-10% of asthmatic patients, with nasal polyposis as one of the most frequent comorbidity. Benralizumab was recently marketed, thus we could analyse its effects in real-life in severe asthma, and compare the effects of the drug in patients with and without polyposis.

METHODS

Patients with severe asthma, receiving Benralizumab were enrolled in Italian asthma centres. The efficacy criteria for asthma (exacerbation rate, oral corticosteroid intake, hospitalizations, pulmonary function, exhaled nitric oxide) were evaluated at baseline and after 24 weeks of treatment. Patients were then sub-analysed according to the presence/absence of nasal polyposis.

RESULTS

Fifty-nine patients with severe uncontrolled asthma (21 males, age range 32-78) and treated with benralizumab for at least 24 weeks has been evaluated, showing significant improvements in asthma-related outcomes, except for pulmonary function and exhaled nitric oxide. This included a reduction in the sino-nasal outcome-22 score versus baseline of 13.7 points (p = .0037) in the 34 patients with nasal polyposis. Anosmia disappeared in 31% patients (p = .0034). When comparing the groups with and without nasal polyposis, a similar reduction of exacerbations was seen, with a greater reduction of the steroid dependence in patients with polyposis (-72% vs -53%; p < .0001), whereas lung function was significantly more improved (12% vs 34%, p = .0064) without polyposis patients.

CONCLUSIONS

Benralizumab, after 6 months of treatment, confirmed its efficacy in severe asthma, and also in nasal polyposis, which is the most frequent comorbidity. The efficacy of Benralizumab in reducing steroid dependence was even higher in patients with polyposis.

Comparison of olfactory and taste functions between eosinophilic and non-eosinophilic chronic rhinosinusitis

OBJECTIVE

Most patients with chronic rhinosinusitis (CRS) complain of olfactory and/or taste dysfunctions. However, olfactory and taste dysfunctions depending on the subtype of CRS, classified as eosinophilic CRS (ECRS) and non-eosinophilic CRS (NCRS), have not been clearly reported. Therefore, the purpose of this study was to investigate the clinical features in olfactory and taste functions according to the subtype classified as ECRS and NCRS.

METHODS

We retrospectively analyzed the electronic medical records of patients who underwent endoscopic sinus surgery and were diagnosed with CRS. The patients were divided into ECRS and NCRS groups, according to their Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) scores. We analyzed demographic characteristics, Sino-Nasal Outcome Test findings, Lund-Mackay score, and the results of previously-validated tests, including the Korean Version of Sniffin' Stick test and chemical gustatory function test.

RESULTS

Patients with ECRS and NCRS had decreased olfactory and taste functions compared to the control group. In particular, the olfactory score of ECRS patients was lower than that of NCRS patients (18.1 ± 9.5 vs 23.7 ± 8.5, respectively, p <0.001). On the other hand, taste scores of ECRS patients were not statistically different compared to NCRS patients (19.1 ± 4.7 vs. 18.3 ± 4.7, respectively, p = 0.166). Olfactory score decreased with increase in JESREC score (r=-0.203, p = 0.002), but it had no correlation with taste score (r = 0.072, p = 0.276).

CONCLUSION

We found a difference in olfactory function but no difference in taste function between patients in ECRS and NCRS groups. These results may provide valuable clinical features in terms of olfactory and taste functions according to the subtypes of CRS.

Superior turbinate eosinophilia predicts olfactory decline in patients with chronic rhinosinusitis

BACKGROUND

Predicting postoperative olfactory decline in patients with chronic rhinosinusitis (CRS) remains a considerable challenge.

OBJECTIVE

To evaluate patterns of postoperative olfactory function in patients with CRS and explore potential predictors of postoperative olfactory decline.

METHODS

A total of 76 patients with CRS electing endoscopic sinus surgery (ESS) were enrolled in this prospective study. Olfaction was assessed with Sniffin' Sticks preoperatively and 3 months postoperatively. Preoperative peripheral venous blood and superior turbinate at surgery were collected for eosinophil quantification. Olfactory cleft was evaluated by computed tomography and endoscopy. Postoperative olfactory decline was defined by a decrease in threshold-discrimination-identification (TDI) score more than 0 point. Multivariable logistic regression analysis was conducted to identify potential predictors associated with postoperative olfactory decline in TDI score.

RESULTS

A total of 30.26% of patients with CRS (23/76) presented with olfactory decline 3 months post-ESS. Patients with CRS with olfactory decline showed significantly higher preoperative tissue eosinophils (P < .001), blood eosinophil count (P = .002), blood eosinophil percentage (P = .009), and preoperative TDI scores (P = .017) than patients with CRS without olfactory decline. After adjusting for patient demographics and comorbidities, the preoperative tissue eosinophilia was significantly associated with patients with CRS with postoperative olfactory decline (odds ratio = 1.103; P = .038). An absolute count of 23.5 eosinophils per high-power field in superior turbinate was the best predictor of olfactory decline with the highest area under the receiver operating characteristic curve of 0.901.

CONCLUSION

Superior turbinate eosinophilia is highly associated with olfactory decline in patients with CRS 3 months after ESS.

Application of Clinical Scores in the Differential Diagnosis of Chronic Rhinosinusitis With Nasal Polyps in a Chinese Population

Background

Eosinophilic (Eos) and non-eosinophilic (non-Eos) chronic rhinosinusitis with nasal polyps (CRSwNP) react differently to clinical treatment, with eosinophilic chronic rhinosinusitis with nasal polyps (Eos CRSwNP) being more likely to recur after surgery.

Objective

To explore the clinical value of the visual analog scale (VAS), nasal endoscopy score (Lund–Kennedy, L–K), computed tomography (CT) score (Lund–Mackay scoring system, L–M), and blood Eos percentage in the differential diagnosis of Eos CRSwNP and non-Eos CRSwNP.

Methods

Ninety-nine patients with CRSwNP were enrolled in this study and assigned to 2 groups (Eos CRSwNP and non-Eos CRSwNP). The blood Eos percentage and VAS, L–K, and L–M scores in the 2 groups of patients were compared. A receiver operating characteristic (ROC) was used to assess the usefulness of VAS, L–K, and L–M scores for differentiating Eos CRSwNP and non-Eos CRSwNP.

Results

There were significantly differences between the Eos CRSwNP group and non-Eos CRSwNP group in the following scores: blood Eos percentage, mean VAS score, olfaction/VAS, general discomfort/L–K, edema score/L–K, olfactory cleft (OC) score via endoscopy, mean L–M score, anteriorethmoid sinus score, posterior ethmoid sinus score, sphenoid sinus score, frontal sinus score, and OC score via CT. An ROC analysis showed that blood Eos percentage had the highest area under the ROC curve (AUC) value (0.749); however, several other scores (olfaction score/VAS, edema score/L–K, and mean L–M score) also had high AUC values. The combination of olfaction score/VAS and blood Eos percentage had the highest clinical convenience score as well as high sensitivity and specificity. A combination of cutoff values for the 2 predictors (blood Eos percentage ≥3.85%, olfaction score/VAS score ≥3) showed a sensitivity of 75.5% and a specificity of 78.0%.

Conclusion

The olfaction score/VAS score and the blood Eos percentage can be combined to differentiate Eos CRSwNP from non-Eos CRSwNP in a Chinese population.

Correlation of mucus inflammatory proteins and olfaction in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is one of the most common causes of olfactory loss, but the pathophysiology underlying olfactory dysfunction in CRS has not been fully elucidated. Previous studies found correlations between olfactory cleft (OC) inflammatory cytokines/chemokines and olfaction in CRS. The purpose of this study was to evaluate the relationship between OC mucus inflammatory proteins and olfaction in a multi-institutional cohort.

METHODS

Adults with CRS were prospectively recruited. Demographics, comorbidities, olfactory assessment (Sniffin' Sticks), computed tomography (CT), and OC mucus for protein analysis were collected. Statistical analysis was performed to determine associations between olfactory function, OC mucus protein concentrations, and CT opacification.

RESULTS

Sixty-two patients were enrolled in the study, with an average age of 48.2 (standard deviation, 16.2) years, and 56.5% were female and 59.7% were classified as CRS with nasal polyps (CRSwNP). Ten of 26 OC mucus proteins were significantly correlated with threshold, discrimination, and identification (TDI) scores and OC opacification. Subgroup analysis by polyp status revealed that, within the CRSwNP group, C-C motif ligand 2 (CCL2), interleukin-5 (IL-5), IL-6, IL-13, IL-10, IL-9, tumor necrosis factor-α (TNF-α), CCL5, and CCL11 were significantly correlated with olfaction. For CRS without nasal polyps (CRSsNP), only C-X-C ligand 5 (CXCL5) showed a correlation. In CRSwNP, IL-6, IL-10, vascular endothelial growth factor-A, and immunoglobulin E (IgE) correlated with OC opacification, whereas, in CRSsNP, only CXCL5 showed a correlation. OC mucus proteins and Lund-Mackay score correlated only in the CRSsNP group (CXCL5, IL-5, IL-13, IgE).

CONCLUSION

Several OC mucus proteins have been found to correlate with olfactory function and OC opacification. The profile of OC mucus proteins differs between CRSsNP and CRSwNP subgroups, suggesting different mechanisms between groups, but further study is required.

Postoperative evaluation of olfactory dysfunction in eosinophilic chronic rhinosinusitis - comparison of histopathological and clinical findings

Background: Olfactory dysfunction in eosinophilic chronic rhinosinusitis (ECRS) is poorly understood. Objective: To compare olfactory mucosal injury due to eosinophil infiltration in ECRS with postoperative olfactory function. Methods: Seventeen ECRS patients (ECRS group) and 18 bilateral rhinosinusitis (non-ECRS group) patients were compared. At 3 and 12 months post-endoscopic sinus surgery (ESS), all patients were evaluated for subjective symptoms (nasal obstruction, nasal discharge and olfactory dysfunction), endoscopic nasal findings, CT score and T&T olfactometer recognition threshold test. The eosinophil count, OMP-positive cells and epithelial erosion in olfactory mucosa collected during ESS were compared with the postoperative olfactory function. Results: The non-ECRS group showed significant improvement in all clinical findings at 3 and 12 months, but the ECRS group showed worsening of the olfactory dysfunction symptoms and T&T olfactometer recognition threshold at 12 months because of recurrence of sinusitis. The groups differed significantly in the ΔT&T value (i.e. pre-ESS T&T recognition threshold - post-ESS T&T recognition threshold) at both 3 and 12 months, and the degree of olfactory improvement differed. Histologically, the ECRS group showed significantly more eosinophils, fewer OMP-positive cells and greater epithelial erosion than the non-ECRS group. Conclusions: Eosinophilic inflammation was thought to cause olfactory mucosal injury/dysfunction.

Olfactory cleft mucus proteins associated with olfactory dysfunction in a cohort without chronic rhinosinusitis

BACKGROUND

Olfactory dysfunction (OD) is a common problem, affecting up to 20% of the general population. Previous studies identified olfactory cleft mucus proteins associated with OD in chronic rhinosinusitis (CRS) but not in a healthy population. In this study we aimed to identify olfactory cleft mucus proteins associated with olfaction in individuals without sinus disease.

METHODS

Subjects free of sinus disease completed medical history questionnaires that collected data regarding demographics, comorbidities, and past exposures. Olfactory testing was performed using Sniffin' Sticks, evaluating threshold, discrimination, and identification. Olfactory cleft mucus (OC) and, in select cases, inferior turbinate mucus (IT) were collected with Leukosorb paper and assays performed for 17 proteins, including growth factors, cytokines/chemokines, cell-cycle regulators, and odorant-binding protein (OBP).

RESULTS

Fifty-six subjects were enrolled in the study, with an average age of 47.8 (standard deviation [SD], 17.6) years, including 33 females (58.9%). The average threshold/discrimination/identification (TDI) score was 30.3 (SD, 6.4). In localization studies, OBP concentrations were significantly higher in OC than IT mucus (p = 0.006). Cyclin-dependent kinase inhibitor 2A (CDKN2A/p16INK4a), basic fibroblast growth factor (bFGF), chemokine ligand 2 (CCL2/MCP-1), granulocyte macrophage colony-stimulating factor (GM-CSF), and chemokine ligand 20 (CCL20/MIP-3a) all inversely correlated with overall TDI (all rho ≥ -0.479, p ≤ 0.004). Stem cell factor (SCF) correlated positively with overall TDI (rho = 0.510, p = 0.002).

CONCLUSION

Placement of Leukosorb paper is relatively site-specific for olfactory proteins and it is feasible to collect a variety of olfactory cleft proteins that correlate with olfactory function. Further study is required to determine mechanisms of OD in non-CRS subjects.

Contribution of Epithelial Cell Dysfunction to the Pathogenesis of Chronic Rhinosinusitis with Nasal Polyps

Background

In the past, the airway epithelium was thought to be primarily an inert physical barrier. We now know that the upper airway epithelium plays a critical role in both innate and adaptive immunity, and that epithelial dysfunction is strongly associated with inflammatory airway disease. The pathogenesis of chronic rhinosinusitis is poorly understood, but growing evidence supports a key role for the airway epithelium in the pathophysiology of the disease.

Objective

The purpose of this study is to explore our current understanding of how dysfunction in human sinonasal epithelial cells (HSNECs) contributes to the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and to examine how current and developing therapies affect epithelial cell functions.

Methods

A literature review of papers published in English pertaining to epithelial cell dysfunction in patients with CRSwNP was performed using the PubMed database. The search utilized combinations of the following key words: sinusitis, polyps, epithelium, pathophysiology, barrier function, dendritic cells, eosinophils, T cells, complement, mucociliary clearance, vitamin D, cytokines, chemokines, taste receptors, steroids, saline, and therapy.

Results

HSNEC mucociliary clearance, barrier function, secretion of cytokines, influence on dendritic cells, influence on T-cells, regulation of eosinophils, vitamin D metabolism, complement production, and taste receptor function are altered in patients with CRSwNP and contribute to the pathogenesis of the disease. Current therapies utilized to manage CRSwNP counteract the effects of HSNEC dysfunction and relieve key symptoms of the disease.

Conclusion

HSNECs are key players in both innate and adaptive immunity, and altered epithelial functions are closely intertwined with the pathogenesis of CRSwNP. Our review supports further investigation of altered HSNEC function in patients with CRSwNP and supports development of novel epithelial-targeted therapies for its management.

Predictive Significance of Charcot–Leyden Crystals for Eosinophilic Chronic Rhinosinusitis With Nasal Polyps

Background

Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is a distinct phenotype of chronic rhinosinusitis with nasal polyps (CRSwNP), with many significantly different clinical features from non-eosinophilic chronic rhinosinusitis with nasal polyps (non-ECRSwNP). Thus, identification of subtypes is crucial for precise treatment. Immunohistology is a reliable way to present the subtypes; however, the results mainly depend on the observation of pathologist, and the method with automatic readout and the corresponding biomarkers is lacking.

Objective

The purpose of our research was to explore the predictive value of quantitative reverse transcription polymerase chain reaction (qRT-PCR) as an alternative method and messenger RNA (mRNA) expression of Charcot–Leyden crystals (CLC) as a corresponding target for ECRSwNP, which may benefit the automatized judgment.

Method

CLC mRNA levels in tissue samples from 48 CRSwNP patients and 10 controls were evaluated by quantitative real-time PCR. Hematoxylin and eosin staining was performed for histological assessment of CRSwNP and subtyping as ECRSwNP and non-ECRSwNP. Factors associated with ECRSwNP were determined with logistic regression analysis, the predictive value was presented by a receiver operating characteristic (ROC) curve, and optimal cutoff points of the predictors were identified as the Youden index.

Results

mRNA level of CLC in ECRSwNP was significantly elevated compared to either non-ECRSwNP group or control group, with no significant difference between non-ECRSwNP patients and controls. CLC mRNA levels were positively correlated with percentages of tissue eosinophil and peripheral blood eosinophil ( P < .001, r = .683; P = .003, r = .420, respectively). Logistic regression analysis revealed CLC mRNA level and blood eosinophil percentages were prediagnosis factors ( P = .007, P = .045, respectively) for ECRSwNP. ROC curves analysis indicated the area under the curve (AUC) of CLC mRNA level was 0.948 which was superior to the blood eosinophil percentage (AUC = 0.797; P = .044) as an optimal biomarker to predict ECRSwNP.

Conclusions

CLC mRNA levels based on the qRT-PCR may serve as a reliable and alternative method for the identification of ECRSwNP.

Eosinophil extracellular trap formation is closely associated with disease severity in chronic rhinosinusitis regardless of nasal polyp status

Chronic rhinosinusitis (CRS) is a heterogeneous inflammatory airway disease involving non-eosinophilic and eosinophilic phenotypes, which translate to various endotypes. Activated eosinophils and neutrophils are known to generate extracellular traps consisting of DNA and cytotoxic granule proteins. We sought to investigate the presence of eosinophil and neutrophil extracellular traps (EETs and NETs, respectively) in human CRS tissues and to clarify the associations with their clinical features. Nasal polyp (NP) or ethmoid tissue slides of 43 subjects from endoscopic sinus surgery for CRS were analysed. Quantitative analysis of EETs and NETs was performed by confocal microscopy using immunofluorescent staining. For correlation study, the presence of NPs, number of infiltrating tissue eosinophils, preoperative Lund–Mackay scores, and other comorbidities were analysed. EET formation was observed to varying degrees in all CRS groups and was correlated with the number of tissue eosinophils (r  =  0.83, p  < 0.001) regardless of the presence of NPs. Patients with more EETs demonstrated higher Lund–Mackay scores (r  =  0.51, p  = 0.009), blood eosinophilia (r  =  0.80, p  < 0.001), and decreased olfactory function (r  = −0.65, p  < 0.001). No correlation between the extent of EET formation and the presence of atopy or asthma was apparent. However, none of the CRS groups containing neutrophils formed NETs in this study. Eosinophilic CRS indicates the presence of EETs. Formation of EETs could have a role in clinical decision-making and prediction of treatment outcome of CRS, regardless of NP status.

Chronic rhinosinusitis in elderly patients is associated with an exaggerated neutrophilic proinflammatory response to pathogenic bacteria

BACKGROUND

Potential effects of aging on chronic rhinosinusitis (CRS) pathophysiology have not been well defined but might have important ramifications given a rapidly aging US and world population.

OBJECTIVE

The goal of the current study was to determine whether advanced age is associated with specific inflammatory CRS endotypes or immune signatures.

METHODS

Levels of 17 mucus cytokines and inflammatory mediators were measured in 147 patients with CRS. Hierarchical cluster analysis was used to identify and characterize inflammatory CRS endotypes, as well as to determine whether age was associated with specific immune signatures.

RESULTS

A CRS endotype with a proinflammatory neutrophilic immune signature was enriched in older patients. In the overall cohort patients 60 years and older had increased mucus levels of IL-1β, IL-6, IL-8, and TNF-α when compared with their younger counterparts. Increases in levels of proinflammatory cytokines were associated with both tissue neutrophilia and symptomatic bacterial infection/colonization in aged patients.

CONCLUSIONS

Aged patients with CRS have a unique inflammatory signature that corresponds to a neutrophilic proinflammatory response. Neutrophil-driven inflammation in aged patients with CRS might be less likely to respond to corticosteroids and might be closely linked to chronic microbial infection or colonization.

Automated classification of osteomeatal complex inflammation on computed tomography using convolutional neural networks

BACKGROUND

Convolutional neural networks (CNNs) are advanced artificial intelligence algorithms well suited to image classification tasks with variable features. These have been used to great effect in various real-world applications including handwriting recognition, face detection, image search, and fraud prevention. We sought to retrain a robust CNN with coronal computed tomography (CT) images to classify osteomeatal complex (OMC) occlusion and assess the performance of this technology with rhinologic data.

METHODS

The Google Inception-V3 CNN trained with 1.28 million images was used as the base model. Preoperative coronal sections through the OMC were obtained from 239 patients enrolled in 2 prospective chronic rhinosinusitis (CRS) outcomes studies, labeled according to OMC status, and mirrored to obtain a set of 956 images. Using this data, the classification layer of Inception-V3 was retrained in Python using a transfer learning method to adapt the CNN to the task of interpreting sinonasal CT images.

RESULTS

The retrained neural network achieved 85% classification accuracy for OMC occlusion, with a 95% confidence interval for algorithm accuracy of 78% to 92%. Receiver operating characteristic (ROC) curve analysis on the test set confirmed good classification ability of the CNN with an area under the ROC curve (AUC) of 0.87, significantly different than both random guessing and a dominant classifier that predicts the most common class (p < 0.0001).

CONCLUSION

Current state-of-the-art CNNs may be able to learn clinically relevant information from 2-dimensional sinonasal CT images with minimal supervision. Future work will extend this approach to 3-dimensional images in order to further refine this technology for possible clinical applications.

Treatments for smell and taste disorders: A critical review

A key concern of both the patient and physician is whether treatment is available that will eliminate or quell a given chemosensory disturbance. In cases where obvious oral, nasal, or intracranial pathology is involved, rational straightforward approaches to treatment are often available. In cases where damage to the sensory pathways is secondary to chronic inflammatory disease, trauma, viral invasion, toxic exposure, or unknown causes, the direction for therapy is more challenging. Indeed, many chemosensory disorders, if present for any period of time, cannot be reversed, while others spontaneously remit without any therapeutic intervention. This review assesses the strengths and weaknesses of more than two dozen approaches to treatment that have been suggested for a wide range of taste and smell disorders.

Patterns of olfactory dysfunction in chronic rhinosinusitis identified by hierarchical cluster analysis and machine learning algorithms

BACKGROUND

Olfactory dysfunction is a common symptom of chronic rhinosinusitis (CRS). We previously identified several cytokines potentially linked to smell loss, potentially supporting an inflammatory etiology for CRS-associated olfactory dysfunction. In the current study we sought to validate patterns of olfactory dysfunction in CRS using hierarchical cluster analysis, machine learning algorithms, and multivariate regression.

METHODS

CRS patients undergoing functional endoscopic sinus surgery were administered the Smell Identification Test (SIT) preoperatively. Mucus was collected from the middle meatus using an absorbent polyurethane sponge and 17 inflammatory mediators were assessed using a multiplexed flow-cytometric bead assay. Hierarchical cluster analysis was performed to characterize inflammatory patterns and their association with SIT scores. The random forest approach was used to identify cytokines predictive of olfactory function.

RESULTS

One hundred ten patients were enrolled in the study. Hierarchical cluster analysis identified 5 distinct CRS clusters with statistically significant differences in SIT scores observed between individual clusters (p < 0.001). A majority of anosmic patients were found in a single cluster, which was additionally characterized by nasal polyposis (100%) and a high incidence of allergic fungal rhinosinusitis (50%) and aspirin-exacerbated respiratory disease (AERD) (33%). A random forest approach identified a strong association between olfaction and the cytokines interleukin (IL)-5 and IL-13. Multivariate modeling identified AERD, computed tomography (CT) score, and IL-2 as the variables most predictive of olfactory function.

CONCLUSION

Olfactory dysfunction is associated with specific CRS endotypes characterized by severe nasal polyposis, tissue eosinophilia, and AERD. Mucus IL-2 levels, CT score, and AERD were independently associated with smell loss.

Effect of Cellulose Powder on Human Nasal Epithelial Cell Activity and Ciliary Beat Frequency

BACKGROUND

Cellulose powder (CP) has been reported as a safe and effective complementary treatment for allergic rhinitis (AR). Currently, CP has gained increasing application for clinical management worldwide, particularly in China. However, studies focusing on the effect of CP on normal human nasal epithelial cells (hNECs) and ciliary function are lacking. Here, we aimed to explore the adverse effects of CP on the activity and ciliary function of hNECs.

METHODS

We biopsied ethmoid sinus or middle turbinate tissues during surgical resection from control subjects who underwent endoscopic sinus surgery for diseases other than AR. Cells were isolated and passaged, followed by differentiation in an air-liquid interface (ALI). Flow cytometry and cell viability test (cell counting kit-8) were performed to detect the cytotoxicity of CP (effects on cell proliferation) on normal hNECs. By using the ALI culture model, we investigated the effects of CP on ciliary beat frequency (CBF).

RESULTS

There was a significant reduction in hNEC count at high concentrations of CP (2.5 mg/mL) at days 3 and 7 (both p < 0.05). As the concentration increased, cell death increased progressively from day 3 to day 7. However, these effects were not evident at low concentrations (0.25 mg/mL, p > 0.05). High-dose CP (2.5 mg) significantly reduced the CBF (p < 0.05). At lower concentrations (0.25-2.5 mg/mL), CP initially increased but subsequently reduced the CBF of hNECs compared with control group.

CONCLUSIONS

Cytotoxicity and the suppression of ciliary beat at high concentrations justify more prudent use of CP for the management of AR.

Olfactory and middle meatal cytokine levels correlate with olfactory function in chronic rhinosinusitis

OBJECTIVES/HYPOTHESIS

The etiology of chronic rhinosinusitis (CRS)-associated olfactory loss is unclear, but may result from inflammatory changes in the olfactory epithelium that result in signaling dysfunction or loss of olfactory neurons. Several proinflammatory cytokines have been associated with CRS, but their expression within the olfactory cleft microenvironment and association with olfactory function is unknown.

STUDY DESIGN

Prospective case-control study.

METHODS

Mucus was collected from the olfactory cleft and middle meatus of 31 CRS without nasal polyps subjects, 36 CRS with nasal polyps (CRSwNP) subjects, and 12 healthy controls. Olfactory function was assessed using the validated Smell Identification Test (SIT). Site-specific levels of 14 cytokines/chemokines (interleukin [IL]-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17A, tumor necrosis factor-α, Eotaxin, RANTES [regulated on activation, normal T cell expressed and secreted]) were assessed using a multiplex flow cytometric bead assay and correlated with SIT scores.

RESULTS

Mucus cytokine levels in the olfactory cleft were strongly or moderately correlated with levels in the middle meatus for all but one measured inflammatory mediators. SIT scores were inversely correlated with levels of IL-2 (P = .006), IL-5 (P < .0001), IL-6 (P = .0009), IL-10 (P < .0001), and IL-13 (P < .0001), with significance largely driven by CRSwNP patients.

CONCLUSIONS

The inflammatory microenvironment within the olfactory cleft mirrors that within the middle meatus. Elevated levels of IL-2, IL-5, IL-6, IL-10, and IL-13 in olfactory cleft mucus are associated with reduced olfactory identification scores in CRS patients. Altered levels of select olfactory mucus cytokines could potentially have deleterious effects on olfactory neuron function and turnover.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E304-E310, 2018.

The role of frontal sinus drillouts in nasal polyposis

PURPOSE OF REVIEW

Historically, the common frontal sinusotomy has been reserved only for salvage frontal sinus surgery in patients with severely recalcitrant inflammatory sinus disease. By understanding the pathophysiology of inflammatory sinus disease and the long-term role of topical medication in their treatment, the indications for Draf3 have expanded.

RECENT FINDINGS

A major therapeutic impact from endoscopic sinus surgery for inflammatory sinus disease is imparted by allowing sinus access to topical therapies to work. Although traditionally, the Draf3 frontal sinus procedure has been reserved for revision surgery in severe cases, advancements in technology, instrumentation, and techniques has allowed the Draf3 to evolve to efficient and safe procedure, often applied primarily in select patients. There is evidence to support the indication for Draf3 in primary surgery for severe cases.

SUMMARY

In inflammatory sinus disease, the goal of endoscopic sinus surgery is to convert the complex and limited frontal sinus outflow tracts into a simple common cavity. This allows for local, topical anti-inflammatory treatments to control the disease. When patients have broader inflammatory airway disease and asthma, the Draf3, as part of a neo-sinus cavity, is commonly applied early in surgical care.

Mucus T helper 2 biomarkers predict chronic rhinosinusitis disease severity and prior surgical intervention

BACKGROUND

Chronic rhinosinusitis (CRS) is a diverse clinical syndrome with a heterogeneous pathophysiology. Early attempts to identify CRS endotypes and biomarkers have largely relied on analysis of surgically obtained tissue, thus limiting their practical utility. This study examined the ability of mucus T helper 2 (Th2) biomarkers to predict CRS disease severity and clinical characteristics.

METHODS

CRS (n = 90) and healthy control subjects (n = 17) were prospectively enrolled prior to surgical intervention and mucus levels of interleukin (IL)-4, IL-5, and IL-13 were determined using a multiplex cytometric bead assay. Data for relevant cytokines was then scaled, normalized, and later combined to develop standardized metrics indicative of Th2-associated inflammation. Th2-high and Th2-low subgroups were consequently identified and validated against factors associated with disease severity and clinical outcomes.

RESULTS

Mucus levels of IL-5 and IL-13 were elevated in CRS subjects compared to controls, while no significant difference was noted for IL-4. IL-5 and IL-13 high CRS were associated with worse objective measures of disease severity and greater rates of revision surgery. Similar relationships were noted for both cytokines when CRS with nasal polyps (CRSwNP) patients were analyzed separately. Th2-high CRS and Th2-low CRS were then categorized using a scaled IL-5/IL-13 metric. Th2-high CRS was characterized by an increased number of subjects with nasal polyps and comorbid asthma, and worse symptom and computed tomography (CT) scores.

CONCLUSION

The Th2-associated cytokines, IL-5 and IL-13, are detectable in sinonasal mucus and their levels can be used to define Th2-high and Th2-low CRS. Identification of Th2-high and Th2-low endotypes using mucus-based biomarkers could facilitate stratification of CRS subgroups and guide personalized therapies.