Predictive significance of the blood eosinophilia for chronic sinusitis with nasal polyp recurrence: A systematic review and meta-analysis.

Chronic sinusitis with nasal polyps (CRSwNP) is a complex inflammatory condition characterized by recurring nasal polyps, often necessitating repeated interventions. Blood eosinophilia has emerged as a potential biomarker for predicting disease recurrence. The present study aims to assess the predictive significance of blood eosinophilia for the recurrence of nasal polyps. To accomplish this objective, we employed the appropriate search keywords to explore international databases such as Web of Science, PubMed, Embase, and Scopus. Through this process, we extracted scholarly articles that assessed the prognostic value of blood eosinophilia in the recurrence of nasal polyps. The statistical software STATA (version 15) was employed, along with random and fixed-effects models, to appraise the compiled data. Nine articles met inclusion criteria, with a total sample size of 1279 individuals (569 recurrent polyp individuals and 710 non-recurrent polyp individuals). Cumulative Odds ratio analysis revealed that CRSwNP is associated with high blood eosinophile percentage compared to the non-CRSwNP group (p=0.01, OR=1.26, 95%Cl (1.15,1.36). The cut-off value of blood eosinophil percentage (>0.78) had relatively good, and statistically significant predictive potential. No significant publication bias was observed for the included studies. Our findings indicate that the utilization of blood eosinophils holds significant predictive value and can serve as a valuable tool for detecting recurrence in patients with CRSwNP. Based on the outcomes of our comprehensive analysis, we propose a threshold of >0.78 as a reliable indicator for assessing the probability of recurrence in CRSwNP patients.

[Identification of oxidative stress-related biomarkers in chronic rhinosinusitis with nasal polyps using WGCNA combined with machine learning algorithms].

Objective: To identify diagnostic markers related to oxidative stress in chronic rhinosinusitis with nasal polyps (CRSwNP) by analyzing transcriptome sequencing data, and to investigate their roles in CRSwNP. Methods: Utilizing four CRSwNP sequencing datasets, differentially expressed genes (DEGs) analysis, weighted gene co-expression network analysis (WGCNA), and three machine learning methods for Hub gene selection were performed in this study. Subsequent validation was carried out using external datasets, as well as real-time quantitative polymerase chain reaction (Real-time qPCR), and immunofluorescence staining of clinical samples. Moreover, the diagnostic efficacy of the genes was assessed by receiver operating characteristic (ROC) curve, followed by functional and pathway enrichment analysis, immune-related analysis, and cell population localization. Additionally, a competing endogenous RNA (CeRNA) network was constructed to predict potential drug targets. Statistical analysis and plotting were conducted using SPSS 26.0 and Graphpad Prism9 software. Results: Through data analysis and clinical validation, CP, SERPINF1 and GSTO2 were identified among 4 138 DEGs as oxidative stress markers related to CRSwNP. Specifically, the expression of CP and SERPINF1 increased in CRSwNP, whereas that of GSTO2 decreased, with statistically significant differences (P<0.05). Additionally, an area under the curve (AUC)>0.7 indicated their effectiveness as diagnostic indicators. Importantly, functional analysis indicated that these genes were mainly related to lipid metabolism, cell adhesion migration, and immunity. Single-cell data analysis revealed that SERPINF1 was mainly distributed in epithelial cells, stromal cells, and fibroblasts, while CP was primarily located in epithelial cells, and GSTO2 was minimally present in the epithelial cells and fibroblasts of nasal polyps. Consequently, a CeRNA regulatory network was constructed for the genes CP and GSTO2. This construction allowed for the prediction of potential drugs that could target CP. Conclusion: This study successfully identifies CP, SERPINF1 and GSTO2 as diagnostic and therapeutic markers related to oxidative stress in CRSwNP.

Outcome measures for chronic rhinosinusitis with nasal polyps.

BACKGROUND: With the recent proliferation of novel therapeutics for chronic rhinosinusitis with nasal polyps (CRSwNP), there is an immediate need for comprehensive means to assess CRSwNP disease status as well as to determine treatment efficacy. Outcome measures exist in different forms. Patient-reported outcome measures (PROMs) allow patients to provide direct input about their condition that is not possible to obtain in any other way. Common constructs that are measured using PROMs include quality of life or the burden of disease manifestations (e.g., symptom severity). Outcomes may also include the results of objective diagnostic testing/measurement of clinical signs or measured using psychophysical tests. Biomarkers represent an emerging class of outcome measures for CRSwNP and are chosen to directly reflect the active pathophysiologic processes of CRSwNP in the peripheral blood, sinus/polyp tissues, and sinonasal mucus. METHODS: Narrative review of the literature, identifying and describing outcome measures that may be used in the evaluation of CRSwNP and for assessment of treatment responses. RESULTS: In this review, we identify many different outcome measures for CRSwNP that fall under the categories of PROM, objective test, psychophysical test or biomarker. We describe the history of each - including seminal studies - and demonstrate the formal validation, psychometric performance, and limitations of each. CONCLUSIONS: PROMs, objective tests, psychophysical tests and biomarkers represent different classes of outcome measures that are complementary means of assessing CRSwNP disease status and treatment efficacy. The choice or interpretation of a CRSwNP outcome measure should be undertaken with full knowledge of its formal validation, psychometric performance, and limitations.

[Chronic rhinosinusitis with nasal polyposis : A retrospective analysis of therapeutic approaches in 463 patients]. / Chronische Rhinosinusitis mit Polyposis nasi : Retrospektive Analyse des therapeutischen Vorgehens bei 463 Patienten.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease, the treatment of which has undergone significant changes in recent years. In addition to surgical approaches, topical and systemic steroids, and adaptive acetylsalicylic acid (ASA) desensitization, three specific antibodies have complemented the therapeutic portfolio since 2019. METHODS: A retrospective evaluation of all patients who presented as outpatients for the first time due to CRSwNP in 2007 and 2008 (collective A) and 2017 and 2018 (collective B) was performed, up to and including June 2023. RESULTS: The clinical courses of 463 patients (mean age 49.1 years, range 5-82 years; 65.9% male) were included in the analysis. Conservative treatment with nasal corticosteroids started before initial presentation was more frequent in collective B (collective A 43.9% vs. collective B 72.2%). In 278 of the 463 patients (60%; A: 62%, B: 58%), at least one operation on the nasal sinuses had been performed after initial presentation; in 101 of these patients (36.3%) recurrent polyposis (within mean follow-up of 2.4 years) required further treatment. The indication for ASA provocation/desensitization was applied less frequently in collective B, also due to a high discontinuation rate (at least 38%) of the maintenance therapy. Of the total cohort, 16 patients (3.5%; A: n = 8, B: n = 8) were meanwhile switched to antibody therapy at recurrence. CONCLUSION: A step-by-step guideline-orientated approach is recommended in the treatment of CRSwNP. Systemic antibodies as an add-on to nasal corticosteroids are a relatively new therapeutic option for treatment-refractory CRSwNP, which reduces the indication for ASA desensitization, which is associated with a relatively high incidence of side effects and poor compliance.

Sinonasal seromucinous hamartoma: a single institution case series combined with a narrative review of the literature.

PURPOSE: This study aimed to investigate the clinical and histopathological characteristics of sinonasal seromucinous hamartomas (SHs). METHODS: Eight patients with sinonasal SH and treated at a tertiary hospital between November 2005 and September 2023 were included. Additionally, a systematic review of published articles was conducted, analyzing 48 cases of SH described in the literature. RESULTS: Among the eight patients treated at our institution, tumors originated from the posterior nasal cavity in four patients and middle turbinate and middle meatus were the primary origin in two patients each. Coexistence of inflammatory nasal polyps (NPs) was observed in four cases. Histopathologically, four patients exhibited focal respiratory epithelial adenomatoid hamartoma (REAH) features, and low-grade dysplasia was found in one patient. A combined analysis with previous literature revealed that 46.3% of all cases originated in the anterior nasal cavity. The proportions of cases accompanied by NPs and those with focal REAH features were 20.5% and 39.1%, respectively. Additionally, the frequencies of cases exhibiting dysplastic features (5.4%) and recurrence (2.1%) were low. Remarkably, tumors originating from the anterior region tended to have a higher frequency of dysplasia than those originating from the posterior region, although this difference was not statistically significant (p = 0.0996). CONCLUSION: Patients with sinonasal SH showed favorable treatment outcomes following surgical resection. Focal REAH features and accompanying NPs were frequently observed. A substantial proportion of cases originate in the anterior nasal cavity, and these tumors may exhibit a high tendency for dysplasia.

Common Characteristics of Sinonasal Inflammation Associated with IgG4-Related Disease and Other Chronic Inflammatory Diseases: A Retrospective Observational Study.

INTRODUCTION: Immunoglobulin G4-related disease (IgG4-RD) is a systemic inflammatory disease characterized by elevated serum IgG4, tissue infiltration of IgG4-positive cells, and fibrosis. Although a number of IgG4-RD patients show sinonasal involvement, there is little known about sinonasal inflammation associated with IgG4-RD. This study aimed to describe the clinicopathological features of sinonasal inflammation associated with IgG4-RD and to compare with other inflammatory diseases, such as eosinophilic chronic rhinosinusitis (ECRS) and granulomatosis with polyangiitis (GPA). METHODS: A retrospective analysis of clinicopathological features of patients with sinonasal lesions and high serum IgG4 was performed. Patient data were reviewed to determine whether they fulfilled the diagnostic criteria for other inflammatory diseases. RESULTS: Six of 7 patients were diagnosed with IgG4-RD, while 1 patient was diagnosed with GPA. In the 6 patients with IgG4-RD, intranasal findings showed nasal polyps in 3 patients (50%) and nasal crusting in the 3 patients (50%). Computed tomography showed ethmoid sinus involvement in 5 patients (83%). Five of the 6 patients (83%) were diagnosed with IgG4-RD based on nasal biopsy, whereas 1 patient (17%) was diagnosed based on lacrimal gland biopsy. Four patients fulfilled the Japanese epidemiological survey of refractory ECRS (JESREC) criteria. However, none of the patients showed eosinophil infiltration. Although the patient with GPA showed high levels of serum IgG4 and tissue infiltration of IgG4-positive cells in the nasal biopsy, the patient showed common clinical features of GPA. CONCLUSION: Patients with sinonasal inflammation associated with IgG4-RD had similar clinical characteristics with ECRS and GPA. Histopathological findings of the nasal biopsy from clinically diagnosed GPA was consistent with that of IgG4-RD. Sinonasal inflammation associated with IgG4-RD should be diagnosed based not only on tissue infiltration of IgG4-positive cells but in conjunction with clinical findings such as local nasal characteristics, involvement of other organs, and serum antineutrophil cytoplasmic antibody levels. IgG4-RD should be ruled out in patients with eosinophilia without histopathological eosinophil infiltration.

Diagnostic accuracy of clinical visual assessment using endoscopic images for nasal cavity mass lesions.

Objectives: Discrimination of nasal cavity lesions using nasal endoscopy is challenging because of the differences in clinical manifestations and treatment strategies. We aimed to investigate the diagnostic accuracy of clinical visual assessment (CVA) of nasal cavity masses using endoscopic images and determine whether there is a difference according to pathologic class and the examiners' experience. Methods: We collected pathologically confirmed endoscopic images of normal findings, nasal polyp (NP), benign tumor, and malignant tumor (each class contained 100 images) randomly selected. Eighteen otolaryngologists, including six junior residents, six senior residents, and six board-certified rhinologists classified the test set images into four classes of lesions by CVA. Diagnostic performance according to the pathologic class and the examiner's experience level was evaluated based on overall accuracy, F1-score, confusion matrix, and area under the receiver operating characteristic curve (AUC). Results: Diagnostic performance was significantly different according to the pathological class of nasal cavity mass lesions with the overall accuracy reported high in the order of normal, NP, benign tumor, and malignant tumor (0.926 ± 0.100; 0.819 ± 0.135; 0.580 ± 0.112; 0.478 ± 0.187, respectively), F1 score (0.937 ± 0.076; 0.730 ± 0.093; 0.549 ± 0.080; 0.554 ± 0.146, respectively) and AUC value (0.96 ± 0.06; 0.84 ± 0.07; 0.70 ± 0.05; 0.71 ± 0.08, respectively). The expert rhinologist group achieved higher overall accuracy than the resident group (0.756 ± 0.157 vs. 0.680 ± 0.239, p < .05). Conclusion: CVA for nasal cavity mass was highly dependent on the pathologic class and examiner's experience. The overall accuracy was reliably high for normal findings, but low in classifying benign and malignant tumors. Differential diagnosis of lesions solely based on nasal endoscopic evaluation is challenging. Therefore, clinicians should consider further clinical evaluation for suspicious cases.

[Difficult-to-treat chronic rhinosinusitis-when the standard treatment is not effective and biologics are not available]. / Schwierig zu behandelnde chronische Rhinosinusitis ­ wenn die Standardtherapie nicht wirkt und Biologika nicht zur Verfügung stehen.

BACKGROUND: In recent years, significant improvements have been made in the treatment options for uncontrolled chronic rhinosinusitis (CRS) refractory to standard medical and surgical therapy. This is the result of a better understanding of the pathophysiology and the resulting development of biologicals for CRS with nasal polyps (CRSwNP). However, biologics are not (yet) available for all patients in Europe. OBJECTIVE: Based on the session "Difficult-to-treat CRS, when biologics are not available" at the 29th Congress of the European Rhinologic Society (ERS) 2023 in Sofia, Bulgaria, the treatment options for uncontrolled CRS with the exclusion of biologics will be discussed. MATERIALS AND METHODS: The content of the presentations "Is there a place for antibiotics?" "Indications for revision surgery," "Novel systemic treatment options," "Novel local treatment options," and "Phototherapy for nasal polyps" are outlined and supported by a review of the literature. RESULTS: Various treatment options are available for managing uncontrolled CRS, even if biologic treatments are unavailable. Treatment options for type­2 (T2) CRS include steroid rinses, repeated short-term oral steroids, steroid-eluting stents, and extended sinus surgery. In the case of nonsteroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (NERD), acetylsalicylic acid (ASA) desensitization can be considered. Non-T2 endotypes or CRS without nasal polyps (CRSsNP) may benefit from several weeks of macrolides and xylitol rinses. CONCLUSION: To accurately assess the efficacy of second-line therapies for treatment of difficult-to-treat CRS within an endotype-specific framework, additional controlled clinical trials are needed that take into account the heterogeneity of CRS endotypes.

Sinonasal Symptom Correlation With the Postoperative Polyp Scale (POPS).

BACKGROUND: Commonly used endoscopic nasal polyp grading scales have been shown to correlate poorly with symptom scores and quality of life metrics. The recently described Postoperative Polyp Scale (POPS) is a grading system that more accurately characterizes polyp recurrence in postoperative sinus cavities by describing incremental recurrence in relation to the surgically opened sinus cavities. OBJECTIVE: The objective of this study was to determine if the POPS correlated with sinonasal symptoms. METHODS: CRSwNP patients were prospectively administered SNOT-22 questionnaires and graded according to the POPS starting at their 1-month postoperative appointments. Total POPS scores (sum of each side) and Max POPS score (larger value of left and right) were correlated with SNOT-22 total scores and subdomains using Kendall correlation testing. RESULTS: A total of 127 patients were enrolled in the study. Both Total POPS or Max POPS were significantly correlated to the SNOT-22 total score (P < .001, P < .001), Rhinologic (P < .001, P < .001), Extra-Nasal Rhinologic (P < .001, P < .001), Ear/Facial (P < .001, P < .001), and Psychologic (P = .028, P = .017) subdomains. Kendall's tau indicated strong correlation (≥0.3) with Rhinologic subdomain, moderate correlation (.21-.29) with Extra-Nasal Rhinologic and Ear/Facial subdomains, and weak correlation (.1-.19) with Psychologic subdomain. CONCLUSION: Previous endoscopic nasal polyp grading scales poorly correlate with symptoms and patient reported outcome measures. The new POPS moderately correlates with the total SNOT-22 score and strongly correlates with the Rhinologic subdomain, indicating that it may have good potential as a tool to evaluate postoperative CRSwNP patients.

Nasal polyp due to Trichoderma harzianum -A case report.

ABSTRACT: We describe here a case of nasal polyp of the left nose due to Trichoderma harzianum , an emerging fungal infection with an often fatal outcome. Culture showed growth of T. harzianum which was identified by cultural characteristics, microscopic morphology, and molecular methods. The patient was initially treated with a combination of surgical removal of the polyp and oral antibiotics. This case points out that careful scrutiny of nasal polyp is required to ensure accurate diagnosis and appropriate management of cases without recurrence.

Imaging of chronic rhinosinusitis with nasal polyps in the era of biological therapies.

PURPOSE OF REVIEW: Chronic rhinosinusitis (CRS) is a chronic inflammatory disorder of the sinonasal cavities classified into two major phenotypes: CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP). The diagnosis of CRS is based on clinical symptoms associated with imaging and/or nasal endoscopy findings of mucosal inflammation. RECENT FINDINGS: Recently, novel biological therapies have emerged as therapeutic options for CRSwNP. Imaging is helpful in deciding whether surgery is likely to be beneficial and in guiding surgery. It can also help demonstrate a clinical response to medical therapy. However, specific guidelines concerning the role of imaging in CRwNP are lacking. SUMMARY: This article provides a comprehensive and critical multidisciplinary review of the role of conventional radiology, computed tomography (CT), and magnetic resonance imaging (MRI) in the diagnosis and characterization of CRSwNP. Since the complete characterization of nasal polyps on CT or MR images is very challenging, we provide a critical review of the best imaging methods and essential reporting elements used to assess nasal polyps.

Management of patients with chronic rhinosinusitis with nasal polyps in Spain: learnings from a nationwide survey of otorhinolaryngologists.

PURPOSE: To describe the self-reported practices on the diagnosis, treatment, and follow-up of patients with chronic rhinosinusitis with nasal polyps (CRSwNP) by ear, nose, and throat (ENT) specialists in Spain to identify potential areas for management optimization. METHODS: A cross-sectional online survey with 16 questions was carried out. Recruitment was performed by emailing registered ENT specialists in the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC). RESULTS: In total, 127 ENT specialists completed the survey. Fifty-one percent of respondents combined clinical criteria and objective evidence of mucosal inflammation to diagnose CRSwNP. Patient interview and, to a lower degree, a visual analogue scale were the most employed diagnostic tools to quantify symptom severity. Less than half (45%) routinely used the 22-item sino-nasal outcomes test (SNOT-22) to assess the impact of CRSwNP disease in quality of life. The use of patient-reported outcomes and other clinical evaluation tools showed a larger uptake among ENT specialists that worked at an ENT department with an available rhinology unit. Almost all the specialists surveyed (95%) recommended biological treatment, particularly in patients with uncontrolled CRSwNP with respiratory comorbidities (76%), as well as in candidates for revision surgery (66%). CONCLUSION: Spanish otorhinolaryngologists showed a trend toward incorporating CRSwNP guideline recommendations in their clinical practice. The observed low uptake of patient-reported outcomes and objective clinical evaluation tools in routine clinical practise have been identified as areas for optimizing the management of patients with CRSwNP.

Breathing pattern disorder in chronic rhinosinusitis with severe asthma: nasal obstruction and polyps do not increase prevalence.

OBJECTIVES: Chronic rhinosinusitis (CRS) with severe asthma are associated with breathing pattern disorder (BPD). Mouth breathing is a sign of breathing pattern disorder, and nose breathing a fundamental part of breathing pattern retraining for BPD. The prevalence of BPD in relation to CRS subtypes and the relationship of nasal obstruction to BPD in CRS and associated severe asthma is unknown. The breathing pattern assessment tool (BPAT) can identify BPD. Our objective was to thus investigate the prevalence of BPD, nasal airflow obstruction and measures of airway disease severity in CRS with (CRSwNP) and without nasal polyps (CRSsNP) in severe asthma. METHODS: We determined whether CRS status, peak nasal inspiratory flow (PNIF) or polyp disease increased BPD prevalence. Demographic factors, measures of airway function and breathlessness in relation to BPD status and CRS subtypes were also evaluated. RESULTS: 130 Patients were evaluated (n = 69 had BPD). The prevalence of BPD in CRS with severe asthma was 53.1%. There was no difference between BPD occurrence between CRSwNP and CRSsNP. The mean polyp grade and PNIF were not statistically different between the BPD and non-BPD group. The presence of nasal polyps did not increase breathlessness. CONCLUSIONS: BPD and CRS are commonly co-associated. CRS status and nasal obstruction per se does not increase BPD prevalence.

Bacteriology of Different Phenotypes of Chronic Rhinosinusitis.

OBJECTIVES: Chronic rhinosinusitis (CRS) reduces the health-related quality of life and subsequently causes a tremendous socio-economic impact. Although many studies have been conducted, few have identified a relationship between bacteriological characteristics and different phenotypes or endotypes. Therefore, this study aimed to elucidate the recent trends in bacterial cultures from different types of CRS in the Asian population. METHODS: This retrospective case-control study recruited patients diagnosed with CRS who underwent functional endoscopic sinus surgery (FESS) at a tertiary hospital in Taiwan. The patients were classified into those with chronic rhinosinusitis with nasal polyps (CRSwNP)/chronic rhinosinusitis without nasal polyps (CRSsNP), eosinophilic chronic rhinosinusitis (eCRS)/non-eosinophilic chronic rhinosinusitis (NECRS), and central compartment atopic disease (CCAD)/lateral-dominant nasal polyp (LDNP) groups. The demographic data and bacteriological characteristics of the groups were analyzed. RESULTS: We included 503 patients, identifying no significant difference between CRSwNP and CRSsNP for several common bacteria in CRS. The number of Staphylococcus epidermidis isolates in culture was significantly higher in the NECRS group (50.46% vs. 32.56%, p = 0.0003) than that in the eCRS group. The number of methicillin-resistant Staphylococcus aureus (MRSA; 8.51% vs. 2.35%, p = 0.0221) positive isolates was significantly higher in the CCAD group than that in the LDNP group. CONCLUSIONS: This was the first study in Asia to analyze the relationship between bacteriological characteristics and CCAD. MRSA is significantly higher in the CCAD group than that in the LDNP group. Recognizing the unique microbiology of CRSwNP, eCRS, and CCAD is crucial when selecting antimicrobial therapy to lessen the socio-economic impact. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:1071-1076, 2024.

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.

Remission in Type 2 Inflammatory Diseases: Current Evidence, Unmet Needs, and Suggestions for Defining Remission in Chronic Rhinosinusitis with Nasal Polyps.

PURPOSE OF REVIEW: The development of biological therapies for type 2 inflammatory diseases raises the possibility of addressing remission in those dis-immune conditions. No consensus exists for a definition of remission in chronic rhinosinusitis with nasal polyps (CRSwNP). This review aims to critically evaluate the published data to provide the basis for defining remission in CRSwNP. RECENT FINDINGS: The published evidence has yet to provide an unequivocal definition on remission in type 2 inflammatory diseases, in part reflecting differences in approaches to diagnosis and follow-up. A multidimensional evaluation is necessary when considering complete remission, including clinical, inflammatory, and histologic criteria, but how to combine or tailor the three perspectives according to disease severity at baseline or timing of assessment of treatment category is yet to reach consensus. We suggest defining remission starting from the approach taken in asthma and eosinophilic esophagitis, that is, including the resolution of symptoms and improvements in objective parameters of disease severity and/or inflammatory activity. Future studies and consensuses should provide validated criteria with cutoffs for the day-to-day definition of remission. The definition of remission in CRSwNP should include the following criteria, to be verified and maintained for a period of ≥ 12 months: absence of symptoms (nasal obstruction, loss of smell, rhinorrhea as the main ones); no impact of symptoms on quality of life; no need of surgery; no chronic or rescue medications (systemic corticosteroids or antibiotics); and recovery of smell function, possibly evaluated by objective test. Assessment of underlying inflammation should also be considered once accurate and feasible biomarkers are available in clinical practice.

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.