Increased B Cell-Activating Factor Expression Is Associated with Postoperative Recurrence of Chronic Rhinosinusitis with Nasal Polyps

Polyps' Extension and Recurrence in Different Endotypes of Chronic Rhinosinusitis: A Series of 449 Consecutive Patients

Different inflammatory endotypes reflect the heterogeneity of chronic rhinosinusitis with nasal polyps' (CRSwNPs) clinical presentation. This retrospective study aimed to analyze the distribution of polyps in nasal cavities and paranasal sinuses to establish a possible association between CRSwNP endotypes, prognosis, and polyps' extension. This study included 449 adult patients who underwent endoscopic sinus surgery for CRSwNPs between 2009 and 2022. Patients were categorized based on the number of paranasal sinuses involved by polyps. Statistical analyses, including Cox regression, were performed to identify associations between demographic, clinical, and histopathological factors and disease recurrence. CRSwNP patients were stratified into four groups based on the extent of polyp involvement. Asthma and acetylsalicylic acid (ASA) sensitivity were associated with more sinuses involved (p-values = 0.0003 and 0.0037, respectively). Blood eosinophil counts increased with the number of sinuses affected (p-value < 0.0001). The distribution of eosinophilic and non-eosinophilic histotypes varied significantly among these groups (p-value < 0.0001). The risk of CRSwNP recurrence was higher in patients with asthma, higher basophil percentages, and eosinophilic histotype (p-value 0.0104, 0.0001, 0.0118, and 0.0104, respectively). This study suggests a positive association between the number of paranasal sinuses involved by polyps and the severity of CRSwNPs, particularly in patients with eosinophilic histotype, asthma, and ASA sensitivity.

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.

Blood Basophils Relevance in Chronic Rhinosinusitis with Aspirin-Exacerbated Respiratory Disease

Aspirin-exacerbated respiratory disease (AERD) is characterized by eosinophilic asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and intolerance to cyclooxygenase-1 inhibitors. Interest is emerging in studying the role of circulating inflammatory cells in CRSwNP pathogenesis and its course, as well as their potential use for a patient-tailored approach. By releasing IL-4, basophils play a crucial role in activating the Th2-mediated response. The main aim of this study was to, first, investigate the level of the pre-operative blood basophils' values, blood basophil/lymphocyte ratio (bBLR) and blood eosinophil-to-basophil ratio (bEBR) as predictors of recurrent polyps after endoscopic sinus surgery (ESS) in AERD patients. The secondary aim was to compare the blood basophil-related variables of the AERD series (study group) with those of a control group of 95 consecutive cases of histologically non-eosinophilic CRSwNP. The AERD group showed a higher recurrence rate than the control group (p < 0.0001). The pre-operative blood basophil count and pre-operative bEBR were higher in AERD patients than in the control group (p = 0.0364 and p = 0.0006, respectively). The results of this study support the hypothesis that polyps removal may contribute to reducing the inflammation and activation of basophils.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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