TIM-4 in macrophages contributes to nasal polyp formation through the TGF-ß1-mediated epithelial to mesenchymal transition in nasal epithelial cells.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is caused by prolonged inflammation of the paranasal sinus mucosa. The epithelial to mesenchymal transition (EMT) is involved in the occurrence and development of CRSwNP. The T-cell immunoglobulin domain and the mucin domain 4 (TIM-4) is closely related to chronic inflammation, but its mechanism in CRSwNP is poorly understood. In our study, we found that TIM-4 was increased in the sinonasal mucosa of CRSwNP patients and, especially, in macrophages. TIM-4 was positively correlated with α-SMA but negatively correlated with E-cadherin in CRS. Moreover, we confirmed that TIM-4 was positively correlated with the clinical parameters of the Lund-Mackay and Lund-Kennedy scores. In the NP mouse model, administration of TIM-4 neutralizing antibody significantly reduced the polypoid lesions and inhibited the EMT process. TIM-4 activation by stimulating with tissue extracts of CRSwNP led to a significant increase of TGF-ß1 expression in macrophages in vitro. Furthermore, coculture of macrophages and human nasal epithelial cells (hNECs) results suggested that the overexpression of TIM-4 in macrophages made a contribution to the EMT process in hNECs. Mechanistically, TIM-4 upregulated TGF-ß1 expression in macrophages via the ROS/p38 MAPK/Egr-1 pathway. In conclusion, TIM-4 contributes to the EMT process and aggravates the development of CRSwNP by facilitating the production of TGF-ß1 in macrophages. Inhibition of TIM-4 expression suppresses nasal polyp formation, which might provide a new therapeutic approach for CRSwNP.

IL-17A-producing sinonasal MAIT cells in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Diverse immune cells contribute to the pathogenesis of chronic rhinosinusitis (CRS), an inflammatory disease of the nasal cavity and paranasal sinuses. However, whether mucosal-associated invariant T (MAIT) cells are present in human sinonasal tissues remains unclear. Furthermore, the characteristics of sinonasal MAIT cells have not been studied in patients with CRS. OBJECTIVE: We investigated the phenotype, function, and clinical implications of MAIT cells in patients with CRS. METHODS: Peripheral blood and sinonasal tissue were obtained from patients with CRS with (CRSwNP) or without nasal polyps (CRSsNP) and healthy controls. MAIT cells were analyzed by flow cytometry. RESULTS: We found that MAIT cells are present in human sinonasal tissues from healthy controls and patients with CRS. The sinonasal MAIT cell population, but not peripheral blood MAIT cells, from patients with CRSsNP, noneosinophilic CRSwNP (NE-NP), or eosinophilic CRSwNP (E-NP) had a significantly higher frequency of activated cells marked by CD38 expression. In functional analysis, the sinonasal MAIT cell population from NE-NP and E-NP had a significantly higher frequency of IL-17A+ cells but lower frequency of IFN-γ+ or TNF+ cells than control sinonasal tissues. Furthermore, CD38 expression and IL-17A production by sinonasal MAIT cells significantly correlated with disease extent evaluated by the Lund-Mackay computed tomography score in patients with E-NP. CONCLUSIONS: Sinonasal MAIT cells exhibit an activated phenotype and produce higher levels of IL-17A in patients with CRSwNP. These alterations are associated with the extent of disease in patients with E-NP.

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

INTRODUCTION: Antimicrobial peptides and proteins (AMPs) constitute the first line of defense against pathogenic microorganisms in the airway. The association between AMPs and chronic rhinosinusitis with nasal polyps (CRSwNP) requires further investigations. This study is aimed at investigating the expression and regulation of major dysregulated AMPs in the nasal mucosa of CRSwNP. METHODS: The expression of AMPs was analyzed in nasal tissue from patients with eosinophilic (E) CRSwNP and nonECRSwNP and healthy subjects using RNA sequencing. The 10 most abundant AMPs expressed differentially in CRSwNP patients were verified by real-time PCR, and of these, the expression and regulation of secretory leukoprotease inhibitor (SLPI) and clusterin (CLU) were investigated further. RESULTS: The 10 most abundant AMPs expressed differentially in CRSwNP compared to healthy control, regardless of subtypes, included BPIFA1, BPIFB1, BPIFB2, CLU, LTF, LYZ, and SLPI, which were downregulated, and S100A8, S100A9, and HIST1H2BC, which were upregulated. ELISA and immunofluorescence confirmed the decreased expression of SLPI and CLU levels in CRSwNP. SLPI is expressed in both nasal epithelial cells and glandular cells, whereas CLU is mainly expressed in glandular cells. AB/PAS staining further demonstrated that both SLPI and CLU were mainly produced by mucous cells in submucosal glands. Furthermore, the numbers of submucosal glands were significantly decreased in nasal polyp tissue of CRSwNP compared to nasal tissue of controls. SLPI was downregulated by TGF-ß1 and IL-4 in cultured nasal tissues in vitro, while CLU expression was inhibited by TGF-ß1. Glucocorticoid treatment for 2 weeks significantly increased the expression of all downregulated AMPs, but not LYZ. Additionally, budesonide significantly increased the expression of SLPI and CLU in cultured nasal tissues. CONCLUSION: The expression of major antimicrobial proteins is significantly decreased in nasal tissue of CRSwNP. The expression of SLPI and CLU is correlated with the numbers of submucosal glands and regulated by inflammatory cytokines and glucocorticoids.

Subjective and Objective Measurements of Sinonasal Manifestations in Patients With Autoimmune Disorders.

OBJECTIVES/HYPOTHESIS: A number of autoimmune disorders (ADs) are associated with a spectrum of sinonasal manifestations comparable to chronic rhinosinusitis (CRS). Our objective was to study the subjective and objective measurements of sinonasal manifestations of ADs. STUDY DESIGN: Retrospective cohort study. METHODS: All patients with ADs referred to our tertiary care rhinology clinic from 2008 to 2019 with sinonasal symptoms were compared to randomly selected cohorts of noneosinophilic CRS without nasal polyps (neCRSsNP) and eosinophilic CRSsNP (eCRSsNP). Demographic data, along with the 22-item Sino-Nasal Outcome Test (SNOT-22), Lund-Kennedy (LK) endoscopy score, Lund-Mackay (LM) computed tomography (CT) score, nasal crusting, and epistaxis were reviewed at presentation. RESULTS: Fifty-three patients with an AD (26 with sarcoidosis, 14 with systemic lupus erythematosus, 10 with granulomatosis with polyangiitis [GPA], and three with pemphigoid vulgaris) were identified, and compared to 75 randomly selected neCRSsNP patients and 75 eCRSsNP patients. Patients with an AD had an average SNOT-22 score of 44.4 (confidence interval [CI]: 34.6-51.2) compared to 25 (CI: 24.4-25.1) and 29.7 (CI: 20.3-29.7) for neCRSsNP and eCRSsNP patients, respectively (P < .0001), and an average LK endoscopy score of 5.3 (CI: 4.3-6.3), compared to 3.4 (P = .005, CI: 2.7-4) in neCRSsNP and 4.4 in eCRSsNP (P = .2, CI: 3.7-5). There was no significant difference in the CT score compared to both groups. Patients with an AD also scored significantly worse on all four SNOT-33 subdomains, nasal obstruction, nasal crusting, and epistaxis. Additionally, patients with GPA had the worst symptomatic and endoscopy scores. CONCLUSIONS: Patients with ADs presenting with sinonasal symptoms have a more severe subjective and objective presentation than patients with CRS without nasal polyps. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:255-259, 2021.

COVID-19 treatments and pathogenesis including anosmia in K18-hACE2 mice.

The ongoing coronavirus disease 2019 (COVID-19) pandemic is associated with substantial morbidity and mortality. Although much has been learned in the first few months of the pandemic, many features of COVID-19 pathogenesis remain to be determined. For example, anosmia is a common presentation, and many patients with anosmia show no or only minor respiratory symptoms1. Studies in animals infected experimentally with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of COVID-19, provide opportunities to study aspects of the disease that are not easily investigated in human patients. Although the severity of COVID-19 ranges from asymptomatic to lethal2, most experimental infections provide insights into mild disease3. Here, using K18-hACE2 transgenic mice that were originally developed for SARS studies4, we show that infection with SARS-CoV-2 causes severe disease in the lung and, in some mice, the brain. Evidence of thrombosis and vasculitis was detected in mice with severe pneumonia. Furthermore, we show that infusion of convalescent plasma from a recovered patient with COVID-19 protected against lethal disease. Mice developed anosmia at early time points after infection. Notably, although pre-treatment with convalescent plasma prevented most signs of clinical disease, it did not prevent anosmia. Thus, K18-hACE2 mice provide a useful model for studying the pathological basis of both mild and lethal COVID-19 and for assessing therapeutic interventions.

The Microbiome and Chronic Rhinosinusitis.

Chronic rhinosinusitis (CRS) is persistent inflammation and/or infection of the nasal cavity and paranasal sinuses. Recent advancements in culture-independent molecular techniques have enhanced understanding of interactions between sinus microbiota and upper airway microenvironment. The dysbiosis hypothesis-alteration of microbiota associated with perturbation of the local ecological landscape-is suggested as a mechanism involved in CRS pathogenesis. This review discusses the complex role of the microbiota in health and in CRS and considerations in sinus microbiome investigation, dysbiosis of sinus microbiota in CRS, microbial interactions in CRS, and development of preclinical models. The authors conclude with future directions for CRS-associated microbiome research.

Immunological Features of Paranasal Sinus Mucosa in Patients with Graves' Orbitopathy.

Background: Previous studies showed that patients with Graves' orbitopathy (GO) had concomitant mucosal abnormality within the paranasal sinuses. It remains unknown whether the immunological reactions in sinus mucosa affect the orbit inflammation in GO. Methods: Patients with GO underwent sinus computed tomography (CT) scans for sinus mucosal disease by two independent reviewers using the Lund-MacKay systems. Ethmoid mucosal samples were collected during orbital decompression surgeries for patients with GO and correction surgeries for patients with old orbital fractures as controls. Histological analysis and immunofluorescence were performed in all sinus mucosa tissues. Flow cytometry analysis was used to examine the immunological features of sinus mucosa in both GO and control groups. Results: Immunohistochemistry showed that the paranasal sinus mucosa of patients with GO grew swelling, with goblet cell and small vessel proliferation, endothelial cell swelling, and inflammatory cell infiltration. The number of T helper (Th)1, Th17, and gamma-delta T cells in nasal sinus mucosa of patients with GO increased significantly compared with those from controls. Further, the proportion of Th1 cells was significantly correlated with clinical activity score. In addition, there was a decreased number of regulatory T cells in patients with GO. The number of Th2 cells showed no significant difference between the two groups. Finally, the proportion of interleukin-22-producing cell subsets in gamma-delta T cells of patients with GO was significantly increased compared with those from controls. Conclusions: Our observations illustrated a potential pathogenic role of mucosal-infiltrating T cells, which may have the possibility to aggravate inflammatory responses in GO.

Diverse phenotypes and endotypes of fungus balls caused by mixed bacterial colonization in chronic rhinosinusitis.

BACKGROUND: The pathogenic roles of fungus and bacteria in chronic rhinosinusitis (CRS) remain unclear. Recently, we described the bacterial ball, which is distinct from the fungus ball, as an unusual phenotype of bacterial infection. In this study, we investigated the clinical, histopathologic, and immunologic characteristics of sinonasal microorganic materials, including fungus ball and bacterial ball. METHODS: In this study, we enrolled 80 CRS patients with sinonasal microorganic materials and 10 control subjects who underwent skull base surgery or endoscopic dacryocystorhinostomy and had no signs or symptoms of nasal inflammation. All specimens were stained with hematoxylin-eosin, Gomori-methenamine-silver, and Gram stain to identify fungal organisms and Gram-positive/negative bacterial colonies. The expression of tumor necrosis factor (TNF)-α; interleukin (IL)-1ß; S100A7; S100A8/A9; and short, palate, lung, and nasal epithelial clone 1 (SPLUNC1) were evaluated by enzyme-linked immunosorbent assay using sinus lavage fluid. RESULTS: We histologically classified sinonasal microorganic materials into the following 4 groups: fungus ball (n = 45); bacterial ball (n = 6); mixed ball (formed by a mixture of fungus and bacteria, n = 27); and double ball (formed by separate fungal and bacterial balls, n = 2). Compared with the fungus ball, the mixed ball was more frequently detected in immunocompromised patients (p < 0.0001). In addition, TNF-α expression was significantly higher in fungus and mixed balls than in control, whereas the mixed ball showed higher expression of IL-1ß compared with the fungus ball. Moreover, the expression of S100A7 and S100A8/A9 protein in the mixed ball was significantly decreased when compared with the fungus ball, whereas there was no significant difference in SPLUNC1 expression between fungus and mixed balls. CONCLUSION: Our findings suggest that fungal and bacterial interactions are diverse in CRS. Specifically, the mixed ball is prevalent in CRS with an immunocompromised state and it may decrease epithelial barrier function.

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.

Impact of Allergic Rhinitis on Nasal Mucociliary Clearance Time in Children.

BACKGROUND: Mucociliary clearance is one of the most important protective functions of the airway. Previous studies, checking the influence of allergic rhinitis (AR) on mucociliary clearance time (MCT), were made on small patient groups and brought contradictive results. OBJECTIVES: The aim of the study is to confirm whether AR in children influences MCT. METHODS: The examined group consisted of 842 AR children. A total of 96 children with no history of allergy rhinitis served as a comparative group. All patients underwent saccharin and skin prick tests and tests for blood eosinophilia, nasal eosinophilia, vitamin D3 serum concentration, total and specific IgE serum concentration. RESULTS: Nasal MCT was significantly longer in AR patients (mean ± SD: 10.5 ± 5.65 min) compared to controls (mean ± SD: 7.25 ± 4.3 min). Percentage of eosinophils in nasal smears in patients was significantly higher compared to controls and a weak, but significant positive correlation was observed between the percentage and MCT (r > 0.10, p < 0.008). Patients with intermittent and persistent moderate/ severe AR had significantly longer MCT and higher eosinophilia in nasal smears compared both to patients with intermittent and persistent mild RA and controls. No correlation was observed between MCT and: participant's age, total serum IgE, vitamin D3 serum concentration, absolute number or percentage of eosinophils in blood, prick test results or duration of illness. CONCLUSIONS: AR affects the mucociliary clearance in children, and its deterioration is related to more severe rhinitis with higher intensity of local nasal inflammation, reflected in nasal smear eosinophilia.

Aspergillus fumigatus induction of IL-33 expression in chronic rhinosinusitis is PAR2-dependent.

OBJECTIVE: In the pathophysiology of chronic rhinosinusitis with nasal polyps (CRSwNP), Aspergillus fumigatus (A. fumigatus) can upregulate IL-33 from human sinonasal epithelial cells (SNECs), which then activates innate lymphoid cells causing release of IL-13, an important driver of allergic inflammation. However, the mechanism by which A. fumigatus mediates the induction of IL-33 expression remains to be elucidated. The objectives of this study were to determine the specific fungal component(s) and the receptor responsible for mediating the A. fumigatus induced increase in IL-33 expression in SNECs from patients with CRSwNP. METHODS: SNECs from CRSwNP patients were cultured and stimulated with various fungal components in the absence or presence of 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride, an irreversible serine protease inhibitor, or GB83, a reversible protease activated receptor 2 (PAR2) inhibitor. IL-33 expression was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR). PAR2 expression was examined in inflamed mucosa from nonatopic control and CRSwNP patients. RESULTS: Elevation of IL-33 expression in primary SNECs was found in response to fungal protease but not fungal cell wall components. PAR2 expression was elevated in inflamed mucosa from CRSwNP patients in comparison to controls. The A. fumigatus fungal protease-mediated elevation in IL-33 expression by human SNECs was serine protease- and PAR2-dependent. CONCLUSION: These data suggest that serine protease activity of A. fumigatus is capable of inducing IL-33 expression in CRSwNP SNECs via PAR2, a potential therapeutic target in the treatment of CRSwNP. LEVEL OF EVIDENCE: NA Laryngoscope, 129:2230-2235, 2019.

Induction of human regulatory innate lymphoid cells from group 2 innate lymphoid cells by retinoic acid.

BACKGROUND: Group 2 innate lymphoid cells (ILC2s) play critical roles in induction and exacerbation of allergic airway inflammation. Thus clarification of the mechanisms that underlie regulation of ILC2 activation has received significant attention. Although innate lymphoid cells are divided into 3 major subsets that mirror helper effector T-cell subsets, counterpart subsets of regulatory T cells have not been well characterized. OBJECTIVE: We sought to determine the factors that induce regulatory innate lymphoid cells (ILCregs). METHODS: IL-10+ ILCregs induced from ILC2s by using retinoic acid (RA) were analyzed with RNA-sequencing and flow cytometry. ILCregs were evaluated in human nasal tissue from healthy subjects and patients with chronic rhinosinusitis with nasal polyps and lung tissue from house dust mite- or saline-treated mice. RESULTS: RA induced IL-10 secretion by human ILC2s but not type 2 cytokines. IL-10+ ILCregs, which were converted from ILC2s by means of RA stimulation, expressed a regulatory T cell-like signature with expression of IL-10, cytotoxic T lymphocyte-associated protein 4, and CD25, with downregulated effector type 2-related markers, such as chemoattractant receptor-homologous molecule on TH2 cells and ST2, and suppressed activation of CD4+ T cells and ILC2s. ILCregs were rarely detected in human nasal tissue from healthy subjects or lung tissue from saline-treated mice, but numbers were increased in nasal tissue from patients with chronic rhinosinusitis with nasal polyps and in lung tissue from house dust mite-treated mice. Enzymes for RA synthesis were upregulated in airway epithelial cells during type 2 inflammation in vivo and by IL-13 in vitro. CONCLUSION: We have identified a unique immune regulatory and anti-inflammatory pathway by which RA converts ILC2s to ILCregs. Interactions between airway epithelial cells and ILC2s play an important roles in the generation of ILCregs.

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.

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-1ß, 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.

Deletion of Nrf2 enhances susceptibility to eosinophilic sinonasal inflammation in a murine model of rhinosinusitis.

BACKGROUND: Oxidative stress exacerbates lower airway diseases including asthma and chronic obstructive pulmonary disease (COPD); however, its role in upper airway (sinonasal) chronic inflammatory disorders is less clear. Nuclear erythroid 2 p45-related factor (Nrf2) is an endogenous mechanism that upon activation invokes an antioxidant response pathway via nuclear translocation and upregulation of cytoprotective genes. We sought to determine whether deletion of Nrf2 enhances susceptibility to allergic sinonasal inflammation in vivo. METHODS: Nrf2-/- mice were subjected to the ovalbumin (Ova)-induced murine model of rhinosinusitis and indices of sinonasal inflammation and epithelial barrier dysfunction were assessed. RESULTS: We show that deletion of Nrf2 results in enhances indices of allergen-induced sinonasal inflammation including aggravated eosinophil accumulation and goblet cell hyperplasia. An exaggerated increase in epithelial derived inflammatory cytokines including interleukin 33 (IL-33) and thymic stromal lymphopoietin (TSLP) was observed in the nasal lavage fluid and sinonasal mucosal tissue of Nrf2-/- mice. Furthermore, Nrf2-/- mice showed heightened Ova-induced barrier dysfunction as measured by serum albumin accumulation in nasal lavage fluid of mice. CONCLUSION: These data show that the endogenous Nrf2 pathway limits Ova-induced sinonasal inflammation, epithelial derived inflammatory cytokine production, and epithelial barrier dysfunction in vivo and identify a potential therapeutic target in the management of allergic sinonasal inflammatory disorders. This is the first study to our knowledge which shows that Nrf2 regulates allergic inflammation in the sinonasal cavity in vivo.

Relative abundance of nasal microbiota in chronic rhinosinusitis by structured histopathology.

BACKGROUND: Chronic rhinosinusitis (CRS) is an inflammatory disease process with several different phenotypes. Recent data has shown that CRS phenotypes maintain distinct nasal microbiota that may predict surgical outcomes. Nasal microbiota and structured histopathologic reporting have the potential to further differentiate subtypes and provide additional insight into the pathophysiology of CRS. METHODS: Sinus swabs collected during functional endoscopic sinus surgery (FESS) were studied by polymerase chain reaction analysis of 16S ribosomal RNA. A structured histopathology report of 13 variables was utilized to analyze sinus tissue removed during FESS. Histopathology variables and relative abundance of nasal microbiota were compared among CRS patients. RESULTS: A total of 51 CRS patients who underwent FESS were included. Relative abundance of the Firmicutes phylum in nasal microbiota of CRS patients was associated with presence of neutrophilic infiltrate (27.47 ± 44.75 vs 9.21 ± 11.84, p < 0.029), presence of mucosal ulceration (47.67 ± 45.52 vs 13.27 ± 26.48, p < 0.041), presence of squamous metaplasia (5562.70 ± 2715.66 vs 3563.73 ± 2580.84, p < 0.035), and absence of Charcot-Leyden crystals (5423.00 ± 3320.57 vs 679.94 ± 1653.66, p < 0.001). Relative abundance of the Bacteroidetes phylum in nasal microbiota of CRS patients was associated with increased severity of inflammatory degree (p < 0.004) and presence of mucosal ulceration (p < 0.004). CONCLUSION: Distinct histopathologic features of CRS are associated with relative abundance of nasal microbiota phyla, specifically Firmicutes and Bacteroidetes. These findings contribute to the growing body of literature on microbiota in sinonasal disease and may have important implications for understanding pathophysiologic mechanisms of CRS subtypes and disease management.

The use of immunohistochemical methods in the study of morphofunctional features of the human paranasal sinuses: literature review.

OBJECTIVE: Introduction:Chronic inflammatory diseases of the mucous membrane of the nose, paranasal sinuses, and pharynx are the most widespread pathology of the upper airways. The thorough study of the features of the organization of local immune protection of the mucous membrane of the paranasal sinuses is crucial for the deep understanding of the causes of the onset and development of this and other pathologies of the paranasal sinuses, the choice of methods of diagnostics and treatment. Consequently, immunohistochemical studies are of great potential and have become preferable for great number of researchers. The aim: The paper was aimed at the analysis of the publications on the use of immunohistochemical methods in the study of the structural and functional features of the paranasal sinuses. PATIENTS AND METHODS: Materials and methods: The bibliosemantic method has been used during the study. Findings of the current research works on the use of immunohistochemical methods in the study of the paranasal sinuses have been analyzed. RESULTS: Review:The findings of the analysis shows that the use of immunohistochemical methods in the otorhinolaryngology is becoming more and more popular in the study of both morphofunctional features of the paranasal sinuses and in various experimental studies. CONCLUSION: Conclusion: The use of immunohistochemical methods in the study of the paranasal sinuses in both clinical otorhinolaryngology and theoretical morphology is relevant to date and is considered reasonable and perspective.

Efficacy of add-on sublingual immunotherapy for adults with asthma: A meta-analysis and systematic review.

BACKGROUND: Sublingual immunotherapy (SLIT) reduces symptom scores and the use of rescue medication in children with allergic asthma, but the effect of SLIT therapy in adult patients has not been reported. OBJECTIVE: To examine the efficacy and adverse effects of SLIT add-on vs conventional medication in adult patients with mild to moderate asthma. METHODS: We systematically searched the MEDLINE, Embase, Cochrane, and Central databases. Eligible studies included adult patients with allergic asthma who received either SLIT or standard care. Standard mean differences were used as measures of efficacy in a random-effects model. RESULTS: Twenty trials that included 2,288 patients in the SLIT add-on group and 1,268 patients in the traditional therapy group were identified as eligible for final analysis. Compared with traditional therapy, SLIT add-on therapy was associated with significant improvements in lower and upper airway scores, a higher forced expiratory volume in 1 second, and maximal expiratory flow at 25% of forced vital capacity, and improved bronchial reactivity. Drug consumptions were significantly decreased as well. Airway inflammatory parameters, such as nasal eosinophil infiltration, were markedly improved. CONCLUSION: The findings of this study suggested that long-term SLIT add-on therapy is a complementary treatment for adults with asthma in addition to conventional medicine. It not only reduces symptom scores but also improves lung function and airway inflammation.

Immunoglobulin G4-related disease of the paranasal sinuses.

Immunoglobulin G4-related disease (IgG4-RD) is becoming increasingly documented. It was first described in relation to autoimmune pancreatitis. Features of the disease include tissue infiltration by IgG4 plasma cells with associated fibrosis and the growth of pseudotumours. A 71-year-old woman presented with increasing right cheek swelling and mild proptosis. Ten years earlier, she had a similar presentation and was diagnosed with an inflammatory pseudotumour. Examination revealed a lesion in the right nasal cavity. CT and MRI confirmed a mass within the right maxillary antrum extending into the nasal cavity. Endoscopic biopsies showed florid plasma cell infiltrate with marked increase in IgG+ plasma cells. Immunostaining expressed IgG4 (70%). She was started on a course of prednisolone and her symptoms resolved. IgG4-RD is becoming an emerging disease entity. Its involvement in the paranasal sinuses can mimic nasal tumours. Major surgical resection should be avoided as patients can often be treated medically.

Focus on the Involvement of the Nose and Paranasal Sinuses in Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss Syndrome): Nasal Cytology Reveals Infiltration of Eosinophils as a Very Common Feature.

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a necrotizing vasculitis that predominantly affects small- to medium-sized vessels. It is characterized by a wide spectrum of extrapulmonary symptoms, including sinonasal and paranasal sinus abnormalities. These are the most common features of this disease, constituting diagnostic criteria for EGPA. However, the actual clinical features, cellular mechanisms and impact on patients' quality of life (QoL) are still a matter of study. METHODS: Thirty-nine EGPA patients underwent multidimensional rhinological evaluations, including rhinofibroscopy, nasal cytology, and QoL questionnaires. This was coupled with respiratory and rheumatological assessments. RESULTS: Twenty-eight patients were diagnosed with chronic rhinosinusitis (CRS). Of these, 18 had nasal polyposis (NP). Chronic rhinitis was diagnosed in 10 patients. Of these, 3 had allergic rhinitis (AR) and seven had non-AR (NAR). Overall, only 1 patient (2.6%) was normal. Nasal cytology showed that hypereosinophilia was present in 17/28 patients with CRS, 4/7 patients with NAR and all patients with AR. SNOT-22 and SF-36 showed a severe impact of nasal symptoms on QoL. No differences in asthma control or rheumatological patterns for EGPA were observed among patients with or without NP. CONCLUSIONS: Even when the rheumatological assessment scored EGPA "under control" according to the Birmingham Vasculitis Activity Score and Vasculitis Damage Index, sinonasal diseases and related nasal inflammatory processes were not controlled. Therefore, there is a need for clinical monitoring and targeted treatment to control the inflammatory processes and improve the QoL of EGPA patients.