Evidence of microbiota dysbiosis in chronic rhinosinusitis

Cystic fibrosis pathogens persist in the upper respiratory tract following initiation of elexacaftor/tezacaftor/ivacaftor therapy

Elexacaftor/tezacaftor/ivacaftor (ETI) therapy has revolutionized the treatment of cystic fibrosis (CF) for most affected individuals but the effects of treatment on sinus microbiota are still unknown. Changes to the airway microbiota in CF are associated with disease state and alterations to the bacterial community after ETI initiation may require changes to clinical management regimens. We collected sinus swab samples from the middle meatus in an observational study of 38 adults with CF and chronic rhinosinusitis (CRS) from 2017 to 2021 and captured the initiation of ETI therapy. We performed 16S and custom amplicon sequencing to characterize the sinus microbiota pre- and post-ETI. Real-time quantitative PCR (RT-qPCR) was performed to estimate total bacterial abundance. Sinus samples from people with CF (pwCF) clustered into three community types, dependent on the dominant bacterial organism: a Pseudomonas-dominant, Staphylococcus-dominant, and mixed dominance cluster. Shannon's diversity index was low and not significantly altered post-ETI. Total bacterial load was not significantly lowered post-ETI. Pseudomonas spp. abundance was significantly reduced post-ETI, but eradication was not observed. Staphylococcus spp. became the dominant organism in most individuals post-ETI and we showed the presence of methicillin-resistant Staphylococcus aureus (MRSA) in the sinus both pre- and post-ETI. We also demonstrated that the sinus microbiome is predictive of the presence of Pseudomonas spp., Staphylococcus spp., and Serratia spp. in the sputum. Pseudomonas spp. and Staphylococcus spp., including MRSA, persist in the sinuses of pwCF after ETI therapy, indicating that these pathogens will continue to be important in CF airway disease management in the era of highly effective modulator therapies (HEMT).IMPORTANCEHighly effective modulator therapies (HEMT), such as elexacaftor/tezacaftor/ivacaftor (ETI), for cystic fibrosis (CF) have revolutionized patient care and quality of life for most affected individuals. The effects of these therapies on the microbiota of the airways are still unclear, though work has already been published on changes to microbiota in the sputum. Our study presents evidence for reduced relative abundance of Pseudomonas spp. in the sinuses following ETI therapy. We also show that Staphylococcus spp. becomes the dominant organism in the sinus communities of most individuals in this cohort after ETI therapy. We identified methicillin-resistant Staphylococcus aureus (MRSA) in the sinus microbiota both pre- and post-therapy. These findings demonstrate that pathogen monitoring and treatment will remain a vital part of airway disease management for people with cystic fibrosis (pwCF) in the era of HEMT.

Characterising the allergic fungal rhinosinusitis microenvironment using full-length 16S rRNA gene amplicon sequencing and fungal ITS sequencing

INTRODUCTION

Allergic fungal rhinosinusitis (AFRS) is a severe phenotype of chronic rhinosinusitis with nasal polyposis (CRSwNP), characterised by localised and exaggerated type 2 inflammation. While fungal antigenic stimulation of unregulated Th2-mediated inflammation is the core pathophysiological mechanism, the direct and synergistic role of bacteria in disease modification is a pervasive hypothesis. We set out to define the microenvironment of AFRS to elucidate virulent organisms that may be implicated in the pathophysiology of AFRS.

METHODOLOGY

We undertook a cross-sectional study of AFRS patients and non-fungal CRSwNP patients. Demographics, disease severity, culture and microbiome sequences were analysed. Multimodality microbiome sequencing included short-read next-generation sequencing (NGS) on the Illumina Miseq (16S rRNA and ITS) and full-length 16S rRNA sequencing on the Oxford Nanopore Technologies GridION (ONT).

RESULTS

Thirty-two AFRS and 29 non-fungal CRSwNP patients (NF) were included in this study. Staphylococcus aureus was the dominant organism cultured and sequenced in both AFRS and NF groups (AFRS 27.54%; NF 18.04%; p = .07). Streptococcus pneumoniae (AFRS 12.31%; NF 0.98%; p = .03) and Haemophilus influenzae (AFRS 15.03%; NF 0.24%; p = .005) were significantly more abundant in AFRS. Bacterial diversity (Shannon's index) was considerably lower in AFRS relative to NF (AFRS 0.6; NF 1.0, p = .008). Aspergillus was the most cultured fungus in AFRS (10/32, 31.3%). The AFRS sequenced mycobiome was predominantly represented by Malassezia (43.6%), Curvularia (18.5%) and Aspergillus (16.8%), while the NF mycobiome was nearly exclusively Malassezia (84.2%) with an absence of Aspergillus or dematiaceous fungi.

CONCLUSION

A low diversity, dysbiotic microenvironment dominated by Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae characterised the bacterial microbiome of AFRS, with a mycobiome abundant in Malassezia, Aspergillus and Curvularia. While Staphylococcus aureus has been previously implicated in AFRS through enterotoxin superantigen potential, Streptococcus pneumoniae and Haemophilus influenzae are novel findings that may represent alternate cross-kingdom pathophysiological mechanisms.

Prevalence of the Cefazolin Inoculum Effect (CzIE) in Nasal Colonizing Methicillin-Susceptible Staphylococcus aureus in Patients from Intensive Care Units in Colombia and Use of a Modified Rapid Nitrocefin Test for Detection

The cefazolin inoculum effect (CzIE) has been associated with poor clinical outcomes in patients with MSSA infections. We aimed to investigate the point prevalence of the CzIE among nasal colonizing MSSA isolates from ICU patients in a multicenter study in Colombia (2019-2023). Patients underwent nasal swabs to assess for S. aureus colonization on admission to the ICU and some individuals had follow-up swabs. We performed cefazolin MIC by broth-microdilution using standard and high-inoculum and developed a modified nitrocefin-based rapid test to detect the CzIE. Whole genome sequencing was carried out to characterize BlaZ types and allotypes, phylogenomics and Agr-typing. All swabs were subjected to 16S-rRNA metabarcoding sequencing to evaluate microbiome characteristics associated with the CzIE. A total of 352 patients were included; 46/352 (13%) patients were colonized with S. aureus; 22% (10/46) and 78% (36/46) with MRSA and MSSA, respectively. Among 36 patients that contributed with 43 MSSA colonizing isolates, 21/36 (58%) had MSSA exhibiting the CzIE. BlaZ type A and BlaZ-2 were the predominant type and allotype in 56% and 52%, respectively. MSSA belonging to CC30 were highly associated with the CzIE and SNP analyses supported transmission of MSSA exhibiting the CzIE among some patients of the same unit. The modified nitrocefin rapid test had 100%, 94.4% and 97.7% sensitivity, specificity and accuracy, respectively. We found a high prevalence point prevalence of the CzIE in MSSA colonizing the nares of critically-ill patients in Colombia. A modified rapid test was highly accurate in detecting the CzIE in this patient population.

Effects of Nasal Solution Incorporating Resveratrol and Carboxymethyl-Β-Glucan in Preschool Non-Atopic Children with Wheezing

Upper respiratory tract infections (URTI) account for more than 80% of wheezing episodes in children with a high incidence of hospitalization in preschool age. Most children with symptoms of wheezing during an URTI are usually non-atopic. As the majority of wheezing episodes resulting from URTI are attributed to viral triggers, several studies have suggested the potential anti-inflammatory and antiviral properties of resveratrol. This study aims to identify the effect of resveratrol for pediatric non-atopic patients with recurrent wheezing triggered by URTIs. We conducted a prospective single-blind study to assess the effectiveness of a short course of nasal solutions incorporating resveratrol and carboxymethyl-β-glucan, administered for 7 days at the onset of URTIs, compared to standard nasal lavage with 0.9% saline solution. A total of 19 patients entered the active group, 20 patients were assigned to the placebo group. The comparison of overall wheezing days (p < 0.001), mean wheezing days per month (p < 0.01), and wheezing episodes per patient (p < 0.001) in the two groups showed a significant reduction in the group receiving resveratrol compared with the placebo group, with less hospital access (p < 0.001) and oral corticosteroid administration (p < 0.01). Our findings seem to suggest that, in non-atopic children with recurrent wheezing secondary to URTIs, nasal resveratrol could be effective to prevent or reduce the occurrence of wheezing, when started from the onset of upper airway symptoms.

S. aureus biofilm properties correlate with immune B cell subset frequencies and severity of chronic rhinosinusitis

Staphylococcus aureus mucosal biofilms are associated with recalcitrant chronic rhinosinusitis (CRS). However, S. aureus colonisation of sinus mucosa is frequent in the absence of mucosal inflammation. This questions the relevance of S. aureus biofilms in CRS etiopathogenesis. This study aimed to investigate whether strain-level variation in in vitro-grown S. aureus biofilm properties relates to CRS disease severity, in vitro toxicity, and immune B cell responses in sinonasal tissue from CRS patients and non-CRS controls. S. aureus clinical isolates, tissue samples, and matched clinical datasets were collected from CRS patients with nasal polyps (CRSwNP), CRS without nasal polyps (CRSsNP), and controls. B cell responses in tissue samples were characterised by FACS. S. aureus biofilms were established in vitro, followed by measuring their properties of metabolic activity, biomass, colony-forming units, and exoprotein production. S. aureus virulence was evaluated using whole-genome sequencing, mass spectrometry and application of S. aureus biofilm exoproteins to air-liquid interface cultures of primary human nasal epithelial cells (HNEC-ALI). In vitro S. aureus biofilm properties were correlated with increased CRS severity scores, infiltration of antibody-secreting cells and loss of regulatory B cells in tissue samples. Biofilm exoproteins from S. aureus with high biofilm metabolic activity had enriched virulence genes and proteins, and negatively affected the barrier function of HNEC-ALI cultures. These findings support the notion of strain-level variation in S. aureus biofilms to be critical in the pathophysiology of CRS.

Bacterial and fungal communities in chronic rhinosinusitis with nasal polyps

OBJECTIVE

Multiple inflammatory mechanisms dynamically interact in the development of chronic rhinosinusitis with nasal polyps (CRSwNP). Disruption of the relationship between host and environmental factors on the mucosal surface leads to the development of inflammation. Microorganisms constitute the most important part of environmental factors.

METHODS

28 volunteers (18 CRSwNP patients and 10 healthy individuals) were included in the study. Eight patients were recurrent nasal polyposis cases, and the remaining were primary cases. Swab samples were taken from the middle meatus under endoscopic examination from all participants. After DNA extraction, a library was created with the Swift Amplicon 16S + ITS kit and sequenced with Illumina Miseq. Sequence analysis was performed using QIIME, UNITE v8.2 database for ITS and Silva v138 for 16S rRNA.

RESULTS

The predominant bacteria in all groups were Firmicutes, Proteobacteria, Actinobacteria as phyla and Staphylococcus, Corynebacterium, Sphingomonas as genera. Comparison of bacterial communities of CRSwNP patients and control group highlighted Corynebacterium, as the differentiating taxa for control group and Streptococcus, Moraxella, Rothia, Micrococcus, Gemella, and Prevotella for CRSwNP patients. The predominant fungal genus in all groups was Malassezia. Staphylococcus; showed a statistically significant negative correlation with Dolosigranulum. Corynebacterium had a positive correlation with Anaerococcus, and a negative correlation with Neisseria, Prevotella, Fusobacterium and Peptostreptococcus.

CONCLUSION

Nasal microbiome of CRSwNP patients shows greater inter-individual variation than the control group. Corynebacterium is less abundant in patients with CRSwNP compared to the control group. Malassezia is the predominant fungus in the nasal cavity and paranasal sinuses and correlates positively with the abundance of Corynebacterium.

Elexacaftor-tezacaftor-ivacaftor decreases pseudomonas abundance in the sinonasal microbiome in cystic fibrosis

BACKGROUND

Chronic rhinosinusitis (CRS) is common in individuals with cystic fibrosis (CF) and is marked by chronic inflammation and episodes of infection that negatively impact quality of life. Several studies have shown that elexacaftor-tezacaftor-ivacaftor (ETI) improves symptoms and examination findings in CF-CRS. The current study determines the effect of ETI on the sinonasal microbiota in CF.

METHODS

Sinonasal samples were collected under endoscopic visualization before and after starting ETI. Samples were subjected to 16S amplicon sequencing and sequences were processed with the QIIME2 pipeline with subsequent analysis using the vegan R-package.

RESULTS

Twenty-nine individual baseline samples and 23 sample pairs pre-/post-ETI were available. At baseline, the cohort had samples dominated by Staphylococcus, and alpha diversity was lower than that of a published reference set of individuals without sinonasal disease. Individuals with prior sinus surgery had lower alpha diversity as measured by Shannon Index, Observed Richness, and Faith's phylogenetic diversity Index. Beta diversity differed between individuals with and without allergic rhinitis, with higher Staphylococcus abundance in those with allergic rhinitis. No change in alpha or beta diversity was seen after a median of 9 months on ETI. With ETI, the Pseudomonas genus and the genus containing Burkholderia decreased in samples containing these taxa at baseline. Pseudomonas abundance decreased with treatment as measured by qPCR. Core sinonasal microbiome members Staphylococcus, Corynebacterium, and Streptococcus were unchanged, while Moraxella increased with ETI.

CONCLUSIONS

Treatment with ETI leads to a reduction in Pseudomonas abundance within the sinonasal microbiome of individuals with Pseudomonas at baseline.

Fungal and Bacterial Microbiome in Sinus Mucosa of Patients with and without Chronic Rhinosinusitis

OBJECTIVES

Dysbiosis of the sinonasal microbiome has been implicated in the pathogenesis of chronic rhinosinusitis (CRS). However, the mycobiome remains largely understudied, and microbial alterations associated with specific CRS subtypes have yet to be delineated. The objective of this study is to investigate the fungal and bacterial microbiome of sinus mucosa in CRS patients with and without nasal polyposis (CRSwNP and CRSsNP) versus healthy controls.

METHODS

Sinus mucosa was obtained from 92 patients (31 CRSsNP, 31 CRSwNP, and 30 controls) undergoing endoscopic sinus/skull base surgery. Data regarding demographics, Lund-MacKay scores, and histopathology were collected. Fungal and bacterial microbiome analysis was performed utilizing internal transcribed spacer amplicon and 16S rRNA sequencing.

RESULTS

Beta diversity of the sinonasal mycobiome differed significantly between CRS and controls (p = 0.001) and between CRSwNP and controls (p = 0.049), but not between CRSwNP and CRSsNP (p = 0.32) nor between CRSsNP and controls (p = 0.06). With respect to the bacterial microbiome, significantly lower alpha diversity was observed between CRS and controls (p < 0.001), CRSwNP versus controls (p < 0.001), and CRSsNP versus controls (p < 0.001). Beta diversity was also significantly different at the genus level between CRSwNP and CRSsNP (p = 0.019), CRSwNP and controls (p = 0.002)), and CRSsNP and controls (p < 0.001). However, alpha and beta diversity did not differ significantly between CRS patients with/without eosinophils or correlate with Lund-MacKay scores.

CONCLUSIONS

Differences in mycobiota diversity in CRS patients in comparison with controls suggest that alterations in the mycobiome may contribute to disease pathogenesis. Our findings also confirmed that diminished diversity among bacterial communities is associated with CRS and that significant differences are present in microbial composition between CRSwNP and CRSsNP.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:1054-1062, 2024.

Remodeling of Paranasal Sinuses Mucosa Functions in Response to Biofilm-Induced Inflammation

Rhinosinusitis (RS) is an acute (ARS) or chronic (CRS) inflammatory disease of the nasal and paranasal sinus mucosa. CRS is a heterogeneous condition characterized by distinct inflammatory patterns (endotypes) and phenotypes associated with the presence (CRSwNP) or absence (CRSsNP) of nasal polyps. Mucosal barrier and mucociliary clearance dysfunction, inflammatory cell infiltration, mucus hypersecretion, and tissue remodeling are the hallmarks of CRS. However, the underlying factors, their priority, and the mechanisms of inflammatory responses remain unclear. Several hypotheses have been proposed that link CRS etiology and pathogenesis with host (eg, "immune barrier") and exogenous factors (eg, bacterial/fungal pathogens, dysbiotic microbiota/biofilms, or staphylococcal superantigens). The abnormal interplay between these factors is likely central to the pathophysiology of CRS by triggering compensatory immune responses. Here, we discuss the role of the sinonasal microbiota in CRS and its biofilms in the context of mucosal zinc (Zn) deficiency, serving as a possible unifying link between five host and "bacterial" hypotheses of CRS that lead to sinus mucosa remodeling. To date, no clear correlation between sinonasal microbiota and CRS has been established. However, the predominance of Corynebacteria and Staphylococci and their interspecies relationships likely play a vital role in the formation of the CRS-associated microbiota. Zn-mediated "nutritional immunity", exerted via calprotectin, alongside the dysregulation of Zn-dependent cellular processes, could be a crucial microbiota-shaping factor in CRS. Similar to cystic fibrosis (CF), the role of SPLUNC1-mediated regulation of mucus volume and pH in CRS has been considered. We complement the biofilms' "mechanistic" and "mucin" hypotheses behind CRS pathogenesis with the "structural" one - associated with bacterial "corncob" structures. Finally, microbiota restoration approaches for CRS prevention and treatment are reviewed, including pre- and probiotics, as well as Nasal Microbiota Transplantation (NMT).

Host-microbe interactions in chronic rhinosinusitis biofilms and models for investigation

Chronic rhinosinusitis (CRS) is a debilitating condition characterized by long-lasting inflammation of the paranasal sinuses. It affects a significant portion of the population, causing a considerable burden on individuals and healthcare systems. The pathogenesis of CRS is multifactorial, with bacterial infections playing a crucial role in CRS development and persistence. In recent years, the presence of biofilms has emerged as a key contributor to the chronicity of sinusitis, further complicating treatment and exacerbating symptoms. This review aims to explore the role of biofilms in CRS, focusing on the involvement of the bacterial species Staphylococcus aureus and Pseudomonas aeruginosa, their interactions in chronic infections, and model systems for studying biofilms in CRS. These species serve as an example of how microbial interplay can influence disease progression and exemplify the need for continued investigation and innovation in CRS research.

The Effect of Corticosteroids on Sinus Microbiota in Chronic Rhinosinusitis Patients with Nasal Polyposis

BACKGROUND

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is a multifactorial disease with no known single cause, but it is thought that bacteria play a role in the disease process.

OBJECTIVE

This pilot study aims to assess the longitudinal effect of corticosteroid therapy on sinus microbiota in chronic rhinosinusitis patients with nasal polyposis (CRSwNP).

METHODS

A longitudinal prospective case-control study was done on patients with CRSwNP and healthy controls. Patients with CRSwNP were randomly allocated to a corticosteroids and antibiotics treatment group (CRSwNP-SA) or a corticosteroid-only treatment group (CRSwNP-S). Data were collected at three-time points (before treatment, 1, and 3 months after treatment). Specimens were cultured and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) was used as a bacterial detection method.

RESULTS

Data from 29 patients with CRSwNP (16 CRSwNP-SA and 13 CRSwNP-S) was compared to 15 healthy subjects. Patients reported significant symptom improvement initially (1 month), but not in the long-term (3 months). This result was found in both treatment groups, whether or not antibiotics were used. After 3 months from treatment, the prevalence of Corynebacterium genera tended to increase in the CRSwNP-SA, while Staphylococcus and Gram-negative genera (Pseudomonas) tended to increase in the CRSwNP-S. Smoking, aspirin sensitivity, and previous endoscopic sinus surgery were found to be co-factors significantly associated with the response to systemic corticosteroid therapy.

CONCLUSION

In this pilot study, both treatment options were effective to improve symptoms in the short-term but not in the long-term, and were not linked to any clear sinus microbiota response. As a result, this study supports the avoidance of systemic antibiotics without evidence of active infection.

Effect of Chronic Rhinosinusitis on the Risk of Development of Rheumatoid Arthritis

PURPOSE

Several studies have reported a possible link between chronic rhinosinusitis (CRS) and rheumatoid arthritis (RA). However, it remains unclear whether CRS could influence the risk of developing RA. Therefore, in this study, we focused on examining the association between CRS and RA.

METHODS

A total of 14,867 individuals with CRS and 14,867 without CRS were enrolled after 1:1 propensity score match from a nationwide longitudinal cohort database in South Korea. RA incidence was assessed using person-years at risk, and the hazard ratio (HR) was examined using the Cox proportional hazards model.

RESULTS

The incidence of RA (per 1,000 person-years) was 6.51 for those with CRS, 6.55 for those with CRS without nasal polyps (CRSsNP), and 5.96 for those with CRS with nasal polyps (CRSwNP). We found that CRS individuals had a significantly increased risk of subsequent RA development with an adjusted HR of 1.41, regardless of the phenotype (adjusted HR was 1.42 in CRSsNP and 1.37 in CRSwNP patients). Moreover, the risk of developing RA over time was relatively higher within the first 4 years after the diagnosis of CRS.

CONCLUSIONS

Our nationwide population-based cohort study suggests that CRS may be associated with a subsequent increase in RA events, regardless of the phenotype. Therefore, physicians should consider RA risk when diagnosing and treating CRS patients.

Analysis of Sinus Inflammation Associated With Maxillary Sinus Fungal Ball Based on CT Imaging

Background: Paranasal sinus fungal balls usually occur unilaterally, and the maxillary sinus is most commonly involved. However, other sinuses could be concomitantly inflammed, and this phenomenon is rarely discussed. Aims/Objectives: To evaluate the severity of maxillary sinus fungal ball (MSFB) and the occurrence of sinus inflammation in paranasal sinuses according to the image findings and analyze the potential correlations. Material and Methods: A total of 1226 cases of MSFB were divided into 2 groups according to ostiomeatal complex obstruction on computed tomography. The potential correlations between sinus inflammation and MSFB in these groups were analyzed. Results: The patients were divided into 2 groups: those with obstructed ostiomeatal complex (OOMC) and those with clear ostiomeatal complex (COMC). The incidences of sinus inflammation in the ipsilateral sinuses of MSFB were higher in the OOMC group than in the COMC group, and there were no differences in the contralateral sinuses of MSFB. In the OOMC group, sinus inflammation was more common in all ipsilateral sinuses of MSFB than in the contralateral sinuses. In the COMC group, the incidences of sinus inflammation in the ipsilateral ethmoid and frontal sinuses of MSFB were higher than that in the contralateral sinuses. However, no significant difference was observed in the sinus inflammation incidence of bilateral sphenoid sinuses in the COMC group. The incidence of nasal polyps was higher in the ipsilateral nasal cavity in the OOMC group. Conclusions and Significance: MSFB stimulated sinus inflammation and nasal polyps in the adjacent sinuses through local factors.

Precision medicine in chronic rhinosinusitis - using endotype and endotype-driven therapeutic options

INTRODUCTION

Chronic rhinosinusitis (CRS) is a heterogeneous disease, and its complex pathophysiological characteristics pose a challenge to its clinical treatment. CRS is distinguished not only by clinical phenotype but also by endotype characteristics, which are divided into type 2 CRS and non-type 2 CRS.

AREAS COVERED

In this review, we summarize and discuss current studies that depict the mechanisms and endotypes of CRS. In particular, inflammatory cells and the microbiome play a role in the pathophysiology of CRS. We also listed some of the biomarkers described in recent studies that may serve as a theoretical foundation for additional investigations. We have summarized the advantages and disadvantages of existing treatments and listed the available biological treatments for CRS in detail.

EXPERT OPINION

Endotype-driven therapeutic options face many challenges because of the complexity of the disease. Glucocorticoids, nasal endoscopic surgery, and biological therapy are the main treatments used in clinical practice, but they have limitations. This review provides advice on the clinical management and treatment options for patients with different endotypes, which will be more conducive to improving the quality of life and reducing the financial burden on patients.

Assessment of the nasal microbiota in dogs with fungal rhinitis before and after cure and in dogs with chronic idiopathic rhinitis

BACKGROUND

Pathogenesis of canine fungal rhinitis is still not fully understood. Treatment remains challenging, after cure turbinate destruction may be associated with persistent clinical signs and recurrence of fungal rhinitis can occur. Alterations of the nasal microbiota have been demonstrated in dogs with chronic idiopathic rhinitis and nasal neoplasia, although whether they play a role in the pathogenesis or are a consequence of the disease is still unknown. The objectives of the present study were (1) to describe nasal microbiota alterations associated with fungal rhinitis in dogs, compared with chronic idiopathic rhinitis and controls, (2) to characterize the nasal microbiota modifications associated with successful treatment of fungal rhinitis. Forty dogs diagnosed with fungal rhinitis, 14 dogs with chronic idiopathic rhinitis and 29 healthy control dogs were included. Nine of the fungal rhinitis dogs were resampled after successful treatment with enilconazole infusion.

RESULTS

Only disease status contributed significantly to the variability of the microbiota. The relative abundance of the genus Moraxella was decreased in the fungal rhinitis (5.4 ± 18%) and chronic idiopathic rhinitis (4.6 ± 8.7%) groups compared to controls (51.8 ± 39.7%). Fungal rhinitis and chronic idiopathic rhinitis groups also showed an increased richness and α-diversity at species level compared with controls. Increase in unique families were associated with fungal rhinitis (Staphyloccaceae, Porphyromonadaceae, Enterobacteriaceae and Neisseriaceae) and chronic idiopathic rhinitis (Pasteurellaceae and Lactobacillaceae). In dogs with fungal rhinitis at cure, only 1 dog recovered a high relative abundance of Moraxellaceae.

CONCLUSIONS

Results confirm major alterations of the nasal microbiota in dogs affected with fungal rhinitis and chronic idiopathic rhinitis, consisting mainly in a decrease of Moraxella. Besides, a specific dysbiotic profile further differentiated fungal rhinitis from chronic idiopathic rhinitis. In dogs with fungal rhinitis, whether the NM returns to its pre-infection state or progresses toward chronic idiopathic rhinitis or fungal rhinitis recurrence warrants further investigation.

A Review on the Nasal Microbiome and Various Disease Conditions for Newer Approaches to Treatments

Introduction: Commensal bacteria have always played a significant role in the maintenance of health and disease but are being unravelled only recently. Studies suggest that the nasal microbiome has a significant role in the development of various disease conditions. Search engines were used for searching articles having a nasal microbiome and disease correlation. In olfactory dysfunction, dysbiosis of the microbiome may have a significant role to play in the pathogenesis. The nasal microbiome influences the phenotype of CRS and is also capable of modulating the immune response and plays a role in polyp formation. Microbiome dysbiosis has a pivotal role in the development of Allergic Rhinitis; but, yet known how is this role played. The nasal microbiome has a close association with the severity and phenotype of asthma. They contribute significantly to the onset, severity, and development of asthma. The nasal microbiome has a significant impact on the immunity and protection of its host. The nasal microbiome has been a stimulus in the development of Otitis Media and its manifestations. Studies suggest that the resident nasal microbiome is responsible for the initiation of neurodegenerative diseases like Parkinson's Disease.Materials and Methods: Literature search from PubMed, Medline, and Google with the Mesh terms: nasal microbiome AND diseases. Conclusion: With increasing evidence on the role of the nasal microbiome on various diseases, it would be interesting to see how this microbiome can be modulated by pro/pre/post biotics to prevent a disease or the severity of illness.

Microbiome and Th cytokines association in chronic rhinosinusitis with or without nasal polyp

Objective

Chronic rhinosinusitis (CRS), a common disease in otorhinolaryngology, seriously affects the life quality of patients. The existing therapy has certain limitations, and it is very urgent to deeply explore the pathogenesis and classification of CRS. Microbiome and inflammation are considered the causes of CRS, but the precise roles and the associations between these two factors in the pathogenesis of CRS remain controversial.

Methods

Secretions were collected from the middle nasal canal, maxillary sinus and ethmoid sinus in CRS patients, then subjected to 16 S rRNA gene sequencing to profile microbiota community. Operational Taxonomic Units clustering and species annotation were adopted to obtain species diversity, prevalence rate and average relative abundance. Comparisons were performed at the level of microbial species and genus between CRS and control using NMDS, Anosim and MetaStat analysis. Th1 cytokines and Th2 cytokines were detected by ELISA. Spearman analysis were adopted to probe into the correlation between Th cytokines and microbial species in CRS.

Results

Thirty-seven patients were enrolled, among them 22 with CRS and 15 were controls. The most abundant genera were Corynebacterium and Staphylococcus no matter in CRS patients or control. Corynebacterium propinquum was significant decreased in CRS patients no matter with nasal polyp or not. The abundances of Prevotella birria and Carnobacterium maltaromaticum were significantly different between CRSsNP and CRSwNP group. The levels of cytokines IL-2, TNF-α, IFN-ɣ, IL-4, IL-6, IL-10 were all increased in CRS patients. The cytokines levels were associated with specific microbial species in nasal tissue.

Conclusion

The changes of species richness and complexity in nasal microbiome were obvious in CRS patients with nasal polyps or not. The different cytokines levels and microbiome between CRS patients without nasal polyps and patients with nasal polyps suggest heterogeneity in pathogenesis of chronic rhinosinusitis. Distinct microbiota and different cytokines were strongly linked in CRS.

Level of Evidence

NA.

Associations of Microbial Diversity with Age and Other Clinical Variables among Pediatric Chronic Rhinosinusitis (CRS) Patients

Chronic rhinosinusitis (CRS) is a heterogenous disease that causes persistent paranasal sinus inflammation in children. Microorganisms are thought to contribute to the etiology and progression of CRS. Culture-independent microbiome analysis offers deeper insights into sinonasal microbial diversity and microbe-disease associations than culture-based methods. To date, CRS-related microbiome studies have mostly focused on the adult population, and only one study has characterized the pediatric CRS microbiome. In this study, we analyzed the bacterial diversity of adenoid tissue, adenoid swab, maxillary sinus, and sinus wash samples from 45 pediatric CRS patients recruited from the Johns Hopkins All Children's Hospital (JHACH) in St. Petersburg, FL, USA. The alpha diversity in these samples was associated with baseline nasal steroid use, leukotriene receptor antagonist (LTRA) use, and total serum immunoglobulin (Ig) E (IgE) level. Streptococcus, Moraxella, and Haemophilus spp. were most frequently identified from sinus cultures and the sequenced 16S rRNA gene content. Comparative analyses combining our samples with the samples from the previous microbiome study revealed differentially abundant genera between patients with pediatric CRS and healthy controls, including Cutibacterium and Moraxella. Additionally, the abundances of Streptobacillus and Staphylococcus were consistently correlated with age in both adenoid- and sinus-derived samples. Our study uncovers new associations of alpha diversity with clinical parameters, as well as associations of specific genera with disease status and age, that can be further investigated.

Exacerbation of allergic rhinitis by the commensal bacterium Streptococcus salivarius

Allergic rhinitis (AR)-commonly called hay fever-is a widespread condition that affects the quality of life of millions of people. The pathophysiology of AR remains incompletely understood. In particular, it is unclear whether members of the colonizing nasal microbiota contribute to AR. Here, using 16S ribosomal RNA sequencing, we show that the nasal microbiome of patients with AR (n = 55) shows distinct differences compared with that from healthy individuals (n = 105), including decreased heterogeneity and the increased abundance of one species, Streptococcus salivarius. Using ex vivo and in vivo models of AR, we demonstrate that this commensal bacterium contributes to AR development, promoting inflammatory cytokine release and morphological changes in the nasal epithelium that are characteristic of AR. Our data indicate that this is due to the ability of S. salivarius to adhere to the nasal epithelium under AR conditions. Our study indicates the potential of targeted antibacterial approaches for AR therapy.

Local allergic rhinitis: considerations

The term "local allergic rhinitis" has gained popularity as a clinical entity in recent years. Despite the apparent contradiction in the definitions of "nasal" and "local," we offer insights based on our extensive experience in the field. Local allergic rhinitis has been recognized and treated for many years, so it is not a new discovery. The nasal provocation test, which was introduced in the 1980s, was critical in identifying allergic rhinitis cases with suggestive symptoms but negative allergy tests. Our reflections aim to contribute to a precise terminological decision that is consistent with various points of view.

Microbiota dysbiosis in odontogenic rhinosinusitis and its association with anaerobic bacteria

Odontogenic rhinosinusitis is a subtype of rhinosinusitis associated with dental infection or dental procedures and has special bacteriologic features. Previous research on the bacteriologic features of odontogenic rhinosinusitis has mainly used culture-dependent methods. The variation of microbiota between odontogenic and nonodontogenic rhinosinusitis as well as the interplay between the involved bacteria have not been explored. Therefore, we enrolled eight odontogenic rhinosinusitis cases and twenty nonodontogenic rhinosinusitis cases to analyze bacterial microbiota through 16S rRNA sequencing. Significant differences were revealed by the Shannon diversity index (Wilcoxon test p = 0.0003) and PERMANOVA test based on weighted UniFrac distance (Wilcoxon test p = 0.001) between odontogenic and nonodontogenic samples. Anaerobic bacteria such as Porphyromonas, Fusobacterium, and Prevotella were significantly dominant in the odontogenic rhinosinusitis group. Remarkably, a correlation between different bacteria was also revealed by Pearson's correlation. Staphylococcus was highly positively associated with Corynebacterium, whereas Fusobacterium was highly negatively correlated with Prophyromonas. According to our results, the microbiota in odontogenic rhinosinusitis, predominantly anaerobic bacteria, was significantly different from that in nonodontogenic rhinosinusitis, and the interplay between specific bacteria may a major cause of this subtype of rhinosinusitis.

Low Diversity and Instability of the Sinus Microbiota over Time in Adults with Cystic Fibrosis

Chronic rhinosinusitis (CRS) is a common, yet underreported and understudied manifestation of upper respiratory disease in people with cystic fibrosis (CF). Recently developed standard of care guidelines for the management of CF CRS suggest treatment of upper airway disease may ameliorate lower airway disease. We sought to determine whether changes to sinus microbial community diversity and specific taxa known to cause CF lung disease are associated with increased respiratory disease and inflammation. We performed 16S rRNA gene sequencing, supplemented with cytokine analyses, microscopy, and bacterial culturing, on samples from the sinuses of 27 adults with CF CRS. At each study visit, participants underwent endoscopic paranasal sinus sampling and clinical evaluation. We identified key drivers of microbial community composition and evaluated relationships between diversity and taxa with disease outcomes and inflammation. Sinus community diversity was low, and the composition was unstable, with many participants exhibiting alternating dominance between Pseudomonas aeruginosa and staphylococci over time. Despite a tendency for dominance by these two taxa, communities were highly individualized and shifted composition during exacerbation of sinus disease symptoms. Exacerbations were also associated with communities dominated by Staphylococcus spp. Reduced microbial community diversity was linked to worse sinus disease and the inflammatory status of the sinuses (including increased interleukin-1β [IL-1β]). Increased IL-1β was also linked to worse sinus endoscopic appearance, and other cytokines were linked to microbial community dynamics. Our work revealed previously unknown instability of sinus microbial communities and a link between inflammation, lack of microbial community diversity, and worse sinus disease. IMPORTANCE Together with prior sinus microbiota studies of adults with CF chronic rhinosinusitis, our study underscores similarities between sinus and lower respiratory tract microbial community structures in CF. We show how community structure tracks with inflammation and several disease measures. This work strongly suggests that clinical management of CRS could be leveraged to improve overall respiratory health in CF. Our work implicates elevated IL-1β in reduced microbiota diversity and worse sinus disease in CF CRS, suggesting applications for existing therapies targeting IL-1β. Finally, the widespread use of highly effective cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy has led to less frequent availability of spontaneous expectorated sputum for microbiological surveillance of lung infections. A better understanding of CF sinus microbiology could provide a much-needed alternative site for monitoring respiratory infection status by important CF pathogens.

The Changes in Bacterial Microbiome Associated with Immune Disorder in Allergic Respiratory Disease

Allergic respiratory disease is a worldwide and increasingly prevalent health problem. Many researchers have identified complex changes in the microbiota of the respiratory and intestinal tracts in patients with allergic respiratory diseases. These affect immune response and influence the progression of disease. However, the diversity of bacterial changes in such cases make it difficult to identify a specific microorganism to target for adjustment. Recent research evidence suggests that common bacterial variations present in allergic respiratory disease are associated with immune disorders. This finding could lead to the discovery of potential therapeutic targets in cases of allergic respiratory disease. In this review, we summarize current knowledge of bacteria changes in cases of allergic respiratory disease, to identify changes commonly associated with immune disorders, and thus provide a theoretical basis for targeting therapies of allergic respiratory disease through effective modulation of key bacteria.

Topical Antibiofilm Agents With Potential Utility in the Treatment of Chronic Rhinosinusitis: A Narrative Review

The role of bacterial biofilms in chronic and recalcitrant diseases is widely appreciated, and the treatment of biofilm infection is an increasingly important area of research. Chronic rhinosinusitis (CRS) is a complex disease associated with sinonasal dysbiosis and the presence of bacterial biofilms. While most biofilm-related diseases are associated with highly persistent but relatively less severe inflammation, the presence of biofilms in CRS is associated with greater severity of inflammation and recalcitrance despite appropriate treatment. Oral antibiotics are commonly used to treat CRS but they are often ineffective, due to poor penetration of the sinonasal mucosa and the inherently antibiotic resistant nature of bacteria in biofilms. Topical non-antibiotic antibiofilm agents may prove more effective, but few such agents are available for sinonasal application. We review compounds with antibiofilm activity that may be useful for treating biofilm-associated CRS, including halogen-based compounds, quaternary ammonium compounds and derivatives, biguanides, antimicrobial peptides, chelating agents and natural products. These include preparations that are currently available and those still in development. For each compound, antibiofilm efficacy, mechanism of action, and toxicity as it relates to sinonasal application are summarised. We highlight the antibiofilm agents that we believe hold the greatest promise for the treatment of biofilm-associated CRS in order to inform future research on the management of this difficult condition.

The histological and microbiological characteristics of bacterial microcolonies in paediatric tonsillar hyperplasia

INTRODUCTION

Paediatric tonsillar hyperplasia (TH) is associated with a spectrum of presentations ranging from recurrent tonsillitis (RT) to sleep-disordered breathing (SDB). The underlying pathogenesis of tonsillar hyperplasia remains poorly understood. Previous studies have implicated bacterial microcolonies as targets of host inflammatory cells and as a potential driver of the chronic inflammation seen in TH. The role of atopy in tonsillar hyperplasia is also largely unknown. In this study, we aimed to determine the allergic responses and microbial factors that may influence TH in children.

MATERIALS AND METHODS

Paired tonsils and a serum sample were collected from 21 children undergoing tonsillectomy for RT or SDB in the Auckland region. The disposition of immunoglobulin isotypes (IgG, A, M and E) and local inflammatory cells on histological sections of tonsil tissue were determined using immunohistochemistry techniques. Aeroallergen specific IgE (sIgE) and Staphylococcal enterotoxin C specific IgE (SEC-specific IgE) were measured in serum and tonsil tissue using the ImmunoCAP® system. Finally, tonsil bacterial microcolonies were then excised from histological slides using laser microdissection techniques, before undergoing bacterial and fungal amplicon sequencing.

RESULTS

There were no significant differences in any of the measured variables between children with RT and SDB symptoms. IgE staining was not associated with increased levels of mast cells, leukocytes or plasma cells. However, sIgE positivity was more frequently found in local tissue than in serum (p = 0.025). A significant association was observed between tissue sIgE levels and tissue SEC-specific IgE levels (r² = 0.95, p = 0.0001). The most abundant bacterial and fungal genera identified in the microcolonies were Fusobacterium, Sphingomonas, Porphyromonas, Prevotella and Malassezia.

DISCUSSION

These results suggest that there is a local IgE response in children with TH. Local IgE production is unrelated to systemic atopy and may play a key role in the pathogenesis of TH. This is the first study to determine the microbial composition of microcolonies in tonsil tissue. These findings enhance current understanding of the microbiology of tonsils in children with TH and have important implications for antibiotic strategies.

Review: The Nose as a Route for Therapy. Part 2 Immunotherapy

The nose provides a route of access to the body for inhalants and fluids. Unsurprisingly it has a strong immune defense system, with involvement of innate (e.g., epithelial barrier, muco- ciliary clearance, nasal secretions with interferons, lysozyme, nitric oxide) and acquired (e.g., secreted immunoglobulins, lymphocytes) arms. The lattice network of dendritic cells surrounding the nostrils allows rapid uptake and sampling of molecules able to negotiate the epithelial barrier. Despite this many respiratory infections, including SARS-CoV2, are initiated through nasal mucosal contact, and the nasal mucosa is a significant "reservoir" for microbes including Streptococcus pneumoniae, Neisseria meningitidis and SARS -CoV-2. This review includes consideration of the augmentation of immune defense by the nasal application of interferons, then the reduction of unnecessary inflammation and infection by alteration of the nasal microbiome. The nasal mucosa and associated lymphoid tissue (nasopharynx-associated lymphoid tissue, NALT) provides an important site for vaccine delivery, with cold-adapted live influenza strains (LAIV), which replicate intranasally, resulting in an immune response without significant clinical symptoms, being the most successful thus far. Finally, the clever intranasal application of antibodies bispecific for allergens and Intercellular Adhesion Molecule 1 (ICAM-1) as a topical treatment for allergic and RV-induced rhinitis is explained.

Staphylococcus aureus Overcomes Anaerobe-Derived Short-Chain Fatty Acid Stress via FadX and the CodY Regulon

Chronic rhinosinusitis (CRS) is characterized by immune dysfunction, mucus hypersecretion, and persistent infection of the paranasal sinuses. While Staphylococcus aureus is a primary CRS pathogen, recent sequence-based surveys have found increased relative abundances of anaerobic bacteria, suggesting that S. aureus may experience altered metabolic landscapes in CRS relative to healthy airways. To test this possibility, we characterized the growth kinetics and transcriptome of S. aureus in supernatants of the abundant CRS anaerobe Fusobacterium nucleatum. While growth was initially delayed, S. aureus ultimately grew to similar levels as in the control medium. The transcriptome was significantly affected by F. nucleatum metabolites, with the agr quorum sensing system notably repressed. Conversely, expression of fadX, encoding a putative propionate coenzyme A (CoA)-transferase, was significantly increased, leading to our hypothesis that short-chain fatty acids (SCFAs) produced by F. nucleatum could mediate S. aureus growth behavior and gene expression. Supplementation with propionate and butyrate, but not acetate, recapitulated delayed growth phenotypes observed in F. nucleatum supernatants. A fadX mutant was found to be more sensitive than wild type to propionate, suggesting a role for FadX in the S. aureus SCFA stress response. Interestingly, spontaneous resistance to butyrate, but not propionate, was observed frequently. Whole-genome sequencing and targeted mutagenesis identified codY mutants as resistant to butyrate inhibition. Together, these data show that S. aureus physiology is dependent on its cocolonizing microbiota and metabolites they exchange and indicate that propionate and butyrate may act on different targets in S. aureus to suppress its growth. IMPORTANCE Staphylococcus aureus is an important CRS pathogen, and yet it is found in the upper airways of 30% to 50% of people without complications. The presence of strict and facultative anaerobic bacteria in CRS sinuses has recently spurred research into bacterial interactions and how they influence S. aureus physiology and pathogenesis. We show here that propionate and butyrate produced by one such CRS anaerobe, namely, Fusobacterium nucleatum, alter the growth and gene expression of S. aureus. We show that fadX is important for S. aureus to resist propionate stress and that the CodY regulon mediates growth in inhibitory concentrations of butyrate. This work highlights the possible complexity of S. aureus-anaerobe interactions and implicates membrane stress as a possible mechanism influencing S. aureus behavior in CRS sinuses.

Unravelling the role of the microbiome in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a complex, heterogenous condition with likely infectious and inflammatory causative factors. Renewed interest in the role that microbes play in this condition has stemmed from advancements in microbe identification and parallel research that has implicated the role of the microbiome in other chronic inflammatory conditions. This clinical commentary provides a review of the current literature relevant to chronic rhinosinusitis. Particular focus is paid to factors specific to the investigation of the sinonasal microbiome, evidence for the role of dysbiosis in the disease state and influences that may impact the microbiome. Possible mechanisms of disease and therapeutic implications through microbial manipulation are also reviewed, as are deficiencies and limitations of the current body of research.

In vitro and in vivo evaluation of probiotic properties of Corynebacterium accolens isolated from the human nasal cavity

Corynebacterium accolens strains are increasingly recognized as beneficial bacteria that can confer a health benefit on the host. In the current study, the probiotic potential of three C. accolens strains, C779, C781 and C787 derived from a healthy human nasal cavity were investigated. These strains were examined for their adhesion to HNECs, competition with Staphylococcus aureus for adhesion, toxicity, induction of IL-6, antibiotic susceptibility and the presence of antibiotic resistance and virulence genes. Furthermore, the safety and efficacy of strains were evaluated in vivo using Caenorhabditis elegans. The adhesion capacity of C. accolens to HNECs was strain-dependent. Highest adhesion was observed for strain C781. None of the C. accolens strains tested caused cell lysis. All strains were able to outcompete S. aureus for cell adhesion and caused a significant decrease of IL-6 production by HNECs co-exposed to S. aureus when compared to the control groups. All strains were sensitive or showed intermediate sensitivity to 10 different antibiotics. Whole Genome Sequence analysis showed C. accolens C781 and C787 did not possess antibiotic resistance genes whereas strain C779 harboured 5 genes associated with resistance to Aminoglycoside, Chloramphenicol and Erythromycin. In addition, no virulence genes were detected in any of the 3 strains. Moreover, the tested strains had no detrimental effect on worm survival and induced protection from S. aureus-mediated infection. Taken all together, C. accolens strains, C781 and C787 displayed probiotic potential and hold promise for use in clinical applications for combating dysbiosis in chronic rhinosinusitis.

Characterising clinical Staphylococcus aureus isolates from the sinuses of patients with chronic rhinosinusitis

The role of Staphylococcus aureus in the pathogenesis of the chronic sinonasal disease chronic rhinosinusitis (CRS), has not been definitively established. Comparative analyses of S. aureus isolates from CRS with those from control participants may offer insight into a possible pathogenic link between this organism and CRS. The intra- and inter-subject S. aureus strain-level diversity in the sinuses of patients with and without CRS were compared in this cross-sectional study. In total, 100 patients (CRS = 64, control = 36) were screened for S. aureus carriage. The overall carriage prevalence of S. aureus in this cohort was 24% (CRS n = 13, control n = 11). Cultured S. aureus isolates from 18 participants were strain-typed using spa gene sequencing. The bacterial community composition of the middle meatus was assessed using amplicon sequencing targeting the V3V4 hypervariable region of the bacterial 16S rRNA gene. S. aureus isolates cultured from patients were grown in co-culture with the commensal bacterium Dolosigranulum pigrum and characterised. All participants harboured a single S. aureus strain and no trend in disease-specific strain-level diversity was observed. Bacterial community analyses revealed a significant negative correlation in the relative abundances of S. aureus and D. pigrum sequences, suggesting an antagonistic interaction between these organisms. Co-cultivation experiments with these bacteria, however, did not confirm this interaction in vitro. We saw no significant associations of CRS disease with S. aureus strain types. The functional role that S. aureus occupies in CRS likely depends on other factors such as variations in gene expression and interactions with other members of the sinus bacterial community.

Associations of air pollution and greenness with the nasal microbiota of healthy infants: A longitudinal study

BACKGROUND

Air pollution and greenness are associated with short- and long-term respiratory health in children but the underlying mechanisms are only scarcely investigated. The nasal microbiota during the first year of life has been shown to be associated with respiratory tract infections and asthma development. Thus, an interplay between greenness, air pollution and the early nasal microbiota may contribute to short- and long-term respiratory health. We aimed to examine associations between fine particulate matter (PM_2.5), nitrogen dioxide (NO₂) and greenness with the nasal microbiota of healthy infants during the first year of life in a European context with low-to-moderate air pollution levels.

METHODS

Microbiota characterization was performed using 16 S rRNA pyrosequencing of 846 nasal swabs collected fortnightly from 47 healthy infants of the prospective Basel-Bern Infant Lung Development (BILD) cohort. We investigated the association of satellite-based greenness and an 8-day-average exposure to air pollution (PM_2.5, NO₂) with the nasal microbiota during the first year of life. Exposures were individually estimated with novel spatial-temporal models incorporating satellite data. Generalized additive mixed models adjusted for known confounders and considering the autoregressive correlation structure of the data were used for analysis.

RESULTS

Mean (SD) PM_2.5 level was 17.1 (3.8 μg/m³) and mean (SD) NO₂ level was 19.7 (7.9 μg/m³). Increased PM_2.5 and increased NO₂ were associated with reduced within-subject Ružička dissimilarity (PM_2.5: per 1 μg/m³ -0.004, 95% CI -0.008, -0.001; NO₂: per 1 μg/m³ -0.004, 95% CI -0.007, -0.001). Whole microbial community comparison with nonmetric multidimensional scaling revealed distinct microbiota profiles for different PM_2.5 exposure levels. Increased NO₂ was additionally associated with reduced abundance of Corynebacteriaceae (per 1 μg/m³: -0.027, 95% CI -0.053, -0.001). No associations were found between greenness and the nasal microbiota.

CONCLUSION

Air pollution was associated with Ružička dissimilarity and relative abundance of Corynebacteriaceae. This suggests that even low-to-moderate exposure to air pollution may impact the nasal microbiota during the first year of life. Our results will be useful for future studies assessing the clinical relevance of air-pollution-induced alterations of the nasal microbiota with subsequent respiratory disease development.

Unilateral Intervention in the Sinuses of Rabbits Induces Bilateral Inflammatory and Microbial Changes

Background

Chronic rhinosinusitis (CRS) is a globally prevalent inflammatory condition of the paranasal sinuses which severely impairs patients' quality of life. An animal model of unilateral sinusitis by transient sinus occlusion has been described previously in rabbits. The aim of this study was to characterise the sinusitis rabbit model by investigating temporal and bilateral changes in the bacterial community and mucosal inflammation.

Methods

Development of sinusitis was achieved by endoscopically placing Merocel ^® , a sterile nasal packing material, in the left middle meatus of six New Zealand white rabbits for four weeks. After a total period of 14 weeks, rabbits were assessed for sinusitis by endoscopic examination, magnetic resonance imaging (MRI) and histology. Swabs from the left and right middle meatus were obtained for bacterial community analysis at three time points (week 0, week 4, week 14) during the study.

Results

Endoscopic evaluation showed unilateral inflammation in all animals examined after the 4-week blocking period and at week 14. Notably, inflammatory changes were also seen in the contralateral sinus of all animals at week 4. MRI images demonstrated unilateral sinus opacification at week 4 in two rabbits, and partial unilateral sinus opacification at week 14 in one rabbit only. Histological analyses revealed substantial spatial heterogeneity of mucosal inflammation with inconsistent findings across all animals. No significant differences in mucosal inflammatory markers (such as goblet cell hyperplasia, epithelial denudation and oedema) could be identified between nostrils at week 14. The bacterial community in the rabbit sinuses was heavily dominated by Helicobacter at week 0 (baseline). At the end of the blocking period (week 4), bacterial alpha and beta diversity were significantly increased in both nostrils. The bacterial community composition at week 14 had primarily returned to baseline, reflecting the endoscopic and radiological results.

Conclusion

This study reaffirmed the ability for development of sinusitis without inoculation of any pathogens in a rabbit model. We were able to demonstrate bilateral sinonasal mucosal inflammation, by inducing unilateral sinus blockage, which resulted in significant changes to the sinonasal bacterial community. These findings may explain some of the clinical observations seen in CRS and warrant further research to reveal potential implications for its therapeutic management.

Microbiome of Unilateral Chronic Rhinosinusitis: A Controlled Paired Analysis

The sinonasal microbiota in human upper airway may play an important role in chronic rhinosinusitis (CRS). Thus, this study aimed to investigate the human upper airway microbiome in patients with unilateral CRS, and compare the sinonasal microbiome of the unilateral diseased site with that of a contralateral healthy site. Thirty samples, 15 each from the diseased and healthy sites, were collected from the middle meatus and/or anterior ethmoid region of 15 patients with unilateral CRS during endoscopic sinus surgery. DNA extraction and bacterial microbiome analysis via 16S rRNA gene sequencing were then performed. Corynebacterium showed the highest relative abundance, followed by Staphylococcus in samples from both the diseased and healthy sites. Further, the relative abundances of Staphylococcus and Pseudomonas were significantly lower in samples from diseased sites than in those from healthy sites. Conversely, anaerobes, including Fusobacterium, Bacteroides, and Propionibacterium, were abundantly present in samples from both sites, more so in samples from diseased sites. However, the sites showed no significant difference with respect to richness or diversity (p > 0.05). Our results indicate that CRS might be a polymicrobial infection, and also suggest that Corynebacterium and Staphylococcus may exist as commensals on the sinus mucosal surface in the upper respiratory tract.

Sinus Microbiota in Patients With Eosinophilic and Non-Eosinophilic Chronic Rhinosinusitis With Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2-skewed inflammation and increased colonization by Staphylococcus aureus. CRSwNP can be distinguished as eosinophilic (ECRSwNP) and non-eosinophilic (NECRSwNP) by the infiltration of eosinophils. The local microbiota plays an important role in the persistent inflammation of CRSwNP. To evaluate the bacterial community composition on the distinct types of CRSwNP patients, we collected nasal swabs from 16 ECRSwNP patients, 18 NECRSwNP patients, and 39 healthy control subjects. The microbiome structure for all the samples were analyzed by high-throughput 16S rRNA gene sequencing. Concentration of S. aureus was determined using TaqMan quantitative polymerase chain reaction (qPCR) targeting the nuclease (nuc) gene. The result showed significant differences in the sinus microbiome among healthy control subjects and CRSwNP patients. Microbiota community diversity was significantly lower in NECRSwNP samples compared to that of healthy control subjects. Interestingly, the abundance of several pathogenic bacteria was diverse between ECRSwNP and NECRSwNP patients. Although Staphylococcus prevailed in all groups, the abundance of Staphylococcus was significantly higher in the healthy control group than the ECRSwNP group. More importantly, the abundance of S. aureus was much higher in NECRSwNP patients. This study highlights that microbiota composition may contribute to the different clinical types of CRSwNP, inspiring new therapeutic strategies to resolve this chronic inflammation process.

Antibiotic-Dependent Relationships Between the Nasal Microbiome and Secreted Proteome in Nasal Polyps

PURPOSE

Chronic rhinosinusitis (CRS) is a heterogeneous chronic inflammatory condition of the paranasal sinuses and nasal passages. Although antibiotics are used to reduce inflammation or to treat an episode of acute rhinosinusitis, their effects on the nasal environment and host response in CRS is unclear.

METHODS

We analyzed the effects of antibiotics on the nasal microbiome and secreted proteome in CRS using multi-omic analysis. Nasal secretions were collected from 29 controls, 30 CRS patients without nasal polyps (NP), and 40 CRS patients with NP. A total of 99 subjects were divided into 2 groups that included subjects who had taken antibiotics 3 months prior to sampling and those who had not. We performed 16S ribosomal DNA sequence analyses and Orbitrap mass spectrometry-based proteomic analyses. Spearman correlation was used to assess the correlations between the nasal microbiome and secreted proteome.

RESULTS

The associations between the nasal microbiome and secreted proteome were noted in subjects who had used antibiotics. Antibiotics could have stronger effects on their associations in patients with CRS with NP than in those without. It remains unknown whether these holistic changes caused by antibiotics are beneficial or harmful to CRS, however, the associations could be differentially affected by disease severity.

CONCLUSION

These findings provide new insight into the nasal environment and the host response in CRS.

Cross-correlation of virome-bacteriome-host-metabolome to study respiratory health

A comprehensive understanding of the microbiome-host relationship in respiratory diseases can be elucidated by exploring the landscape of virome-bacteriome-host metabolome data through unsupervised 'multi-omics' approaches. Here, we describe how the composition and function of airway and gut virome and bacteriome may contribute to pathogen establishment and propagation in airway districts and how the virome-bacteriome communities may react to respiratory diseases. A new systems medicine approach, including the characterization of respiratory and gut microbiome, may be crucial to demonstrate the likelihood and odds of respiratory disease pathophysiology, opening new avenues to the discovery of a chain of causation for key bacteria and viruses in disease severity.

Lactobacilli Have a Niche in the Human Nose

Although an increasing number of beneficial microbiome members are characterized for the human gut and vagina, beneficial microbes are underexplored for the human upper respiratory tract (URT). In this study, we demonstrate that taxa from the beneficial Lactobacillus genus complex are more prevalent in the healthy URT than in patients with chronic rhinosinusitis (CRS). Several URT-specific isolates are cultured, characterized, and further explored for their genetic and functional properties related to adaptation to the URT. Catalase genes are found in the identified lactobacilli, which is a unique feature within this mostly facultative anaerobic genus. Moreover, one of our isolated strains, Lactobacillus casei AMBR2, contains fimbriae that enable strong adherence to URT epithelium, inhibit the growth and virulence of several URT pathogens, and successfully colonize nasal epithelium of healthy volunteers. This study thus demonstrates that specific lactobacilli are adapted to the URT and could have a beneficial keystone function in this habitat.

A scoping review of longitudinal airway microbiota studies

INTRODUCTION

The role of the microbiota in inflammatory airway diseases is unclear. Antimicrobial therapies have predominantly been guided by culture results. However, molecular sequencing has shown that the airway microbiota is much more complex and accurate modeling requires longitudinal analysis.

AREAS COVERED

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses scoping review was performed by searching Medline, Scopus, and Web of Science databases for all longitudinal airway microbiota studies that utilized molecular techniques. 38 studies with 1,993 participants were included in this review. Healthy microbial communities were more diverse, individualized and stable over time. Acute infections resulted in changes in the microbiota that were detected earlier and more sensitively by molecular sequencing than culture. Distinct microbiota profiles have been demonstrated in chronic obstructive pulmonary disease patients associated with exacerbation frequency and severity.

EXPERT OPINION

Longitudinal studies provide essential data on the stability of the microbiota over time and valuable information about the dynamic interactions between host, disease and microbes. We believe that molecular sequencing will be increasingly incorporated into research and clinical practice in the future. These advances can lead to improved diagnosis, enhanced prescribing guidance and reduce unnecessary antibiotic usage.

Association Between Microbiota and Nasal Mucosal Diseases in terms of Immunity

The pathogenesis of nasal inflammatory diseases is related to various factors such as anatomical structure, heredity, and environment. The nasal microbiota play a key role in coordinating immune system functions. Dysfunction of the microbiota has a significant impact on the occurrence and development of nasal inflammation. This review will introduce the positive and negative roles of microbiota involved in immunity surrounding nasal mucosal diseases such as chronic sinusitis and allergic rhinitis. In addition, we will also introduce recent developments in DNA sequencing, metabolomics, and proteomics combined with computation-based bioinformatics.

Sinonasal and gastrointestinal bacterial composition and abundance are stable after 1 week of once-daily oral antibiotic treatment for chronic rhinosinusitis

BACKGROUND

Despite the widespread prescription of antibiotics for the treatment of chronic rhinosinusitis (CRS), their efficacy remains uncertain. Limited penetration of systemic antibiotics into the sinonasal mucosa has been reported previously by this group. This study aimed to investigate the short-term effects of antibiotics on the sinus and gut microbiota as well as any relationships these had with drug distribution.

METHODS

Thirty subjects undergoing functional endoscopic sinus surgery for CRS were randomized to one of three groups: (1) doxycycline (100 mg daily for 7 days); (2) roxithromycin (300 mg daily for 7 days); and (3) control (no antibiotics given). Sinonasal and stool samples collected before and after treatment were analyzed using 16S ribosomal RNA (rRNA) gene-targeted amplicon sequencing and Droplet Digital polymerase chain reaction (PCR) for bacterial community composition and the quantification of bacterial DNA, respectively.

RESULTS

There were no significant major bacterial community shifts or changes to bacterial diversity and load following the treatment period in all patient groups. Non-significant trend reductions were observed in gut microbial diversity with antibiotics. For the roxithromycin group, sinonasal bacterial diversity was negatively correlated with serum drug levels and reduced overall compared to controls (p < 0.05). The relative abundance of Staphylococcus ASV129 in sinonasal samples reduced with increasing mucus doxycycline levels (p = 0.01).

CONCLUSION

Antibiotic prescription for CRS should be further investigated because of preliminary evidence of poor sinonasal drug penetration, unproven efficacy, and the potential impact of dysbiosis in the sinuses and off-target sites. Further studies should consider distinguishing the presence of DNA from viable and nonviable bacteria.

Longitudinal analysis of sinus microbiota post endoscopic surgery in patients with cystic fibrosis and chronic rhinosinusitis: a pilot study

BACKGROUND

Cystic fibrosis is a debilitating, autosomal recessive disease which results in chronic upper and lower airway infection and inflammation. In this study, four adult patients presenting with cystic fibrosis and chronic rhinosinusitis were recruited. Culture and molecular techniques were employed to evaluate changes in microbial profiles, host gene expression and antimicrobial resistance (AMR) in the upper respiratory tract over time.

METHODS

Swab samples from the sinonasal cavity were collected at the time of surgery and at follow-up clinics at regular time intervals for up to 18 months. Nucleic acids were extracted, and DNA amplicon sequencing was applied to describe bacterial and fungal composition. In parallel, RNA was used to evaluate the expression of 17 AMR genes and two inflammatory markers (interleukins 6 and 8) using custom qPCR array cards. Molecular results were compared with routine sinus and sputum culture reports within each patient.

RESULTS

Bacterial amplicon sequencing and swab culture reports from the sinonasal cavity were mostly congruent and relatively stable for each patient across time. The predominant species detected in patients P02 and P04 were Pseudomonas aeruginosa, Staphylococcus aureus in patient P03, and a mixture of Enterobacter and S. aureus in patient P01. Fungal profiles were variable and less subject specific than bacterial communities. Increased expressions of interleukins 6 and 8 were observed in all patients throughout the sampling period compared with other measured genes. The most prevalent AMR gene detected was ampC. However, the prevalence of AMR gene expression was low in all patient samples across varying time-points.

CONCLUSIONS

We observed a surprising degree of stability of sinonasal microbial composition, and inflammatory and AMR gene expression across all patients post sinus surgery.

Postoperative Infection Rate and Associated Factors Following Endoscopic Sinus Surgery

OBJECTIVES

There is a paucity of data on postoperative infections after endoscopic sinus surgery and associated risk factors. Our objective was to evaluate a cohort of patients undergoing endoscopic sinus surgery (ESS) for chronic rhinosinusitis to determine which perioperative factors may be associated with infection in the 30-day postoperative period.

METHODS

A retrospective cohort study of adults who underwent ESS at a tertiary academic medical center from 2015 to 2018 was performed. The primary outcome was incidence of postoperative infection, defined by identification of sinus purulence on nasal endoscopy necessitating antibiotics within 30 days of surgery. Independent variables collated included the result of postoperative cultures and use of perioperative antibiotics, oral corticosteroids, packing, and steroid-eluting stents. Statistical analysis involved bivariate analysis to identify variables that correlated with postoperative infection and subsequent multivariate logistic regression to identify independent risk factors.

RESULTS

Three hundred seventy-eight unique ESS cases performed in 356 patients were reviewed. The mean age was 46 years (range, 18-87). The most common indication for surgery was chronic rhinosinusitis without nasal polyposis. The postoperative infection rate was 10.1%. The most commonly cultured pathogen was Staphylococcus aureus. Multivariate logistic regression analysis showed that postoperative systemic corticosteroid use was the only risk factor independently associated with infection (OR 3.47 [95% CI 1.23-9.76], P = .018).

CONCLUSION

The incidence of postoperative infection following ESS was 10.1%. The use of postoperative systemic corticosteroids independently increased the risk of infection by 3.47-fold.

The influence of nasal microbiome diversity and inflammatory patterns on the prognosis of nasal polyps

To understand the inflammatory microenvironment and microbiome factors for prognosis of chronic rhinosinusitis with polyps (CRSwNP), we explored the difference in characteristics of the microbiome of the nasal sinuses and inflammatory cytokines between recurrent and non-recurrent groups. We collected nasal secretions and polyp tissue from 77 CRSwNP patients. Then, we extracted microbial DNA from cotton swabs, performed high-throughput sequencing based on 16S rRNA to detect bacterial community composition, and analyzed cytokines such as IL-5, IL-8, IL-17a, IL-17e, IL-18, IL-27 and INF-gamma from polyp tissue using Luminex. The eosinophil and neutrophil cells in the peripheral blood and polyp tissue were counted. Postoperative follow-up of patients with CRSwNP for 1 year was conducted to record the recurrence of nasal polyps and analyze the correlation between the recurrence of nasal polyps and the characteristics of inflammatory cytokines, inflammatory cell count and nasal microbial diversity. After 1 year of follow-up, there were 12 recurrent patients, including 5 males and 7 females. Postoperative recurrence of nasal polyps was not significantly correlated with age, sex, asthma, allergic rhinitis or other allergic diseases in CRSwNP patients. In terms of the total nasal symptom score, the recurrent group was significantly higher than the non-recurrent group. In nasal polyp tissues, eosinophils (40.83/HP) and neutrophils (30.83/HP) in patients with CRSwNP in the recurrent group were significantly higher than those in the non-recurrent group (13.72/HP), and neutrophils (18.5/HP) were also significantly higher in the recurrent group than the non-recurrent group. The expression levels of IFN-, IL-17A, IL-17E and IL-18 were significantly higher in the recurrent group than in the non-recurrent group, and the positive rates were not different. In Southwest China, Enterobacteria and anaerobic bacteria may be correlated with the inflammatory pattern expression of nasal polyps. The neutrophil-mediated inflammatory response plays an important role in patients with CRSwNP in Southwest China and is correlated with nasal polyp recurrence. Recurrence of nasal polyps after endoscopic sinus surgery may be potentially associated with a reduced abundance of protective microorganisms and an increased number of pathogenic microorganisms.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Corynebacterium accolens Has Antimicrobial Activity against Staphylococcus aureus and Methicillin-Resistant S. aureus Pathogens Isolated from the Sinonasal Niche of Chronic Rhinosinusitis Patients

Corynebacterium accolens is the predominant species of the healthy human nasal microbiota, and its relative abundance is decreased in the context of chronic rhinosinusitis (CRS). This study aimed to evaluate the antimicrobial potential of C. accolens isolated from a healthy human nasal cavity against planktonic and biofilm growth of Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA) clinical isolates (CIs) from CRS patients. Nasal swabs from twenty non-CRS control subjects were screened for the presence of C. accolens using microbiological and molecular techniques. C. accolens CIs and their culture supernatants were tested for their antimicrobial activity against eight S. aureus and eight MRSA 4CIs and S. aureus ATCC25923. The anti-biofilm potential of C. accolens cell-free culture supernatants (CFCSs) on S. aureus biofilms was also assessed. Of the 20 nasal swabs, 10 C. accolens CIs were identified and confirmed with rpoB gene sequencing. All isolates showed variable antimicrobial activity against eight out of 8 S. aureus and seven out of eight MRSA CIs. Culture supernatants from all C. accolens CIs exhibited a significant dose-dependent antibacterial activity (p < 0.05) against five out of five representative S. aureus and MRSA CIs. This inhibition was abolished after proteinase K treatment. C. accolens supernatants induced a significant reduction in metabolic activity and biofilm biomass of S. aureus and MRSA CIs compared to untreated growth control (p < 0.05). C. accolens exhibited antimicrobial activity against S. aureus and MRSA CIs in both planktonic and biofilm forms and holds promise for the development of innovative probiotic therapies to promote sinus health.

Microbiology, Histopathology, and Radiographic Findings in Silent Sinus Syndrome

BACKGROUND

The histopathology and microbiology associated with silent sinus syndrome (SSS) have not been well described.

OBJECTIVE

This study details the histopathological and microbiological characteristics in addition to radiographic findings of SSS in comparison to those of chronic maxillary sinusitis (CRS).

METHODS

42 patients diagnosed with SSS at Mayo Clinic Hospital in Arizona were identified. Paranasal computed tomography scans of the 42 SSS patients as well as 42 matched CRS patients were analyzed in order to assess differences in the prevalence of septal spurs/deviation. 20 of the SSS patients and 19 of the matched CRS patients also had histopathology and microbiology reports, which were compiled and summarized. Additionally, 19 SSS and 19 matched CRS patients were contacted via phone survey for a more complete patient history regarding maxillary dental disease/surgery.

RESULTS

SSS patients have a significantly higher prevalence of septal spurs/deviation than CRS patients. The microbiomes of SSS patients more closely resemble those of healthy controls than those of CRS patients. Analysis of the histopathology of SSS reveals chronic, non-specific inflammation similar to that seen in non-eosinophilic CRS without polyps. SSS patients were significantly more likely to have a history of maxillary dental disease requiring surgery.

CONCLUSION

These data support the hypothesis that the pathogenesis of SSS is more likely due to anatomical/mechanical factors than inflammatory/microbiological factors.

SARS-CoV-2 microbiome dysbiosis linked disorders and possible probiotics role

In December 2019, a pneumonia outbreak of unknown etiology was reported which caused panic in Wuhan city of central China, which was later identified as Coronavirus disease (COVID-19) caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by the Chinese Centre for Disease Control and Prevention (CDC) and WHO. To date, the SARS-CoV-2 spread has already become a global pandemic with a considerable death toll. The associated symptoms of the COVID-19 infection varied with increased inflammation as an everyday pathological basis. Among various other symptoms such as fever, cough, lethargy, gastrointestinal (GI) symptoms included diarrhea and IBD with colitis, have been reported. Currently, there is no sole cure for COVID-19, and researchers are actively engaged to search out appropriate treatment and develop a vaccine for its prevention. Antiviral for controlling viral load and corticosteroid therapy for reducing inflammation seems to be inadequate to control the fatality rate. Based on the available related literature, which documented GI symptoms with diarrhea, inflammatory bowel diseases (IBD) with colitis, and increased deaths in the intensive care unit (ICU), conclude that dysbiosis occurs during SARS-COV-2 infection as the gut-lung axis cannot be ignored. As probiotics play a therapeutic role for GI, IBD, colitis, and even in viral infection. So, we assume that the inclusion of studies to investigate gut microbiome and subsequent therapies such as probiotics might help decrease the inflammatory response of viral pathogenesis and respiratory symptoms by strengthening the host immune system, amelioration of gut microbiome, and improvement of gut barrier function.

Antibiotic Treatment for Chronic Rhinosinusitis: Prescription Patterns and Associations With Patient Outcome and the Sinus Microbiota

Background

Chronic rhinosinusitis (CRS) is a common and debilitating inflammatory condition of the sinuses, afflicting 5% of the general population. Although antibiotics are frequently prescribed for the medical management of CRS, there is surprisingly little evidence to support their efficacy. In this study, we aimed to establish associations between medication usage, the sinus microbiota and patients’ clinical outcomes.

Methods

Antibiotic prescription patterns for the year before sample collection of 156 CRS patients, 45 disease control patients (mostly requiring septoplasty and inferior turbinate reduction) and 35 healthy control subjects were examined and analyzed together with previously published bacterial 16S rRNA gene amplicon data from our group.

Results

The highest antibiotic usage was observed among the two CRS patient categories. Despite heavy antibiotic usage, CRS patients’ clinical outcomes as indicated by patient questionnaires and radiologic scores were similar to those patients that did not receive any antibiotics. The sinus microbiota was dominated by members of the bacterial genera Corynebacterium and Staphylococcus in all three cohorts. Bacterial community dispersion as measured by principal coordinate analysis was significantly higher in CRS patients compared to healthy control subjects, but not disease control patients. Pairwise comparisons within cohorts revealed differences in the relative 16S rRNA gene sequence abundances of the genera Staphylococcus and Lawsonella between antibiotic users and non-users. However, overall antibiotic effects were minimal and unpredictable.

Conclusion

The unpredictable effects of antibiotic treatment on the sinus microbiota found in this study, together with the lack of differences in patients’ symptom scores between cohorts, do not support preoperative antibiotic treatment for CRS patients.

Cystic fibrosis microbiome: analysis of nasal middle meatus and sputum in different lung disease stages

BACKGROUND: Culture independent methods of molecular detection of microbiome have shown the polymicrobial nature of respiratory infections in cystic fibrosis, with pathogenic agents undetectable in conventional culture methods. Composition and diversity of the airway microbiome are still poorly understood. METHODOLOGY: This study evaluated the airway microbiome in 31 adult cystic fibrosis patients via the analysis of 16S rRNA se- quences by next generation sequencing. RESULTS: Staphylococcus, Streptococcus and Corynebacterium were the most abundant genera in the middle meatus, and Pseudo- monas, Haemophilus and Prevotella were the most abundant in sputum. In patients with advanced disease (FEV1< 50%), there was an increase in the prevalence of Pseudomonas in both sample types when studied separately. In each patient, in a paired analysis, the sputum and middle meatus showed similar microbiome composition in mild or moderate disease (FEV1≥ 50%). In patients with severe lung disease, the relative abundance of Pseudomonas had a positive correlation in both collection sites. CONCLUSIONS: This is the first Brazilian study to evaluate the airway microbiome in cystic fibrosis patients. Our findings agree with those in the international literature and indicate the role of Pseudomonas in the sputum and middle meatus in patients with advanced disease.

Multiomic analysis identifies natural intrapatient temporal variability and changes in response to systemic corticosteroid therapy in chronic rhinosinusitis

INTRODUCTION

The pathophysiology and temporal dynamics of affected tissues in chronic rhinosinusitis (CRS) remain poorly understood. Here, we present a multiomics-based time-series assessment of nasal polyp biopsies from three patients with CRS, assessing natural variability over time and local response to systemic corticosteroid therapy.

METHODS

Polyp tissue biopsies were collected at three time points over two consecutive weeks. Patients were prescribed prednisone (30 mg daily) for 1 week between Collections 2 and 3. Polyp transcriptome, proteome, and microbiota were assessed via RNAseq, SWATH mass spectrometry, and 16S ribosomal RNA and ITS2 amplicon sequencing. Baseline interpatient variability, natural intrapatient variability over time, and local response to systemic corticosteroids, were investigated.

RESULTS

Overall, the highly abundant transcripts and proteins were associated with pathways involved in inflammation, FAS, cadherin, integrin, Wnt, apoptosis, and cytoskeletal signaling, as well as coagulation and B- and T-cell activation. Transcripts and proteins that naturally varied over time included those involved with inflammation- and epithelial-mesenchymal transition-related pathways, and a number of common candidate target biomarkers of CRS. Ten transcripts responded significantly to corticosteroid therapy, including downregulation of TNF, CCL20, and GSDMA, and upregulation of OVGP1, and PCDHGB1. Members of the bacterial genus Streptococcus positively correlated with immunoglobulin proteins IGKC and IGHG1.

CONCLUSIONS

Understanding natural dynamics of CRS-associated tissues is essential to provide baseline context for all studies on putative biomarkers, mechanisms, and subtypes of CRS. These data further our understanding of the natural dynamics within nasal polypoid tissue, as well as local changes in response to systemic corticosteroid therapy.