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.

Enhanced phylogenetic insights into the microbiome of chronic rhinosinusitis through the novel application of long read 16S rRNA gene amplicon sequencing.

INTRODUCTION: 16S rRNA next generation sequencing (NGS) has been the de facto standard of microbiome profiling. A limitation of this technology is the inability to accurately assign taxonomy to a species order. Long read 16S sequencing platforms, including Oxford Nanopore Technologies (ONT), have the potential to overcome this limitation. The paranasal sinuses are an ideal niche to apply this technology, being a low biomass environment where bacteria are implicated in disease propagation. Characterising the microbiome to a species order may offer new pathophysiological insights. METHODOLOGY: Cohort series comparing ONT and NGS biological conclusions. Swabs obtained endoscopically from the middle meatus of 61 CRSwNP patients underwent DNA extraction, amplification and dual sequencing (Illumina Miseq (NGS) and ONT GridION). Agreement, relative abundance, prevalence, and culture correlations were compared. RESULTS: Mean microbiome agreement between sequencers was 61.4%. Mean abundance correlations were strongest at a familial/genus order and declined at a species order where NGS lacked resolution. The most significant discrepancies applied to Corynebacterium and Cutibacterium, which were estimated in lower abundance by ONT. ONT accurately identified 84.2% of cultured species, which was significantly higher than NGS. CONCLUSIONS: ONT demonstrated superior resolution and culture correlations to NGS, but underestimated core sinonasal taxa. Future application and optimisation of this technology can advance our understanding of the sinonasal microenvironment.

Differential proteomic expression in non-functional pituitary neuroendocrine tumours and pituitary glands.

INTRODUCTION: Pituitary neuroendocrine tumours (PitNETs) are common accounting for 10 to 25 % of all intracranial tumours. This project describes the feasibility of developing a novel membrane-based biomarker that could be used for fluorescent guided surgery. The aim was to catalogue the differential expression of membrane proteins between non-functional PitNETs and pituitary glands. METHODOLOGY: Ten pituitary gland tissue specimens were obtained from the National Institute of Health (NIH) NeuroBio-Bank and twenty non-functional PitNETs were obtained from the Northwestern University Nervous System Tumour Bank. Mass spectrometry analysis using an Orbitrap Fusion Lumos Tribrid Mass Spectrometer linked to a Dionex Ultimate 3000 UPLC system was undertaken. Data Dependent Acquisition Mass Spectrometry and Data Independent Acquisition Mass Spectrometry was then completed. Pathway enrichment analysis was performed using clusterProfiler v4.6.0. Functional enrichment analysis was conducted using Gene Ontology terms and Reactome pathways. RESULTS: Differential expression analysis between the two groups revealed a total of 2110 significant differently expressed proteins (DEPs), with 1387 of these also having a Log2 fold change either greater than 1, or less than -1. Of the 2110 DEPs, 925 were upregulated in tumours compared to control, while 1185 were downregulated. CONCLUSION: We have demonstrated a proteomic comparison between non-functional PitNETs and normal pituitary glands. These results demonstrate differences consistent with contemporary literature but shows that NOTCH3 and PTPRJ are up-regulated in non-functional PitNETs compared to pituitary glands.

Low pH nasal rinse solution enhances mupirocin antimicrobial efficacy.

BACKGROUND: Chronic rhinosinusitis (CRS) is a common condition negatively impacting a patient's quality of life. It has been hypothesized that bacterial biofilms are involved in the pathogenesis of CRS due to their persistence and difficulty to eradicate with conventional antibiotic therapy. Hence, the topical delivery of antibiotics via nasal rinse solution has gained a lot of attention due to the ability to deliver higher local concentrations, with less systemic absorption and side effects. This study investigates the efficacy of mupirocin dissolved in the 3 most commonly used sinus rinses in Australia Neilmed (isotonic saline), Flo Sinus Care (sodium chloride, sodium bicarbonate, potassium chloride, glucose anhydrous and calcium lactate and Pentahydrate) and FloCRS (sodium chloride, potassium chloride and xylitol). METHODS: Planktonic and biofilm cultures of S. aureus (ATCC25923, 2 methicillin-resistant S. aureus (MRSA) (C222 and C263), and 2 methicillin-susceptible S. aureus (MSSS) (C311 and C349) clinical isolates) were treated with mupirocin dissolved in three sinus rinses (Neilmed, Flo Sinus Care and FloCRS with different pH). To establish whether pH was a significant factor in determining antibiotic activity, experiments with Flo CRS were performed both at pH 5.64 and elevated pH 7.7. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for planktonic cells. The biofilm biomass and metabolic activity were assessed by using crystal violet assay and alamarBlue assay respectively. RESULTS: The combination of mupirocin in low pH (pH 5.64) sinus rinse (FloCRS) had the highest efficacy in reducing the growth of S. aureus in both the planktonic and biofilm forms. Mupirocin diluted in FloCRS (pH 5.64) showed a significantly higher reduction in both biomass and metabolic activity than that was observed when mupirocin was diluted in Neilmed, Flo Sinus Care or FloCRS (pH 7.7). CONCLUSION: The choice of irrigant solution for topical mupirocin delivery appears to be important for antimicrobial activity. The delivery of mupirocin via low pH FloCRS could be useful in eliminating S. aureus biofilms present on the sinus mucosa of patients with CRS.

Low pH nasal rinse solution enhances mupirocin antimicrobial efficacy.

BACKGROUND: Chronic rhinosinusitis (CRS) is a common condition negatively impacting a patient's quality of life. It has been hypothesized that bacterial biofilms are involved in the pathogenesis of CRS due to their persistence and difficulty to eradicate with conventional antibiotic therapy. Hence, the topical delivery of antibiotics via nasal rinse solution has gained a lot of attention due to the ability to deliver higher local concentrations, with less systemic absorption and side effects. This study investigates the efficacy of mupirocin dissolved in the 3 most commonly used sinus rinses in Australia Neilmed (isotonic saline), Flo Sinus Care (sodium chloride, sodium bicarbonate, potassium chloride, glucose anhydrous and calcium lactate and Pentahydrate) and FloCRS (sodium chloride, potassium chloride and xylitol). METHODS: Planktonic and biofilm cultures of S. aureus (ATCC25923, 2 methicillin-resistant S. aureus (MRSA) (C222 and C263), and 2 methicillin-susceptible S. aureus (MSSS) (C311 and C349) clinical isolates) were treated with mupirocin dissolved in three sinus rinses (Neilmed, Flo Sinus Care and FloCRS with different pH). To establish whether pH was a significant factor in determining antibiotic activity, experiments with Flo CRS were performed both at pH 5.64 and elevated pH 7.7. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for planktonic cells. The biofilm biomass and metabolic activity were assessed by using crystal violet assay and alamarBlue assay respectively. RESULTS: The combination of mupirocin in low pH (pH 5.64) sinus rinse (FloCRS) had the highest efficacy in reducing the growth of S. aureus in both the planktonic and biofilm forms. Mupirocin diluted in FloCRS (pH 5.64) showed a significantly higher reduction in both biomass and metabolic activity than that was observed when mupirocin was diluted in Neilmed, Flo Sinus Care or FloCRS (pH 7.7). CONCLUSION: The choice of irrigant solution for topical mupirocin delivery appears to be important for antimicrobial activity. The delivery of mupirocin via low pH FloCRS could be useful in eliminating S. aureus biofilms present on the sinus mucosa of patients with CRS.

The clinical outcomes of medical therapies in chronic rhinosinusitis are independent of microbiomic outcomes: a double-blinded, randomised placebo-controlled trial.

BACKGROUND: Oral and topical corticosteroids, and antibiotics form the mainstay medical treatment of chronic rhinosinusitis (CRS). Clinical outcomes vary depending on the chosen therapy, resident microbiome and disease phenotype. We conducted a double- blinded, placebo-controlled Randomised Controlled Trial (RCT) to investigate effects of medical therapy on clinical outcomes and associated microbiome shifts. METHODOLOGY: Fifty eligible patients (CRS with and without polyps) were treated for 3 weeks after randomisation into 3 arms: na- mely oral prednisolone, topical budesonide irrigations and oral doxycycline; each with appropriate placebo. Clinical scoring and microbiome swabs were performed on enrolment, at treatment completion and 3-weeks post treatment completion. Microbiome analysis was performed using the llumina-MiSeq next generation sequencing platform and QIME-2 pipeline. RESULTS: Significant improvement in clinical scores was observed in prednisolone and budesonide arms at treatment completion but not with antibiotic. Sub-group analysis showed more pronounced effects in patients with polyposis. Corynebacterium and Staphylococcus species predominated, with variable bacterial relative abundance among different treatments at all time-points. The only significant microbiome finding was an increase in bacterial diversity in topical budesonide group immediately after treatment, which returned to baseline 3-weeks post treatment. CONCLUSION: Clinical improvement was significant with oral and topical steroid but not empirical antibiotic. Although there were some associated microbiome changes with the various treatments, we could not ascertain the consistency of these and whether they do have a clinical significance at all.

The global transcriptomic signature in sinonasal tissues reveals roles for tissue type and chronic rhinosinusitis disease phenotype.

BACKGROUND: RNA sequencing (RNA-Seq) allows the characterization of a global transcriptomic signature in a least-biased fashion, but few studies have applied this method to investigate the pathophysiology of CRS. METHODS: We collected mucosal tissue samples from 6 CRS without nasal polyps (CRSsNP), 6 CRS with nasal polyps (CRSwNP), and 6 control patients. Additional matched polyp samples were collected from the 6 CRSwNP patients. RNA was extracted and sequenced on the Illumina HiSeq-2500. Differential gene expression and pathway analyses were performed. RESULTS: CRSsNP showed evidence of upregulated interferon-mediated immunity, MHC-class-I mediated antigen presentation, CXCR3 binding, neutrophil chemotaxis and degranulation, and potential downregulation of genes related to cilia movement and production. CRSwNP polyp tissue showed upregulation of B-cell mediated immune responses, but reduced expression of genes related to epithelial morphogenesis and haemostasis. Polyps also showed a generalized reduction of positive gene regulation. The sinonasal transcriptomic signature was largely determined by tissue type (polyp versus mucosa) and disease phenotype, with minimal signal originating from the individual patient. CONCLUSION: RNA-Seq is a useful tool to explore the complex pathophysiology of CRS. Our findings stress the importance of tissue selection in molecular research utilizing sinonasal tissue, and demonstrate the limitation of the sNP/wNP paradigm (and the importance of endotyping). On the other hand, classical CRSsNP/wNP disease phenotypes played some role in determining the global transcriptomic signature, and should not be hastily discarded. The value of RNA-Seq-described transcriptomic signatures in exploring endotypes is yet to be explored in future studies.

Scoping review of chronic rhinosinusitis proteomics.

BACKGROUND: Progressive advances in proteomic technology has improved our understanding of the chronic rhinosinusitis (CRS) pathogenesis and endotypes. This scoping review aims to present a comprehensive and descriptive analysis of nasal mucosa and mucus proteome of CRS patients. METHODOLOGY: Studies investigating the proteome of nasal mucosa and mucus from healthy and CRS patients via mass spectrometry were included. Critical appraisal of methodological quality was conducted with extraction of protein lists. Gene set enrichment analysis (GSEA) was performed on studies including CRS patients. RESULTS: 2962 proteins were identified in the 21 studies included in this review. Eleven studies investigated the nasal mucus proteome and ten studies investigated the nasal mucosa proteome. Studies demonstrated heterogeneity in patients, sampling and mass spectrometry methodology. Samples from CRS patients suggested a trend in enrichment of immune system and programmed cell death pathways. Increased expression of proteins involved in cellular components including the cytoskeleton and adherens junctions was also present in CRS. CONCLUSIONS: Alterations in the healthy sinonasal proteome may lead to the increased immunological, metabolic and tissue remodeling processes observed in CRS. However, it is difficult to draw significant conclusions from the GSEA due to the heterogeneity present in the limited literature available. These findings allow us to direct further research to better understand CRS pathogenesis and its endotypes.

Zinc-depletion associates with tissue eosinophilia and collagen depletion in chronic rhinosinusitis.

BACKGROUND: Zinc plays an important role in many biological processes. Reduced zinc levels have been found in chronic rhinosinusitis (CRS) patients, however, its role in the pathophysiology of this disease remains unknown. This study examined zinc levels in the serum, mucus and tissue from CRS patients in relation to collagen content and eosinophil infiltration. The effect of zinc depletion on inflammatory cytokine production and collagen synthesis was assessed in vitro. METHODOLOGY: Zinc levels were determined in serum, mucus and tissue from controls, CRS with (CRSwNP) and without nasal polyps (CRSsNP) patients. Tissue zinc levels, collagen and inflammatory cell infiltration was examined using zinquin assays, immunofluorescence and histology on Tissue Micro Arrays. Cytokine expression and collagen synthesis was evaluated in zinc depleted primary human nasal epithelial cells (HNECs) and primary fibroblasts. RESULTS: CRSwNP patients showed reduced tissue zinc levels in correlation with a reduction in collagen content, and increased eosinophil numbers. Zinc depletion of HNECs and fibroblasts induced the production of pro-inflammatory cytokines and MUC5AC and reduced collagen secretion. CONCLUSIONS: These results suggest mucosal zinc depletion associates with tissue eosinophilia and collagen depletion in CRSwNP and induces pro-inflammatory cytokine expression and reduction of collagen synthesis in vitro.

The effect of topical treatments for CRS on the sinonasal epithelial barrier.

BACKGROUND: Several topical treatments are used in the management of Chronic Rhinosinusitis (CRS), some of which the safety and efficacy has yet to be determined. The purpose of this study was to investigate the effect of commonly used topical treatments on the sinonasal epithelial barrier. METHODS: Normal saline (0.9% Sodium Chloride), hypertonic saline (3% Sodium Chloride), FESS Sinu-Cleanse Hypertonic, FLO Sinus Care and Budesonide 1 mg/ 2 ml were applied to the apical side of air-liquid interface (ALI) cultures of primary human nasal epithelial cells (HNECs) from CRS patients (n=3) and non-CRS controls (n=3) for 24 hours. Epithelial barrier structure and function was assessed using trans-epithelial electrical resistance (TEER), measuring the passage of Fluorescein Isothiocyanate labelled Dextrans (FITC-Dextrans) and assessing the expression of the tight junction protein Zona Occludens-1 (ZO-1) using immunofluorescence. Toxicity was assessed using a Lactate Dehydrogenase (LDH) assay. Data was analysed using ANOVA, followed by Tukey HSD post hoc test. RESULTS: Hypertonic solution and budesonide significantly increased TEER values in CRS derived HNECs. In contrast, FESS Sinu-Cleanse Hypertonic significantly reduced TEER 5 minutes after application of the solution followed by an increase in paracellular permeability of FITC-Dextrans (30 minutes) and increased LDH levels 6 hours after application of the solution. CONCLUSIONS: Our findings confirm that isotonic and hypertonic saline solutions do not compromise epithelial barrier function in vitro but underscore the importance of examining safety and efficacy of over-the-counter wash solutions.

The persistence of intracellular Staphylococcus aureus in the sinuses: a longitudinal study.

BACKGROUND: Staphylococcus aureus (S. aureus) can reside within the sinonasal mucosa in chronic rhinosinusitis patients and causes recurrent infections. Within the host cell, S. aureus can evade host immune detection enabling its own survival. We hypothesise that S. aureus can persist within the sinonasal epithelium for a prolonged period without immune activation. METHODOLOGY: Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) undergoing two sinus surgeries were included. Immunohistochemistry and Haematoxylin and Eosin stains were used to determine intracellular S. aureus (ICSA) status and inflammatory cell count, respectively. One-way ANOVA and paired t-tests were performed for comparison between ICSA subgroups and within each subgroup, respectively. RESULTS: Histopathological specimens from 34 patients (68 procedures) were included. ICSA positivity (ICSA+) was seen in 43 specimens (63.2%) from 26 (76%) patients. 18 (52.9%) of those were ICSA+ in both operations while 8 (23.5%) patients were ICSA+ in only one of the operations. 8 (23.5%) patients were ICSA negative in both operations. There was no difference in the number of eosinophils, lymphocyte and neutrophils between ICSA subgroups. CONCLUSIONS: This study demonstrated that S. aureus is found intracellularly within CRSwNP tissue at multiple time points without an increase in the number of eosinophils, lymphocytes and neutrophils. This finding supports our hypothesis that ICSA is able to escape from host detection and resides within the sinonasal mucosa despite intense treatment.

Association between group 2 innate lymphoid cells enrichment, nasal polyps and allergy in chronic rhinosinusitis.

BACKGROUND: Group 2 innate lymphoid cells (ILC2s) were shown to be involved in the initiation and coordination of Th2-type immune responses in allergic disease animal models. Recently, ILC2s enrichment was noted in chronic rhinosinusitis (CRS) patients; however, the role of ILC2s in coordinating the Th2 response in CRS remains to be elucidated. Here, we characterize the ILC2 compartment in CRS by investigating the correlations between ILC2s, Th2 cells and Th2 cytokines expression in CRS patients. METHODS: We used flow cytometric analysis of sinonasal mucosal tissues of 29 CRS patients and 5 controls to quantify ILC2s and Th2 cells. Messenger RNA expression levels of IL-5, IL-13, IL-25, IL-33, TSLP and GATA3 were determined using qRT-PCR. RESULTS: ILC2s were significantly enriched in nasal polyps (CRSwNP) patients. Multivariate linear regression showed a significant positive association of ILC2 numbers with CRSwNP and allergic CRS and a negative association with the number of previous endoscopic sinus surgeries. Group 2 innate lymphoid cell numbers significantly correlated with Th2 cell frequencies. Messenger RNA expression levels of IL-5 and IL-13 were increased in CRSwNP compared with controls, while mRNA levels of IL-25 and GATA3 were significantly reduced. CONCLUSIONS: Our results characterize the complex interactions between ILC2s and other Th2 response elements in the context of CRS and suggest that ILC2 enrichment occurs in CRSwNP and in allergic CRS patients.

Small-colony variants and phenotype switching of intracellular Staphylococcus aureus in chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) has been linked to the gram-positive bacteria Staphylococcus aureus (S. aureus) in its biofilm or intracellular forms. Recent evidence suggests that S. aureus also exists in a small-colony variant (SCV) form as a mechanism of altering its virulence capabilities. The aim of this study was to investigate the presence of SCVs in sinonasal mucosa of CRS patients and whether the phenomenon of phenotype switching can be applied to intracellular epithelial infections. METHODS: Sinonasal specimens were examined for the presence of intramucosal S. aureus and characterized to the strain level. An airway epithelial cell culture infection model was utilized to investigate whether bacteria were capable of alterations in virulence phenotype. RESULTS: Intramucosal organisms harvested from sinonasal biopsies demonstrate phenotypic growth patterns and lack of coagulase activity consistent with SCVs. Intracellular infection of airway epithelial cell cultures with S. aureus led to decreased secretion of enterotoxins and phenotypic growth alterations consistent with SCVs. CONCLUSIONS: Regulation of S. aureus virulence factors is a dynamic process, and exposure to the intracellular environment appears to provide the necessary conditions to enable these alterations in an attempt for the bacterium to survive and persist within host tissues. Further work is required to ascertain whether SCVs in CRS hold a clinically relevant pathogenic role in recalcitrant disease.

Deferiprone and Gallium-Protoporphyrin Chitogel as an antimicrobial treatment: Preclinical studies demonstrating antimicrobial activity for S. aureus infected cutaneous wounds.

Staphylococcus aureus (S. aureus) is one of the most common wound pathogens with increased resistance towards currently available antimicrobials. S. aureus biofilms lead to increase wound chronicity and delayed healing. Chitosan-dextran hydrogel (Chitogel) loaded with the hydroxypyridinone-derived iron chelator Deferiprone (Def) and the heme analogue Gallium-Protoporphyrin (GaPP) have previously been shown to have antimicrobial effects in clinical sinusitis. In this study, the efficacy of Chitogel loaded with Def, GaPP and a combination of Def and GaPP, were investigated in an S. aureus biofilm infected wound murine model over 10 days of treatment. Bacterial wound burden was monitored daily showing a significant decrease in bacterial bioburden on days 6 and 8 when treated with Def-GaPP Chitogel (log10 1.0 and 1.2 reduction vs control, respectively). The current study demonstrates that the combination of Def-GaPP delivered in a Chitogel in vivo is not only effective in reducing S. aureus biofilm infection, but also improves cutaneous healing via effects on reduced inflammation, promotion of anti-inflammatory macrophage phenotype and marked early collagen deposition in the wound bed. This delivery platform presents a promising alternative non-toxic, antibacterial, wound-promoting treatment as a novel approach for the management of S. aureus wound infections that warrants further clinical investigation.

Inflammasome gene expression alterations in Staphylococcus aureus biofilm-associated chronic rhinosinusitis.

BACKGROUND: The role of inflammasomes in chronic inflammation has been the subject of intense research in recent years. Chronic rhinosinusitis (CRS), a persistent inflammatory disease, continues to be investigated hoping that a clearer pathophysiologic description will guide discovery of future treatment modalities. This study investigates the role of inflammasome complexes in CRS patients with Staphylococcus aureus biofilm infection, a key culprit associated with disease severity and recalcitrance. METHODOLOGY: Sinonasal tissue samples were collected from CRS patients with (P+) and without (P-) polyps and controls. S. aureus biofilm status was obtained using fluorescence in situ hybridization and classified as biofilm positive (B+) or negative (B-). RNA was analysed using a Human Inflammasome PCR array, profiling the expression of 84 genes involved in inflammasome function. RESULTS: Sixteen samples were obtained: 5 B+P+, 5 B-P- and 6 controls. Comparing B+P+ vs. controls showed the greatest number of differentially expressed genes. In particular, Absent in Melanoma 2 (AIM2) was consistently and significantly up-regulated in the B+P+ vs. B-P- and controls. In contrast, when comparing the B-P- vs. controls, no genes showed significant changes. CONCLUSION: Our results indicate the involvement of inflammasome complexes and their signalling pathways in CRS patients with polyps and S. aureus biofilms. In particular, AIM2, activated by intracellular double-stranded DNA, is up-regulated in this group, implying that S. aureus may play a role in intracellular triggering of the inflammasome response. Studies with further patient stratification and assessing corresponding protein expression are needed to further characterize the role of inflammasomes in CRS.

Clinical characterization of genetic hearing loss caused by a mutation in the POU4F3 transcription factor.

OBJECTIVES: To describe the detailed auditory phenotype of DFNA15, genetic hearing loss associated with a mutation in the POU4F3 transcription factor, and to define genotype-phenotype correlations, namely, how specific mutations lead to particular clinical consequences. DESIGN: An analysis of clinical features of hearing-impaired members of an Israeli family, family H, with autosomal dominant-inherited hearing loss. SETTING: Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Audiology, Rabin Medical Center, Petah Tiqwa, Israel; and audiological centers. PARTICIPANTS: Clinical features of 11 affected and 5 unaffected individuals older than 40 years from family H were studied. Mutation analysis was performed in 6 presymptomatic individuals younger than 30 years; clinical features were analyzed in 4 of these family H members. INTERVENTIONS: Hearing was measured by pure-tone audiometry and speech audiometry on all participating relatives of family H. Immittance testing (tympanometry and acoustic reflexes), auditory brainstem response, and otoacoustic emissions were done in a selected patient population. RESULTS: The patients presented with progressive high-tone sensorineural hearing impairment, which became apparent between ages 18 and 30 years. The hearing impairment became more severe with time, eventually causing significant hearing loss across the spectrum at all frequencies. CONCLUSIONS: Our results indicate that POU4F3 mutation-associated deafness cannot be identified through clinical evaluation, but only through molecular analysis. Intrafamilial variability suggests that other genetic or environmental factors may modify the age at onset and rate of progression.

Nutritional aspects of dysphagia.

Adequate nutritional support is essential in the management of the dysphagic patient. In this article we discuss the indications, advantages and limitations of different types of oral and artificial feeding schedules.

Metastasis of a renal cell carcinoma to the nose and paranasal sinuses.

We present a case of a metastasis of a renal cell carcinoma to the nose and paranasal sinuses. A 66 year old male patient developed a mass in his left nasal cavity and paranasal sinuses, five years after he underwent a left sided nefrectomy for a renal cell carcinoma. The histopathologic examination of the nasal mass showed metastasis of a renal cell carcinoma. A craniofacial resection was performed followed by radiotherapy.

Calcific tendinitis of the longus colli muscle.

BACKGROUND: To the best of our knowledge, only one patient with calcium hydroxyapatite deposition disease (CHADD) of the longus colli muscle has been reported in the otolaryngology literature. METHODS: Clinical findings and results of imaging studies in such a patient are reported. RESULTS: Two particular imaging findings of this disorder are discussed. First, disappearance of calcifications over the short time frame of a week, accompanied by the resolution of clinical symptoms. Second, the presence of an extensive region of high signal intensity extending from the skull base to the lower border of C5, on T2-weighted spin-echo magnetic resonance (MR) images. CONCLUSIONS: Knowledge of the characteristic clinical spectrum and imaging features of this disorder are crucial for a correct diagnosis of this uncommon cause of odynophagia and dysphagia.