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1.
Microbes Infect ; 26(4): 105317, 2024.
Article in English | MEDLINE | ID: mdl-38452852

ABSTRACT

The discovery of bacterial microcolonies in tonsillar tissue of patients with tonsillar hyperplasia has raised the question of their role in provoking the local immune response. Tonsils collected from patients undergoing tonsillectomy were stained for three clinically relevant bacterial taxa and lymphocytes. The bacterial composition and abundance of microcolonies was investigated using a combination of laser-microdissection, amplicon sequencing and Droplet Digital polymerase chain reaction. Microcolonies were detected in most samples (32/35) with a high prevalence of Haemophilus influenzae (78% of samples). B and T cell lymphocytes were significantly higher in the epithelium adjacent to microcolonies compared to epithelium distal to microcolonies. Furthermore, significant positive and negative correlations were identified between bacterial taxa and lymphocytes. Genus Streptococcus, which includes Group A Streptococcus (traditionally described as the main pathogen of tonsillar hyperplasia), was found in low abundance in this study. These results suggest other potential pathogens may be involved in stimulating the local immune response leading to tonsillar hyperplasia.


Subject(s)
Bacteria , Hyperplasia , Palatine Tonsil , Humans , Palatine Tonsil/microbiology , Palatine Tonsil/pathology , Hyperplasia/microbiology , Hyperplasia/pathology , Child , Female , Male , Bacteria/classification , Bacteria/isolation & purification , Bacteria/genetics , Child, Preschool , Adolescent , Tonsillectomy , Tonsillitis/microbiology , Tonsillitis/pathology , Tonsillitis/immunology , Adult , Young Adult
2.
Microbiol Spectr ; 12(2): e0170923, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38168683

ABSTRACT

Polymyxin B and ethylenediaminetetraacetic acid are antimicrobials possessing antibiofilm activity. They act by displacement and chelation, respectively, of divalent cations in bacterial membranes and may therefore act synergistically when applied in combination. If so, this combination of agents may be useful for the treatment of diseases like cystic fibrosis (CF), in which biofilms are present on the respiratory epithelium. We used checkerboard assays to investigate the synergy between these agents using reference strains Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 6538 in planktonic form. We then determined the efficacy of each agent against biofilms of both species grown on 96-pin lids and proceeded to combination testing against the P. aeruginosa reference strain and 10 clinical isolates from patients with CF. Synergism was observed for planktonic forms of both species and for biofilms of P. aeruginosa. The susceptibility of biofilms of P. aeruginosa clinical isolates to these agents was variable compared to the laboratory reference strain. This combination of agents may be useful in the management of biofilm-associated conditions, particularly those amenable to topical therapies. These results provide a basis upon which the antimicrobial and antibiofilm efficacy of preparations containing these agents may be enhanced.IMPORTANCEBacteria living in biofilms produce a protective matrix which makes them difficult to kill. Patients with severe respiratory disease often have biofilms. Polymyxin B is an antibiotic commonly used in topical medications, such as eye drops and nasal sprays. Ethylenediaminetetraacetic acid (EDTA) is used widely as a preservative in medication but also has antimicrobial properties. It has been hypothesized that Polymyxin B and EDTA could have a synergistic relationship: when used in combination their antimicrobial effect is enhanced. Here, we evaluated the levels at which Polymyxin B and EDTA work together to kill common pathogens Pseudomonas aeruginosa and Staphylococcus aureus. We found that Polymyxin B and EDTA were synergistic. This synergy may be useful in the management of planktonic infection with P. aeruginosa and S. aureus, or biofilm infection with P. aeruginosa. This synergy may be beneficial in the treatment of respiratory biofilms, in which P. aeruginosa biofilms are common.


Subject(s)
Anti-Infective Agents , Cystic Fibrosis , Pseudomonas Infections , Staphylococcal Infections , Humans , Polymyxin B/therapeutic use , Edetic Acid , Pseudomonas aeruginosa , Staphylococcus aureus , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/therapeutic use , Biofilms , Cystic Fibrosis/microbiology , Microbial Sensitivity Tests
3.
Ann Otol Rhinol Laryngol ; 133(3): 355-362, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38044532

ABSTRACT

Surgeons have a high rate of work-related musculoskeletal injuries; an area that has received little attention. These injuries result in surgeons performing less efficiently, needing to take time off work, suffering higher rates of burnout, and may ultimately lead surgeons to retire earlier than planned. Otorhinolaryngologists are at particular risk for work-related musculoskeletal injuries. Beyond the clinician, sustaining such injuries can negatively impact patient safety. Ergonomic interventions have been used effectively to reduce work-related musculoskeletal injuries in other professions, yet not in surgery. With traditional teachings of ideal body postures to avoid injury and manual handling training being re-evaluated, it is important to explore evidence based interventions for reducing work-related musculoskeletal injuries in otorhinolaryngologists. New research encourages us to shift the focus away from the traditional one-size-fits-all approach to ergonomics and toward postural recommendations and education that promote a dynamic, individualized approach to avoiding sustained, static and awkward postures.


Subject(s)
Musculoskeletal Diseases , Occupational Diseases , Surgeons , Humans , Posture , Musculoskeletal Diseases/prevention & control , Ergonomics , Operating Rooms , Occupational Diseases/etiology , Occupational Diseases/prevention & control
4.
Expert Rev Clin Immunol ; 19(8): 911-920, 2023.
Article in English | MEDLINE | ID: mdl-37378564

ABSTRACT

INTRODUCTION: Chronic rhinosinusitis (CRS) is characterized by inflammation of the paranasal sinus mucosa persisting for more than 12 weeks. This condition is associated with reduced quality-of-life and causes a high direct and indirect economic burden. Several pathogenic factors have been attributed to CRS, including bacterial and fungal biofilms on the sinonasal mucosa. Biofilms are well-established contributors to recalcitrance to treatment in other chronic inflammatory mucosal conditions such as cystic fibrosis and otitis media. AREAS COVERED: This review will present an overview of the role of biofilms in CRS, including the evidence for biofilms being present on the sinonasal mucosa and their implications for disease severity. Furthermore, the interactions between biofilms and host-mediated immune factors are explored. EXPERT OPINION: The eradication of biofilms has been a focus of research shortly after their recognition as a cause of disease. The currently available methodologies for identifying biofilms on mucosal surfaces are not sufficiently well-developed to be used in a clinical setting. A more accurate, cheaper, faster approach for biofilm detection is necessary, and molecular techniques may provide the possibility for this.


Subject(s)
Rhinitis , Sinusitis , Humans , Nasal Mucosa/microbiology , Biofilms , Chronic Disease
5.
Cancer Epidemiol ; 85: 102393, 2023 08.
Article in English | MEDLINE | ID: mdl-37267678

ABSTRACT

BACKGROUND: An increasing trend of oropharyngeal cancer (OPC) has been reported in several countries with different demographic characteristics, and often attributed to increases in human papillomavirus (HPV) infection. The survival of patients with OPC has steadily improved, especially for those with positive HPV status. This study assessed the incidence, trends, and survival of OPC in Aotearoa New Zealand (NZ) by age at diagnosis, sex and ethnicity. METHODS: The study included all 2109 patients resident in NZ with a primary diagnosis of oropharyngeal squamous cell carcinoma from 2006 to 2020, identified from the National Cancer Registry. We assessed age-standardised incidence rate (ASR), annual percent change (APC) and overall and relative survival rates. RESULTS: The average annual incidence of OPC was 2.2 per 100,000 population. There was a steady increase of 4.9% per year over 15 years. Although the incidence rates were higher in males over the study period, the overall rate of increase was similar in males (4.9%) and in females (4.3%). The incidence was highest in the 50-69-year group (8.8/100,000 population). This age group had an incidence that increased by 7.5% per year to 2018, and then declined. The main increase in rates was seen between the birth cohort of 1946-50 and that of 1956-60. The increase in incidence was seen in Maori and Pakeha/European populations, but no increase was seen in Pacific or Asian populations. The 5-year overall relative survival rate improved from 69% in 2006-13 to 78% in 2014-20. Survival rates were lower in older patients, females, and Maori patients. CONCLUSION: This study confirmed a substantial increase in OPC incidence in NZ, with some evidence to suggest a recent slowing in this increase. Maori and Pakeha/European had the highest incidence, while Pacific and Asian populations showed the lowest rates and no increase over the study period. Survival rates have improved over time, but remained lower in some demographic groups.


Subject(s)
Head and Neck Neoplasms , Oropharyngeal Neoplasms , Papillomavirus Infections , Squamous Cell Carcinoma of Head and Neck , Aged , Female , Humans , Male , Head and Neck Neoplasms/epidemiology , Incidence , New Zealand/epidemiology , Oropharyngeal Neoplasms/epidemiology , Papillomavirus Infections/epidemiology , Squamous Cell Carcinoma of Head and Neck/epidemiology , Middle Aged
7.
Int Forum Allergy Rhinol ; 13(10): 1962-1965, 2023 10.
Article in English | MEDLINE | ID: mdl-36846913

ABSTRACT

KEY POINTS: Bacterial composition is uniform in the sinuses of postviral olfactory dysfunction patients. Significant reduction of genus Corynebacterium in PVOD patients compared to controls.


Subject(s)
Olfaction Disorders , Paranasal Sinuses , Humans , Smell , Nasal Cavity , Bacteria
8.
Laryngoscope ; 133(10): 2490-2495, 2023 10.
Article in English | MEDLINE | ID: mdl-36644968

ABSTRACT

OBJECTIVES: Bacterial biofilms on the sinonasal mucosa, especially biofilms of Staphylococcus aureus, are associated with greater severity and recalcitrance of chronic rhinosinusitis (CRS). There are few, if any, antibiofilm agents suitable for sinonasal application available for the management of this problem. Nasodine® Nasal Spray (Nasodine) is a 0.5% povidone-iodine-based formulation that has been developed for sinonasal application. We investigated the antibiofilm efficacy of Nasodine to determine whether it may be a candidate for the treatment of biofilm-associated CRS. METHODS: Biofilms of S. aureus ATCC 6538 were grown in vitro using the Centers for Disease Control biofilm reactor. Intact biofilms were treated by immersion in 0.9% saline (control), half concentration Nasodine, or full concentration Nasodine for between 5 min and 6 h. Further biofilm cells were dispersed into suspension then treated for between 30 s and 5 min. Surviving bacteria were then enumerated by culture and counting colonies, and the log10 reduction in viable bacteria was compared with control. RESULTS: Nasodine demonstrated time and concentration-dependent bacterial killing against intact biofilm. Statistically significant reductions in viable bacteria from intact biofilms were seen with exposures as brief as 5 min. Nasodine consistently eradicated dispersed biofilm within 1 min. CONCLUSION: Nasodine is highly active against biofilms of S. aureus ATCC 6538 in vitro. Biofilm killing is impeded by the presence of the intact biofilm structure. LAY SUMMARY: In chronic rhinosinusitis (CRS), bacterial communities called biofilms are associated with more severe inflammation. An iodine-based nasal spray called Nasodine almost completely eradicates bacterial biofilms after 6 h of exposure. Nasodine may be useful for treating CRS. Laryngoscope, 133:2490-2495, 2023.


Subject(s)
Rhinitis , Sinusitis , Humans , Staphylococcus aureus , Nasal Sprays , Sinusitis/complications , Biofilms , Povidone-Iodine/pharmacology , Chronic Disease , Rhinitis/complications
9.
ANZ J Surg ; 92(12): 3264-3267, 2022 12.
Article in English | MEDLINE | ID: mdl-36424855

ABSTRACT

BACKGROUND: Middle ear disease is common in children and, if untreated, can lead to long term complications. This study investigated whether ethnic or socioeconomic inequities existed among children referred to a tertiary regional paediatric ORL service. METHODS: All middle ear pathology related referrals to Starship Children's Hospital ORL service during 2018 and 2019 were reviewed. Online clinical records were accessed to collect demographic data and appointment outcomes. The relationships between ethnicity, socioeconomic status, age at referral and clinic attendance were analysed. RESULTS: A total of 1530 children were referred and 214 (14.0%) of these did not attend their scheduled appointments. Compared with the age of referral for European children, Maori children were referred on average 1.1 years older while Pasifika children were referred 2.4 years older. Compared to European children, Maori children were 4.3 times more likely to miss an appointment while Pasifika were 7.2 times more likely. Socioeconomic status had no significant effect on either age of referral or clinic attendance. CONCLUSIONS: Maori and Pasifika children with middle ear disease are referred later and are more likely to miss outpatient clinic appointments. Pasifika children are affected more than Maori.


Subject(s)
Ear Diseases , Otitis Media with Effusion , Child , Humans , Infant , Ethnicity , Ambulatory Care Facilities , Ear, Middle
10.
Microbiol Spectr ; 10(6): e0123922, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36318025

ABSTRACT

Despite antibiotics being the primary medical treatment for recurrent tonsillitis, the impact of antibiotics on the tonsillar microbiome is not well understood. This study aimed to determine the effect of amoxicillin with clavulanate on the composition and quantity of bacteria in the tonsils of children with recurrent tonsillitis. A multicenter randomized clinical trial in Auckland, New Zealand was undertaken between August 1, 2017, and June 30, 2018. Sixty children undergoing tonsillectomy for the indication of recurrent tonsillitis were recruited for this study. Following random allocation, 30 participants were prescribed amoxicillin with clavulanate for the week before surgery. The remaining 30 received no antibiotics. Immediately following surgery, the crypts of the right and left tonsils were swabbed. Bacterial 16S rRNA gene-targeted amplicon sequencing and histological techniques were utilized. In the control group, there were significantly higher relative abundances of Haemophilus, Streptococcus, Neisseria, and Porphyromonas. Members from the genera Fusobacterium and Treponema were found to be significantly more abundant in the antibiotic group. There were no significant differences in the absolute quantities of bacteria between the groups. Microscopic examination found fewer bacterial microcolonies present in the tonsillar crypts of participants in the antibiotic group. Streptococcus pyogenes was not present in these bacterial microcolonies. These results suggest that a single course of antibiotics has a significant impact on the tonsil microbiota composition. The duration of this effect and the effect that the altered microbiome has on the course of the condition need to be determined. IMPORTANCE Several studies have identified the presence of multiple pathogenic bacteria in hyperplastic adenoids and palatine tonsils. However, there are currently no studies that utilize this technology to investigate the effect of oral antibiotics in children with recurrent tonsillitis on the tonsillar microbiome. This is the first study to investigate the effect of antibiotics on the microbiome of tonsillar tissue in children with recurrent tonsillitis using molecular techniques. This study has shown that participants who received amoxicillin with clavulanate immediately before tonsillectomy had a significantly reduced number of bacterial taxa commonly associated with recurrent tonsillitis, as well as the number of bacterial microcolonies observed in the tonsillar crypts. This novel finding suggests that either the effect of antibiotics is not sustained or that they are not an effective treatment for recurrent tonsillitis.


Subject(s)
Microbiota , Tonsillitis , Child , Humans , Amoxicillin/therapeutic use , Clavulanic Acid/pharmacology , Clavulanic Acid/therapeutic use , RNA, Ribosomal, 16S/genetics , Tonsillitis/drug therapy , Tonsillitis/surgery , Tonsillitis/microbiology , Microbiota/genetics , Anti-Bacterial Agents/therapeutic use , Streptococcus pyogenes/genetics
11.
Water Res ; 222: 118858, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35872519

ABSTRACT

The framework, model and methods of Nürnberg were applied and evaluated in Lough Neagh and 19 other lakes in order to establish inflow phosphorus concentrations that support target lake values. Supporting concentrations, in the absence of an internal load, were derived and the effect of uncertainty in the model retention coefficient was relatively small, ±11-20 % in Lough Neagh and an average (n = 17) of ±9.7 % in the other lakes. There was further support for the model and methods from an independent estimate of the net internal load in Lough Neagh (13 % difference) and from another model in the other lakes (Supporting concentrations, which should be lower, were by an average of 11 mg P m-3). In the framework, steady state with the phosphorus load is assumed, but, based on a generic lake model, is not likely if the hydraulic residence time>0.5-0.8 yr and should lead to a decrease in phosphorus retention, which was found during three periods in Lough Neagh. Based on a compilation of internal load recovery times from 23 lakes in the literature, it could take between 8 and 20 years for lakes with an internal load to approach their targets.


Subject(s)
Lakes , Phosphorus , Environmental Monitoring , Eutrophication , Nitrogen , Phosphorus/analysis
12.
Front Pharmacol ; 13: 840323, 2022.
Article in English | MEDLINE | ID: mdl-35770097

ABSTRACT

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.

13.
Int J Pediatr Otorhinolaryngol ; 157: 111128, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35421675

ABSTRACT

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.


Subject(s)
Pharyngeal Diseases , Sleep Apnea Syndromes , Tonsillectomy , Tonsillitis , Child , Humans , Hyperplasia/pathology , Immunoglobulin E , Palatine Tonsil/pathology , Pharyngeal Diseases/pathology , Tonsillitis/microbiology
14.
Clin Case Rep ; 10(3): e05602, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35356174

ABSTRACT

Common variable immunodeficiency (CVID) is a primary immunodeficiency disease. We present a case of a patient with CVID complicated by rhinosinusitis with granulomatous inflammation. Treatment for this patient was challenging with regards recognition of the granulomatous manifestation as well as treatment in the setting immunodeficiency and was ultimately unsuccessful.

15.
J Allergy Clin Immunol ; 149(5): 1504-1512, 2022 05.
Article in English | MEDLINE | ID: mdl-35217148

ABSTRACT

Rhinosinusitis is one of the most common reasons for adult outpatient antibiotic prescriptions, though there is little clinical evidence to support this practice, especially for chronic rhinosinusitis. Despite considerable research, the etiology of chronic rhinosinusitis, including the pathogenic role of microbes, remains poorly understood. Rigorous studies of the efficacy of antibiotic treatment of chronic sinusitis are surprisingly few in number and the results are somewhat conflicting. This review article will review the rationales for and against the treatment of chronic rhinosinusitis with antibiotics, based on current evidence and understanding of pathophysiology, and will also summarize the current guidelines.


Subject(s)
Rhinitis , Sinusitis , Adult , Anti-Bacterial Agents/therapeutic use , Chronic Disease , Humans , Rhinitis/drug therapy , Sinusitis/drug therapy
16.
Pharm Res ; 39(2): 317-327, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35137359

ABSTRACT

BACKGROUND: Optimising intranasal distribution and retention of topical therapy is essential for effectively managing patients with chronic rhinosinusitis, including those that have had functional endoscopic sinus surgery (FESS). This study presents a new technique for quantifying in vitro experiments of fluticasone propionate deposition within the sinuses of a 3D-printed model from a post-FESS patient. METHODS: Circular filter papers were placed on the sinus surfaces of the model. Deposition of fluticasone on the filter paper was quantified using high-performance liquid chromatography (HPLC) assay-based techniques. The deposition patterns of two nasal drug delivery devices, an aqueous nasal spray (Flixonase) and metered dose inhaler (Flixotide), were compared. The effects of airflow (0 L/min vs. 12 L/min) and administration angle (30° vs. and 45°) were evaluated. RESULTS: Inhaled airflow made little difference to sinus deposition for either device. A 45° administration angle improved frontal sinus deposition with the nasal spray and both ethmoidal and sphenoidal deposition with the inhaler. The inhaler provided significantly better deposition within the ethmoid sinuses (8.5x) and within the maxillary sinuses (3.9x) compared with the nasal spray under the same conditions. CONCLUSION: In the post-FESS model analysed, the inhaler produced better sinus deposition overall compared with the nasal spray. The techniques described can be used and adapted for in vitro performance testing of different drug formulations and intranasal devices under different experimental conditions. They can also help validate computational fluid dynamics modelling and in vivo studies.


Subject(s)
Fluticasone/administration & dosage , Glucocorticoids/administration & dosage , Models, Anatomic , Paranasal Sinuses/metabolism , Administration, Inhalation , Drug Compounding , Female , Fluticasone/chemistry , Fluticasone/metabolism , Glucocorticoids/chemistry , Glucocorticoids/metabolism , Humans , Metered Dose Inhalers , Middle Aged , Nasal Sprays , Paranasal Sinuses/anatomy & histology , Paranasal Sinuses/surgery , Printing, Three-Dimensional , Tissue Distribution , Transanal Endoscopic Surgery
17.
Sci Rep ; 11(1): 21940, 2021 11 09.
Article in English | MEDLINE | ID: mdl-34753993

ABSTRACT

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.


Subject(s)
Sinusitis/microbiology , Staphylococcus aureus/isolation & purification , Adult , Carrier State , Chronic Disease , Cross-Sectional Studies , Female , Genes, Bacterial , Humans , Male , Middle Aged , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics
18.
Front Cell Infect Microbiol ; 11: 585625, 2021.
Article in English | MEDLINE | ID: mdl-34595125

ABSTRACT

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.


Subject(s)
Paranasal Sinuses , Sinusitis , Animals , Chronic Disease , Humans , Inflammation , Nasal Cavity , Paranasal Sinuses/diagnostic imaging , Quality of Life , Rabbits , Sinusitis/diagnostic imaging
19.
Int J Otolaryngol ; 2021: 7428955, 2021.
Article in English | MEDLINE | ID: mdl-34567126

ABSTRACT

The purpose of this review is to summarise contemporary knowledge of sinonasal tissue remodelling during chronic rhinosinusitis (CRS), a chronic disease involving long-term inflammation of the paranasal sinuses and nasal passage. The concept of tissue remodelling has significant clinical relevance because of its potential to cause irreversibility in chronic airway tissues. Recent studies have indicated that early surgical treatment of CRS may improve clinical outcome. Tissue remodelling has been described in the literature extensively with no consensus on how remodelling is defined. This review describes various factors implicated in establishing remodelling in sinonasal tissues with a special mention of asthma as a comorbid condition. Some of the main histological features of remodelling include basement membrane thickening and collagen modulation. This may be an avenue of research with regard to targeted therapy against remodelling in CRS.

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