Biofilms in chronic rhinosinusitis with polyps: is eradication possible?

The Mechanism of Action and Clinical Efficacy of Low-Dose Long-Term Macrolide Therapy in Chronic Rhinosinusitis

Various chronic inflammatory airway diseases can be treated with low-dose, long-term (LDLT) macrolide therapy. LDLT macrolides can be one of the therapeutic options for chronic rhinosinusitis (CRS) due to their immunomodulatory and anti-inflammatory actions. Currently, various immunomodulatory mechanisms of the LDLT macrolide treatment have been reported, as well as their antimicrobial properties. Several mechanisms have already been identified in CRS, including reduced cytokines such as interleukin (IL)-8, IL-6, IL-1β, tumor necrosis factor-α, transforming growth factor-β, inhibition of neutrophil recruitment, decreased mucus secretion, and increased mucociliary transport. Although some evidence of effectiveness for CRS has been published, the efficacy of this therapy has been inconsistent across clinical studies. LDLT macrolides are generally believed to act on the non-type 2 inflammatory endotype of CRS. However, the effectiveness of LDLT macrolide treatment in CRS is still controversial. Here, we reviewed the immunological mechanisms related to CRS in LDLT macrolide therapy and the treatment effects according to the clinical situation of CRS.

Long-term, low-dose macrolide antibiotic treatment in pediatric chronic airway diseases

Macrolide antibiotics are one of the most commonly used broad-spectrum antibiotics. They have an inhibitory effect on a variety of respiratory pathogens; besides, they have non-anti-infective effects, including anti-inflammatory, regulating airway secretion, immune regulation, and other effects. A growing number of studies have shown that the non-anti-infective effects of macrolides have important and potential value in the treatment of pediatric chronic airway diseases; the therapy was described as "long-term, low-dose usage"; unfortunately, there is no guideline or consensus that applies to children. To better carry out the mechanism and clinical research of non-anti-infective effect and promote its rational use in children, the authors summarize the evidence of the usage of long-term, low-dose macrolide antibiotic therapy (LLMAT) in the treatment of chronic airway diseases in children and the progress in recent years. IMPACT: This review summarizes the evidence (mostly in recent 5 years) of the usage of long-term, low-dose macrolide antibiotic therapy in the treatment of chronic airway diseases. The recent studies and guidelines support and enrich the point that long-term, low-dose macrolide antibiotic therapy has potential benefit for children with severe asthma, CF, non-CF bronchiectasis, and BO, which provides clinical references and is of clinical interest. Long-term, low-dose macrolide antibiotic therapy has good safety, and no serious events have been reported; however, potential cardiac side effects and macrolide resistance should be clinically noted.

Novel strategies for inhibition of bacterial biofilm in chronic rhinosinusitis

An important role has been recently reported for bacterial biofilm in the pathophysiology of chronic diseases, such as chronic rhinosinusitis (CRS). CRS, affecting sinonasal mucosa, is a persistent inflammatory condition with a high prevalence around the world. Although the exact pathological mechanism of this disease has not been elicited yet, biofilm formation is known to lead to a more significant symptom burden and major objective clinical indicators. The high prevalence of multidrug-resistant bacteria has severely restricted the application of antibiotics in recent years. Furthermore, systemic antibiotic therapy, on top of its insufficient concentration to eradicate bacteria in the sinonasal biofilm, often causes toxicity, antibiotic resistance, and an effect on the natural microbiota, in patients. Thus, coming up with alternative therapeutic options instead of systemic antibiotic therapy is emphasized in the treatment of bacterial biofilm in CRS patients. The use of topical antibiotic therapy and antibiotic eluting sinus stents that induce higher antibiotic concentration, and decrease side effects could be helpful. Besides, recent research recognized that various natural products, nitric oxide, and bacteriophage therapy, in addition to the hindered biofilm formation, could degrade the established bacterial biofilm. However, despite these improvements, new antibacterial agents and CRS biofilm interactions are complicated and need extensive research. Finally, most studies were performed in vitro, and more preclinical animal models and human studies are required to confirm the collected data. The present review is specifically discussing potential therapeutic strategies for the treatment of bacterial biofilm in CRS patients.

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.

Symptom assessment after nasal irrigation with xylitol in the postoperative period of endonasal endoscopic surgery

INTRODUCTION

Chronic rhinosinusitis is an inflammatory condition of the nasal cavity and the paranasal sinuses that requires multifactorial treatment. Xylitol can be employed with nasal irrigation and can provide better control of the disease.

OBJECTIVE

To evaluate the association between the effects of nasal lavage with saline solution compared to nasal lavage with a xylitol solution.

METHODS

Fifty-two patients, divided into two groups (n = 26 in the "Xylitol" group and n = 26 in the "Saline solution" group) answered questionnaires validated in Portuguese (NOSE and SNOT-22) about their nasal symptoms and general symptoms, before and after endonasal endoscopic surgery and after a period of 30 days of nasal irrigation.

RESULTS

The "Xylitol" group showed significant improvement in pain relief and nasal symptom reduction after surgery and nasal irrigation with xylitol solution (p < 0.001). The "Saline solution" group also showed symptom improvement, but on a smaller scale.

CONCLUSION

This study suggests that the xylitol solution can be useful in the postoperative period after endonasal endoscopic surgery, because it leads to a greater reduction in nasal symptoms.

The Role of Macrolides and Doxycycline in Chronic Rhinosinusitis

Antibiotic therapy has become an important adjunct in the management of recalcitrant chronic rhinosinusitis (CRS) because of some antibiotics' immunomodulatory properties even at subtherapeutic antimicrobial levels. Macrolide antibiotics, such as clarithromycin and azithromycin, decrease production of proinflammatory cytokines, impair neutrophil recruitment, inhibit bacterial biofilm formation, and improve mucus quality. Doxycycline, a tetracycline antibiotic, inhibits the activity of matrix metalloproteinases in CRS with nasal polyposis. This article reviews the clinical applications for macrolide and doxycycline use in CRS, considerations for dosing and duration of treatment, and important side effects and drug interactions associated with these medications.

Effect of Postoperative Xylitol Nasal Irrigation on Patients with Sinonasal Diseases

OBJECTIVE

To examine the effect of xylitol nasal irrigation in a large sample size of patients who had undergone nasal surgery.

STUDY DESIGN

Double-blinded randomized controlled crossover study.

SETTING

Tertiary referral center.

METHODS

The study included 100 patients with sinonasal disease who underwent endoscopic sinus surgery (ESS), septoplasty, or both concurrently. To identify patients with allergic sensitization, serum-specific immunoglobulin E levels were measured. Nasal symptoms were evaluated with the NOSE (Nasal Obstruction Symptoms Evaluation) and SNOT-20 (Sino-Nasal Outcome Test-20) and via visual analog scale (VAS) scores.

RESULTS

In the ESS group (n = 34), the general nasal symptom score evaluated by the SNOT-20 showed significantly greater improvement in the xylitol group versus the saline group ( P = .022). VAS symptom scores for sneezing ( P = .003), headache ( P = .02), and facial pain ( P = .037) were also more improved in the xylitol group. In the septoplasty group (n = 39), the VAS score for nasal stuffiness showed a significantly greater improvement in the xylitol group when compared with the saline irrigation group ( P = .001). Among the patients with allergic sensitization (n = 31), rhinorrhea symptoms improved significantly more in the xylitol group than in the saline group ( P = .024). The preference survey showed that more than half of the patients in each surgical group preferred xylitol irrigation.

CONCLUSION

We found that xylitol nasal irrigation was useful in postoperative ESS and septoplasty care. For patients with allergic sensitization, rhinorrhea showed greater improvement in the xylitol group than in the saline group.

Macrolide antibiotics in the treatment of chronic rhinosinusitis: evidence from a meta-analysis

Background

The purpose of this study was to systematically assess the subjective and objective outcomes of macrolide therapy for chronic rhinosinusitis (CRS).

Methods

PubMed, Embase and Cochrane databases were searched for clinical trials detailing the effects of macrolide therapy in patients with CRS and published up to December 2017. Sino-Nasal Outcome Test (SNOT), endoscopic scores and computed tomography scans (CT) scores were assessed by mean difference (MD) or standardized mean difference (SMD) with 95% confidence interval. Subgroup analyses were performed to evaluate the source of heterogeneity according to study design and geographic locations. I² metric was used to assess the heterogeneity.

Results

Seven randomised clinical trials (RCTs) and four cohort trials meeting pre-determined selection criteria were enrolled in this meta-analysis. Assessment of the findings for SNOT after 12 weeks' macrolide treatment demonstrated a significant improvement in subgroup of trials in Asian patients (SMD =-0.51; 95% CI: -0.96, -0.02; P=0.04), but not in non-Asians (SMD =-0.01; 95% CI: -0.65, 0.63; P=0.98). At 12 or 24 weeks' visit no significant difference in SNOT was noted compared with control group, either in RCTs or cohort trials subgroups. However, findings for endoscopic scores were found to be significantly improved compared to placebo in the subgroup of non-RCT studies after 8 weeks (SMD =-0.77; 95% CI: -1.07, -0.46; P<0.00001) and 12 weeks (SMD=-1.40; 95% CI: -1.97, -0.82; P<0.00001) of macrolide therapy. Similarly, findings for CT scores showed significant improvements in CT scores compared to baseline after 12 weeks' treatment (MD=-5.81; 95% CI: -8.10, -3.52; P<0.00001) in cohort trials.

Conclusions

Macrolide therapy can significantly improve endoscopic and CT scores in CRS patients, compared to baseline. Further well-designed studies are needed to confirm the efficacy and safety of macrolides in CRS treatment.

Understanding the Role of Biofilms and Superantigens in Chronic Rhinosinusitis

PURPOSE OF REVIEW

This review explores recent discoveries in our understanding of how biofilms and superantigens contribute to the pathogenesis of chronic rhinosinusitis (CRS). It also examines clinical implications and novel treatment approaches for biofilm associated CRS.

RECENT FINDINGS

While the role of biofilms in CRS has been studied for 14 years, research interest has now turned toward elucidating new methods of biofilm detection, microbial diversity, and novel treatment approaches. Recent studies on biofilm superantigens aim to clarify the immunological mechanisms of upper airway inflammation, particularly the type-2 response seen in nasal polyposis.

SUMMARY

Biofilms are a topic of research interest for their role in the pathogenesis of chronic rhinosinusitis, particularly when they elute superantigens. New studies on this topic focus on the molecular and cellular mechanisms at play.

Nasal cytology: Methodology with application to clinical practice and research

Nasal cytology is an easy, cheap, non-invasive and point-of-care method to assess nasal inflammation and disease-specific cellular features. By means of nasal cytology, it is possible to distinguish between different inflammatory patterns that are typically associated with specific diseases (ie, allergic and non-allergic rhinitis). Its use is particularly relevant when other clinical information, such as signs, symptoms, time-course and allergic sensitizations, is not enough to recognize which of the different rhinitis phenotypes is involved; for example, it is only by means of nasal cytology that it is possible to distinguish, among the non-allergic rhinitis, those characterized by eosinophilic (NARES), mast cellular (NARMA), mixed eosinophilic-mast cellular (NARESMA) or neutrophilic (NARNE) inflammation. Despite its clinical usefulness, cheapness, non-invasiveness and easiness, nasal cytology is still underused and this is at least partially due to the fact that, as far as now, there is not a consensus or an official recommendation on its methodological issues. We here review the scientific literature about nasal cytology, giving recommendations on how to perform and interpret nasal cytology.

Antibiofilm effects of amoxicillin-clavulanic acid and levofloxacin in patients with chronic rhinosinusitis with nasal polyposis

PURPOSE

Microbial biofilms have been implicated in the pathogenesis of chronic rhinosinusitis with nasal polyposis (CRSwNP). The aim of our study was to evaluate in vitro effects of amoxicillin-clavulanic acid and levofloxacin on biofilm formation by bacterial species isolated from sinus tissue in patients with CRSwNP.

METHODS

The sinus mucosal specimens were harvested from the upper parts and roof of ethmoid cavity of 48 patients with CRSwNP. Each sample was washed thoroughly in three separate beakers of sterile saline to remove any planktonic bacteria and further subjected to microbiology analysis. The biofilm-forming capacity of isolated strains was detected by microtiter-plate method and the effects of subinhibitory (1/2× to 1/16× MIC) and suprainhibitory concentrations (4, 8, 16, 32, and 64 µg/ml) of amoxicillin-clavulanic acid and levofloxacin on biofilm production were investigated.

RESULTS

Bacterial strains were isolated in 42 (87.5%) patients: one microorganism in 80.9% and two microorganisms in 19.1% of patients. The most prevalent bacteria in CRSwNP biofilms were Staphylococcus epidermidis (34%) and S. aureus (28%) followed by S. haemolyticus (12%), Pseudomonas aeruginosa (8%), Moraxella catarrhalis (6%), Streptococcus pneumoniae (6%), and other staphylococci (6%). Subinhibitory concentrations of amoxicillin-clavulanic acid and levofloxacin significantly reduced biofilm formation (p < 0.01 and p < 0.05, respectively), with better efficacy of amoxicillin-clavulanic acid (1/2-1/8× MIC) on staphylococci and levofloxacin (1/2- 1/4× MIC) on M. catarrhalis and P. aeruginosa biofilm formation. Suprainhibitory concentrations of both tested antibiotics (4-64 µg/ml) significantly eradicated mature biofilms of staphylococci (p < 0.01). The effect of levofloxacin on eradication of staphylococcal biofilms was more noticeable, compared to the effect of amoxicillin-clavulanic acid (p < 0.01). Suprainhibitory concentrations of both tested antibiotics had no effect on eradication of previously formed M. catarrhalis and P. aeruginosa biofilms (p > 0.05).

CONCLUSIONS

The amoxicillin-clavulanic acid and levofloxacin are shown to be potent antibiofilm agents in patients with CRSwNP. The effects of tested compounds depend on bacterial species and the volume of formed biofilm.

Survey about the use of clarithromycin in an ENT outpatient department of a tertiary hospital

We undertook this survey about the use of clarithromycin in the Ear, Nose, and Throat (ENT) Outpatient Department of Fudan University Hospital to understand its utilization patterns and rational use. A survey of prescriptions given to outpatients was carried out, and detailed information of the patients, including age, sex, diagnosis, combined medication, and other information, was recorded in Excel spreadsheets. The rationale for each prescription was evaluated retrospectively. Based on our analysis, 82.5% of the clarithromycin prescriptions were for the treatment of rhinosinusitis. It was found that the parameters for the diagnosis of this condition were surprisingly broad and should have been more specific. In addition, the clarithromycin dosage regimen varied in clinical practice. For chronic rhinosinusitis, the duration of treatment was between 8 and 16 days, which was not sufficient. Moreover, clarithromycin was prescribed along with considerable numbers of pharmacotherapeutic anti-allergic drugs. Our survey indicated that improvements in the quality of clarithromycin prescriptions in otolaryngology outpatients should be made. Furthermore, the importance of medical education to patients should be emphasized. In addition, the interaction between clarithromycin and other anti-allergic drugs requires further investigation.

Systemic and topical antibiotics for chronic rhinosinusitis

BACKGROUND

This review is one of six looking at the primary medical management options for patients with chronic rhinosinusitis.Chronic rhinosinusitis is common and is characterised by inflammation of the lining of the nose and paranasal sinuses leading to nasal blockage, nasal discharge, facial pressure/pain and loss of sense of smell. The condition can occur with or without nasal polyps. Systemic and topical antibiotics are used with the aim of eliminating infection in the short term (and some to reduce inflammation in the long term), in order to normalise nasal mucus and improve symptoms.

OBJECTIVES

To assess the effects of systemic and topical antibiotics in people with chronic rhinosinusitis.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; CENTRAL (2015, Issue 8); MEDLINE; EMBASE; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 29 September 2015.

SELECTION CRITERIA

Randomised controlled trials (RCTs) with a follow-up period of at least three months comparing systemic or topical antibiotic treatment to (a) placebo or (b) no treatment or (c) other pharmacological interventions.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcomes were disease-specific health-related quality of life (HRQL), patient-reported disease severity and the commonest adverse event - gastrointestinal disturbance. Secondary outcomes included general HRQL, endoscopic nasal polyp score, computerised tomography (CT) scan score and the adverse events of suspected allergic reaction (rash or skin irritation) and anaphylaxis or other very serious reactions. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics.

MAIN RESULTS

We included five RCTs (293 participants), all of which compared systemic antibiotics with placebo or another pharmacological intervention.The varying study characteristics made comparison difficult. Four studies recruited only adults and one only children. Three used macrolide, one tetracycline and one a cephalosporin-type antibiotic. Three recruited only patients with chronic rhinosinusitis without nasal polyps, one recruited patients with chronic rhinosinusitis with nasal polyps and one had a mixed population. Three followed up patients for 10 to 12 weeks after treatment had finished. Systemic antibiotics versus placebo Three studies compared antibiotics with placebo (176 participants).One study (64 participants, without polyps) reported disease-specific HRQL using the SNOT-20 (0 to 5, 0 = best quality of life). At the end of treatment (three months) the SNOT-20 score was lower in the group receiving macrolide antibiotics than the placebo group (mean difference (MD) -0.54 points, 95% confidence interval (CI) -0.98 to -0.10), corresponding to a moderate effect size favouring antibiotics (moderate quality evidence). Three months after treatment, it is uncertain if there was a difference between groups.One study (33 participants, with polyps) provided information on gastrointestinal disturbances and suspected allergic reaction (rash or skin irritation) after a short course of tetracycline antibiotic compared with placebo. We are very uncertain if antibiotics were associated with an increase in gastrointestinal disturbances (risk ratio (RR) 1.36, 95% CI 0.22 to 8.50) or skin irritation (RR 6.67, 95% CI 0.34 to 128.86) (very low quality evidence). Systemic antibiotics plus saline irrigation and intranasal corticosteroids versus placebo plus saline irrigation and intranasal corticosteroids One study (60 participants, some with and some without polyps) compared a three-month course of macrolide antibiotic with placebo; all participants also used saline irrigation and 70% used intranasal corticosteroids. Disease-specific HRQL was reported using SNOT-22 (0 to 110, 0 = best quality of life). Data were difficult to interpret (highly skewed and baseline imbalances) and it is unclear if there was an important difference at any time point (low quality evidence). To assess patient-reported disease severity participants rated the effect of treatment on a five-point scale (-2 for "desperately worse" to 2 for "cured") at the end of treatment (three months). For improvement in symptoms there was no difference between the antibiotics and placebo groups; the RR was 1.50 (95% CI 0.81 to 2.79; very low quality evidence), although there were also slightly more people who felt worse after treatment in the antibiotics group. There was no demonstrable difference in the rate of gastrointestinal disturbances between the groups (RR 1.07, 95% CI 0.16 to 7.10). General HRQL was measured using the SF-36. The authors stated that there was no difference between groups at the end of treatment (12 weeks) or two weeks later. Systemic antibiotics versus intranasal corticosteroids One study (43 participants, without polyps) compared a three-month course of macrolide antibiotic with intranasal corticosteroids. Patient-reported disease severity was assessed using a composite symptom score (0 to 40; 0 = no symptoms). It is very uncertain if there was a difference as patient-reported disease severity was similar between groups (MD -0.32, 95% CI -2.11 to 1.47; low quality evidence). Systemic antibiotics versus oral corticosteroids One study (28 participants, with polyps) compared a short course of tetracycline antibiotic (unclear duration, ˜20 days) with a 20-day course of oral corticosteroids. We were unable to extract data on any of the primary efficacy outcomes. It is uncertain if there was a difference ingastrointestinal disturbances (RR 1.00, 95% CI 0.16 to 6.14) or skin irritation (RR 2.00, 95% CI 0.20 to 19.62) as the results for these outcomes were similar between groups (very low quality evidence).

AUTHORS' CONCLUSIONS

We found very little evidence that systemic antibiotics are effective in patients with chronic rhinosinusitis. We did find moderate quality evidence of a modest improvement in disease-specific quality of life in adults with chronic rhinosinusitis without polyps receiving three months of a macrolide antibiotic. The size of improvement was moderate (0.5 points on a five-point scale) and only seen at the end of the three-month treatment; by three months later no difference was found.Despite a general understanding that antibiotics can be associated with adverse effects, including gastrointestinal disturbances, the results in this review were very uncertain because the studies were small and few events were reported.No RCTs of topical antibiotics met the inclusion criteria.More research in this area, particularly evaluating longer-term outcomes and adverse effects, is required.

Role of biofilm in children with recurrent upper respiratory tract infections

Recurrent respiratory tract infections (RRTIs) are very common in children and a major challenge for pediatricians. In the last few years, bacterial biofilms have been linked to RRTIs and antibiotic resistance, and have raised serious concerns regarding the therapeutic management of recurrent middle ear diseases, chronic rhinosinusitis, and recurrent pharyngotonsillitis. This paper aims to review the new insights into biofilm-related upper respiratory tract infections in children and possible therapeutic strategies. It focuses on the clinical implications for recurrent disease and on studies in pediatric patients. Analysis of the literature showed that the involvement of bacterial biofilm in recurrent upper airway tract infections is an emerging problem that may lead to serious concerns about infection control. Despite the large amount of research within this field, detailed insight into the complex structure of bacterial biofilms and the ultrastructural and biochemical mechanisms responsible for its evasion of the immune system and resistance to treatments is currently lacking. In the future, additional emphasis should be placed on biofilm management as a component of therapeutic strategies. This goal can be attained by finding feasible methods for detecting biofilms in vivo and identifying effective methods for administering treatments that eradicate preexisting bacterial biofilms or hinder bacterial adhesion to respiratory cells.