Low-dose and long-term azithromycin significantly decreases Staphylococcus aureus in the microbiome of refractory CRS patients

Systematic Review and Meta-analysis: Macrolide in the Treatment of Chronic Rhinosinusitis After Endoscopic Sinus Surgery

OBJECTIVES

To evaluate the efficacy and safety of macrolide antibiotics therapy in patients with chronic rhinosinusitis (CRS) receiving endoscopic sinus surgery.

DATA SOURCES

PubMed, Web of Science, Embase, and Cochrane Library.

REVIEW METHODS

The electronic databases were comprehensively searched on June 2, 2022, for randomized controlled trials on macrolide antibiotics in the treatment of patients undergoing CRS endoscopic surgery. The primary outcome measures were the sinonasal outcome test (SNOT) score and the visual analog scale (VAS) score. The secondary outcome measures were the nasal endoscopy score (NES), the sinus computed tomography score, and adverse events.

RESULTS

A total of 8 studies were included, involving 606 patients who used macrolide for a long time. Meta-analysis showed that no significant difference was observed in SNOT (standardized mean difference [SMD] = -0.13; 95% confidence interval [CI]: -0.38 to 0.13, I2  = 0%) and VAS (SMD = -0.10; 95% CI, -0.88 to 0.68, I2  = 81%) between the macrolide and placebo groups. However, macrolide outperformed the placebo in improving NES (SMD = -0.32; 95% CI, -0.62 to -0.03, I2  = 21%). The use of macrolide did not increase the incidence of adverse events.

CONCLUSION

Long-term use of macrolide after CRS surgery may not significantly improve the quality of life and disease severity of the patients but may play a role in improving postoperative NES in patients with CRS. There is still no sufficient evidence to determine whether the disease phenotype of CRS or the patient's race will affect the efficacy of long-term use of macrolide after CRS.

Utilization of Transcriptomic Profiling to Identify Molecular Markers Predicting Successful Recovery Following Endoscopic Sinus Surgery for Chronic Rhinosinusitis

OBJECTIVES

Successful recovery from chronic rhinosinusitis (CRS) following endoscopic sinus surgery (ESS) can be characterized by minimal presence of symptoms and absence of disease on endoscopy. However, molecular markers of surgical success remain to be characterized. These could allow for better tailoring of perioperative therapy. This study aims to identify novel molecular markers associated with surgery responsive patient.

STUDY DESIGN

Prospective cohort study.

SETTING

Single academic hospital center.

METHOD

One hundred eighteen consecutive patients with CRS at high risk of recurrence after surgery were followed prospectively following ESS in an academic medical center. Symptomatic and endoscopic outcomes were assessed at 4 months, with success rigorously defined subjectively as minimal or no symptoms (no symptom greater than 1 on an ordinal scale of 0-3) and objectively by the absence of nasal polyposis on sinus cavity endoscopy and Lund-Kennedy endoscopic edema score no greater than 1. Samples were obtained at the time of surgery and at 4-month postoperatively. Changes associated with surgery were determined by gene expression profiling using Affymetrix's Clariom S Human HT arrays.

RESULTS

Successful ESS was characterized by a mild upregulation in Type 1 inflammation, upregulation of cell cycle progression, and epithelial barrier and proliferation-associated genes and pathways. ESS failure was associated to very high levels of Type 1 inflammation along with downregulation of epithelial barrier function and regeneration genes and pathways.

CONCLUSION

Successful recovery from ESS involves restoration of epithelial function and regulated activation of Type 1 inflammation. Excessively elevated Type 1 inflammation is associated with epithelial barrier dysfunction.

The Impact of Antibiotics and Steroids on the Nasal Microbiome in Patients with Chronic Rhinosinusitis: A Systematic Review According to PICO Criteria

BACKGROUND

The nasal microbiome represents the main environmental factor of the inflammatory process in chronic rhinosinusitis (CRS). Antibiotics and steroids constitute the mainstay of CRS therapies. However, their impact on microbial communities needs to be better understood. This systematic review summarizes the evidence about antibiotics' and steroids' impact on the nasal microbiota in patients with CRS.

METHODS

The search strategy was conducted in accordance with the PRISMA guidelines for systematic reviews. The authors searched all papers in the three major medical databases (PubMed, Scopus, and Cochrane Library) using the PICO tool (population, intervention, comparison, and outcomes). The search was carried out using a combination of the key terms "Microbiota" or "Microbiome" and "Chronic Rhinosinusitis".

RESULTS

Overall, 402 papers were identified, and after duplicate removal (127 papers), excluding papers off-topic (154) and for other structural reasons (110), papers were assessed for eligibility; finally, only 11 papers were included and summarized in the present systematic review. Some authors used only steroids, other researchers used only antibiotics, and others used both antibiotics and steroids. With regard to the use of steroids as exclusive medical treatment, topical mometasone and budesonide were investigated. With regard to the use of antibiotics as exclusive medical treatments, clarithromycin, doxycycline, roxithromycin, and amoxicillin clavulanate were investigated. Regarding the use of both antibiotics and steroids, two associations were investigated: systemic prednisone combined with amoxicillin clavulanate and topical budesonide combined with azithromycin.

CONCLUSIONS

The impact that therapies can have on the nasal microbiome of CRS patients is very varied. Further studies are needed to understand the role of the nasal microbiome, prevent CRS, and improve therapeutic tools for personalized medicine tailored to the individual patient.

Azithromycin Mechanisms of Action in CRS Include Epithelial Barrier Restoration and Type 1 Inflammation Reduction

OBJECTIVE

Previous in vitro transcriptomic profiling suggests azithromycin exerts its effects in patients with chronic rhinosinusitis (CRS) via modulation of type 1 inflammation and restoration of epithelial barrier function. We wished to verify these postulated effects using in vitro models of epithelial repair and in vivo transcriptional profiling.

STUDY DESIGN

Functional effects of azithromycin in CRS were verified using in vitro models of wounding. The mechanism of the effect of azithromycin was assessed in vivo using transcriptomic profiling.

SETTING

Academic medical center.

METHODS

Effects of azithromycin on the speed of epithelial repair were verified in a wounding model using primary nasal epithelial cells (pNEC) from CRS patients. Nasal brushings collected pre-and posttreatment during a placebo-controlled trial of azithromycin for CRS patients unresponsive to surgery underwent transcriptomic profiling to identify implicated pathways.

RESULTS

Administration of azithromycin improved the wound healing rates in CRS pNECs and prevented the negative effect of Staphylococcus aureus on epithelial repair. In vivo, response to azithromycin was associated with downregulation in pathways of type 1 inflammation, and upregulation of pathways implicated in the restoration of the cell cycle.

CONCLUSION

Restoration of healthy epithelial function may represent a major mode of action of azithromycin in CRS. In vitro models show enhanced epithelial repair, while in vivo transcriptomics shows downregulation of pathways type 1 inflammation accompanied by upregulation of DNA repair and cell-cycle pathways. The maximal effect in patients with high levels of type 1-enhanced inflammation suggests that azithromycin may represent a novel therapeutic option for surgery-unresponsive CRS patients.

Pathophysiology and management of Staphylococcus aureus in nasal polyp disease

INTRODUCTION

Staphylococcus aureus (S. aureus) is a common pathogen that frequently colonizes the sinonasal cavity. Recent studies demonstrated the essential role of Staphylococcus aureus in the pathophysiology of uncontrolled severe chronic rhinosinusitis with nasal polyps (NP) by initiating an immune response to the germ and its products, resulting in type 2 inflammation.

AREAS COVERED

This review aims to summarize the evidence for the role of S. aureus in the development of NP disease including S. aureus-related virulence factors, the pathophysiologic mechanisms used by S. aureus, and the synergistic effects of S. aureus and other pathogens. It also describes the current management of S. aureus associated with NPs as well as potential therapeutic strategies that are used in clinical practice.

EXPERT OPINION

S. aureus is able to damage the nasal mucosal epithelial barrier, impair the clearance of the host immune system, and trigger adaptive and innate immune reactions which lead to the formation of inflammation and nasal polyp growth. Further studies should focus on the development of novel therapeutic strategies, such as biologics, bacteriophages, probiotics, and nanomedicine, which could be used to treat S. aureus and its immunological consequences in the future.

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.

The Effect of Radiation and Chemoradiation Therapy on the Head and Neck Mucosal Microbiome: A Review

Radiation (RT) and chemoradiation therapy (CRT) play an essential role in head and neck cancer treatment. However, both cause numerous side effects in the oral cavity, paranasal sinuses, and pharynx, having deleterious consequences on patients’ quality of life. Concomitant with significant advances in radiation oncology, much attention has turned to understanding the role of the microbiome in the pathogenesis of treatment-induced tissue toxicity, to ultimately explore microbiome manipulation as a therapeutic intervention. This review sought to discuss current publications investigating the impact of RT and CRT-induced changes on the head and neck microbiome, using culture-independent molecular methods, and propose opportunities for future directions. Based on 13 studies derived from a MEDLINE, EMBASE, and Web of Science search on November 7, 2021, use of molecular methods has uncovered various phyla and genera in the head and neck microbiome, particularly the oral microbiome, not previously known using culture-based methods. However, limited research has investigated the impact of RT/CRT on subsites other than the oral cavity and none of the studies aimed to examine the relationship between the head and neck microbiome and treatment effectiveness. Findings from this review provide helpful insights on our current understanding of treatment-induced oral mucositis, dental plaque, and caries formation and highlight the need for future research to examine the effect of RT/CRT on the sinonasal and oropharyngeal microbiome. In addition, future research should use larger cohorts, examine the impact of the microbiome on treatment response, and study the effect of manipulating the microbiome to overcome therapy resistance.

Azithromycin in high-risk, refractory chronic rhinosinusitus after endoscopic sinus surgery and corticosteroid irrigations: a double-blind, randomized, placebo-controlled trial

BACKGROUND

Refractory chronic rhinosinusitis (CRS) remains a significant burden for patients, often leaving them with few therapeutic options that provide low-morbidity, long-term, and meaningful symptomatologic and endoscopic disease improvement. Macrolides have long been thought to offer both an immunomodulatory and antimicrobial effect. Our objective was to evaluate the efficacy of low-dose, long-term azithromycin in a carefully selected high-risk population failing appropriate medical therapy of budesonide nasal irrigations (BNIs) and endoscopic sinus surgery (ESS).

METHODS

A double-blind, randomized, placebo-controlled trial was completed in a single tertiary-care center assessing the addition of 250 mg azithromycin, 3 times per week for 16 weeks, in adults failing ESS and high-volume BNIs. Associated comorbidities, as well as symptomatologic, microbiologic, and serologic values, were systematically collected.

RESULTS

A total of 128 patients were enrolled and underwent ESS followed by BNI. At the 4-month post-ESS visit, 48 patients showed disease persistence and were randomized to azithromycin or placebo. Overall, azithromycin, when compared with placebo, did not show a statistically significant difference in disease clearance (54% vs 33%, respectively; p = 0.146), although patients with disease clearance who were on azithromycin showed significantly better 22-item Sino-Nasal Outcome Test score improvements than patients on placebo (18 vs -0.9, respectively; p = 0.046). In a subgroup analysis excluding aspirin-exacerbated respiratory disease (AERD) patients, azithromycin significantly improved disease clearance when compared with placebo (71% vs 35%, respectively; p = 0.031), with a number needed to treat of 3 (2.8).

CONCLUSION

Low-dose azithromycin is a therapeutic option with few side effects. Its use can show favorable clinical outcomes in this difficult-to-treat population, especially if patients are AERD-negative.