INFLUENCE OF ALLERGY ON THE IMMUNOMODULATORY AND CLINICAL EFFECTS OF LONG-TERM LOW-DOSE MACROLIDE TREATMENT OF NASAL POLYPOSIS

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.

Immunomodulatory Effects of Macrolides Considering Evidence from Human and Veterinary Medicine

Macrolide antimicrobial agents have been in clinical use for more than 60 years in both human and veterinary medicine. The discovery of the non-antimicrobial properties of macrolides and the effect of immunomodulation of the inflammatory response has benefited patients with chronic airway diseases and impacted morbidity and mortality. This review examines the evidence of antimicrobial and non-antimicrobial properties of macrolides in human and veterinary medicine with a focus toward veterinary macrolides but including important and relevant evidence from the human literature. The complete story for these complex and important molecules is continuing to be written.

Pleiotropic effects of antibiotics on T cell metabolism and T cell-mediated immunity

T cells orchestrate adaptive and innate immune responses against pathogens and transformed cells. However, T cells are also the main adaptive effector cells that mediate allergic and autoimmune reactions. Within the last few years, it has become abundantly clear that activation, differentiation, effector function, and environmental adaptation of T cells is closely linked to their energy metabolism. Beyond the provision of energy equivalents, metabolic pathways in T cells generate building blocks required for clonal expansion. Furthermore, metabolic intermediates directly serve as a source for epigenetic gene regulation by histone and DNA modification mechanisms. To date, several antibiotics were demonstrated to modulate the metabolism of T cells especially by altering mitochondrial function. Here, we set out to systematically review current evidence about how beta-lactam antibiotics, macrolides, fluoroquinolones, tetracyclines, oxazolidinones, nitroimidazoles, and amphenicols alter the metabolism and effector functions of CD4+ T helper cell populations and CD8+ T cells in vitro and in vivo. Based on this evidence, we have developed an overview on how the use of these antibiotics may be beneficial or detrimental in T cell-mediated physiological and pathogenic immune responses, such as allergic and autoimmune diseases, by altering the metabolism of different T cell populations.

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.

[Efficacy of clarithromycin in the adjuvant treatment of chronic periodontitis: a Meta-analysis]

OBJECTIVE

To evaluate the clinical efficacy of clarithromycin (CLM) in the adjuvant treatment of chronic periodontitis systematically, obtain reasonable conclusions through evidence-based medicine, and provide guidance for clinical rational drug use.

METHODS

Literature about CLM in the adjuvant treatment of chronic periodontitis was searched in CNKI, VIP, Wanfang, Chinese Biomedical Literature Database, PubMed, ScienceDirect, and Embase databases from inception to February 2019 using a computer. Meta-analysis was performed on the homogeneous study using RevMan 5.3 software after two independent reviewers screened the literature, evaluated the quality of the study, extracted the data, and evaluated the risk of bias in the included studies.

RESULTS

Six randomized controlled trials were included in 316 subjects. The meta-analysis showed that compared with the scaling and root planning (SRP) group, the probing depth (PD) was reduced in patients with CLM and SRP [MD=-1.00, 95%CI (-1.55, -0.45), P=0.000 04]. Clinical attachment loss was obtained [MD=-0.03, 95%CI (0.43, 0.65), P<0.000 01], and the difference between the groups was statistically significant. The modified sulcus bleeding index (mSBI) was reduced [MD=-0.01, 95%CI (-0.14, 0.19), P=0.66]. No significant difference was observed between the groups, but the decrease in mSBI was more significant in CLM combined with SRP group.

CONCLUSIONS

CLM combined with subgingival SRP can achieve remarkable results in treating chronic periodontitist.

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.

The Immunomodulatory Effects of Macrolides-A Systematic Review of the Underlying Mechanisms

Background

The mechanisms underlying the non-antimicrobial immunomodulatory properties of macrolides are not well understood.

Objectives

To systematically review the evidence for the immunomodulatory properties of macrolides in humans and to describe the underlying mechanism and extent of their influence on the innate and adaptive immune system.

Methods

A systematic literature search was done in MEDLINE using the OVID interface from 1946 to December 2016 according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA). Original articles investigating the influence of four macrolides (azithromycin, clarithromycin, erythromycin, and roxithromycin) on immunological markers in humans were included.

Results

We identified 22 randomized, controlled trials, 16 prospective cohort studies, and 8 case–control studies investigating 47 different immunological markers (186 measurements) in 1,834 participants. The most frequently reported outcomes were a decrease in the number of neutrophils, and the concentrations of neutrophil elastase, interleukin (IL)-8, IL-6, IL-1beta, tumor necrosis factor (TNF)-alpha, eosinophilic cationic protein, and matrix metalloproteinase 9. Inhibition of neutrophil function was reported more frequently than eosinophil function. A decrease in T helper (Th) 2 cells cytokines (IL-4, IL-5, IL-6) was reported more frequently than a decrease in Th1 cytokines (IL-2, INF-gamma).

Conclusion

Macrolides influence a broad range of immunological mechanisms resulting in immunomodulatory effects. To optimize the treatment of chronic inflammatory diseases by macrolides, further studies are necessary, particularly comparing different macrolides and dose effect relationships.

Clarithromycin in the Management of Chronic Rhinosinusitis: Preliminary Results of a Possible Its New Use

The aim of this study is to evaluate the efficacy and safety of prolonged therapy with low-dose clarithromycin in patients with chronic rhinosinusitis with polyps (CRSwP) after endoscopic sinus surgery (ESS). A total of 10 patients with CRSwP were identified and subjected to bilateral ESS. In post-operative patients they were treated with nasal wash with saline solution and steroid sprays (beclomethasone). During follow-up, after 30-40 days after the operation (M = 35.4 SD = +4.33), patients reported a worsening of symptoms with onset of nasal obstruction; reduction/loss of smell; headache; onset of viscous secretions and therefore all patients continued therapy with saline nasal irrigation, topical steroid therapy and started macrolide (clarithromycin 500 mg/pill: 1 pill/day for 3 days a week for 1 month). 22-item SinoNasal Outcome Test (SNOT-22) and a score to the endoscopic evaluation (endoscopic appearance score, EAS) before and after treatment were performed to evaluate efficacy of treatment. The results of the SNOT-22 and EAS showed statistically significant improvements (p < 0.05) for some parameters such as: the need to blow nose, sneezing, hyposmia, viscous mucous secretions about the SNOT-22 and reduction of secretions and edema of the nasal mucosa about the EAS. The preliminary results of our study show that the low-dose clarithromycin for a period of 1 month can improve patient complaints with CRSwP not only through the antibacterial properties but also for the immunomodulatory characteristics.

Effects of Preoperative Clarithromycin Administration in Patients with Nasal Polyposis

OBJECTIVE

In recent years, various investigators have shown considerable interest in the use of macrolide antibiotics for treatment of chronic rhinosinusitis and nasal polyposis. The aim of this study was to evaluate the clinical effects of preoperative long-term, low-dose clarithromycin administration in patients with nasal polyposis.

METHODS

Eighty nasal polyp patients (42 non-atopic and 38 atopic) were included in this prospective, non-placebo controlled investigation and randomized equally to either the combined clarithromycin-surgical or surgical group. Forty patients received 500 mg of clarithromycin daily for eight weeks, and, after evaluation, they were treated by functional endoscopic sinus surgery (FESS). The other 40 patients were treated only surgically. The nasal symptom scores and endoscopic scores after macrolide treatment/surgical treatment, and after six and 12 months of follow-up were evaluated.

RESULTS

After clarithromycin therapy, we found improvement in symptom scores in 25/40, and improvement in endoscopic scores in 19/40 patients. We found no significant difference in nasal symptom score between allergic and non-allergic patients regarding the outcome to macrolide (p = 0.352) or surgical treatment (p = 0.396). When we compared differences between endoscopic scores at the time points of 12 months and six months postoperatively (ESt12 minus ESt6), we found statistically lower differences in the clarithromycin-surgery group than in the surgery group (p = 0.006).

CONCLUSION

Preoperative clarithromycin administration postponed nasal polyp relapse after FESS. Allergies have no influence on the clinical efficacy of clarithromycin therapy and on the efficacy of FESS.

Does systemic clarithromycin therapy have an inhibitory effect on tympanosclerosis? An experimental animal study

Objective:

To demonstrate the inhibitory effects of clarithromycin on in vitro tympanosclerosis.

Method:

Twenty-eight rats were divided into three groups: a clarithromycin group, a non-clarithromycin group and a negative control group. Those in the first two groups were injected with Streptococcus pneumoniae following a myringotomy, and tympanosclerosis was experimentally induced. Oral clarithromycin therapy was administered in the clarithromycin group. The other groups received no medical treatment.

Results:

All eardrums in the clarithromycin and non-clarithromycin groups developed myringosclerosis, but there was only one eardrum, in the clarithromycin group, with very severe myringosclerosis. In the clarithromycin group, 11 ears showed no inflammation and there were no ears with severe inflammation. In the non-clarithromycin group, there were 11 ears with severe inflammation. The mean eardrum thickness in the clarithromycin group was 20.93 µm and in the non-clarithromycin group it was 42.71 µm.

Conclusion:

Acute otitis media and myringotomies induced tympanosclerosis, but clarithromycin reduced the severity of tympanosclerosis.

High and low doses of clarithromycin treatment are associated with different clinical efficacies and immunomodulatory properties in chronic rhinosinusitis

BACKGROUND

Low-dose clarithromycin has been recommended for the treatment of chronic rhinosinusitis without nasal polyps. However, it is uncertain whether a high dose of clarithromycin is more effective than a low dose.

METHODS

Forty-three chronic rhinosinusitis patients were randomised to low-dose or high-dose clarithromycin groups, and clinical efficacy was evaluated. Pre- and post-treatment measures included: nasal symptom assessment, endoscopic inspection (Lund-Kennedy system), a quality of life questionnaire (the Sino-Nasal Outcome Test 20) and examination of cytokine levels (interleukin-5 and -8) in nasal secretions.

RESULTS

The high dose of clarithromycin was significantly better in terms of clinical efficacy than the low dose for the treatment of chronic rhinosinusitis (p < 0.025). Significant differences in nasal cytokine levels (interleukin-5 and -8) were also observed between the low-dose and high-dose groups after short-term clarithromycin treatment (p < 0.025).

CONCLUSION

Short-term, high-dose clarithromycin appears to be more effective for the treatment of chronic rhinosinusitis than low-dose clarithromycin.