A pilot study of low-dose erythromycin in bronchiectasis

The effect of azithromycin on sputum inflammatory markers in bronchiectasis

BACKGROUND

Long term macrolide treatment has been found beneficial in bronchiectasis (BE) -pathogical bronchial dilatation- possibly due to a combined anti-bacterial and immunomodulatory effect. The exact mechanism of inflammatory response is unknown. Here, we investigated the effect of maintenance macrolide treatment on the inflammatory response in BE. In addition, we assessed the inflammatory profile in BE in relation to disease severity.

METHODS

During the BAT randomized controlled trial (investigating the effect of 1 year of azithromycin (AZM) in 83 BE patients), data on BE severity, lung function and sputum microbiology was collected. For the current study, a wide range of inflammatory markers were analysed in 3- monthly sputum samples in all participants.

RESULTS

At baseline, marked neutrophilic but also eosinophilic inflammation was present in both groups, which remained stable throughout the study and was not affected by AZM treatment. Significant upregulation of pro-inflammatory markers correlated with FEV₁ < 50% (TNFα, ECP, IL-21, IL-1, p = 0.01- 0.05), H. influenzae (HI) colonization (MPO, ECP, MIP-1, TNFα, IL-21, Il-8, IL-1, IL-1α, p < 0.001 - 0.04) and number of exacerbations (MPO, ECP, VEGF, MMP-9, p = 0.003 - 0.01). Surprisingly, colonization with P. aeruginosa (PA) was found to correlate with an attenuated inflammatory response compared to non-PA colonized. In placebo-treated patients, presence of an infectious exacerbation was reflected by a significant excessive increase in inflammation as compared to a non-significant upregulation in the AZM-treated patients.

CONCLUSION

One year of AZM treatment did not result in attenuation of the inflammatory response in BE. Increasing disease severity and the presence of an exacerbation were reflected by upregulation of pro-inflammatory markers.

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.

Role of Erythromycin-Regulated Histone Deacetylase-2 in Benign Tracheal Stenosis

Objective

This study aims to explore the role of erythromycin-regulated histone deacetylase-2 in benign tracheal stenosis.

Methods

The rabbit model of tracheal stenosis was established. The rabbits were randomly divided into 8 groups. Histone deacetylase-2 (HDAC2) expression was detected by immunofluorescence. The expression of type I collagen and type III collagen was detected by immunohistochemical method. The expression of TGF-β1, VEGF and IL-8 in serum and alveolar lavage fluid was detected by ELISA. The expression of HDAC2, TGF-β1, VEGF and IL-8 in serum and alveolar lavage fluid was detected by ELISA. The expression of HDAC2, TGF-

Results

In Erythromycin (ERY) group, ERY + Budesonide group, ERY + Vorinostat group and ERY + Budesonide + Vorinostat group, the degree of bronchial stenosis was alleviated, and the mucosal epithelium was still slightly proliferated. The effect of ERY combined with other drugs was more obvious. The HDAC2 protein expression increased significantly in ERY group, ERY + Budesonide group and ERY + Budesonide + Vorinostat group and decreased significantly in Vorinostat group, the expression of collagen I and III decreased significantly in ERY group, ERY + Budesonide group and ERY + Budesonide + Vorinostat group (P < 0.05). The TGF-β1, VEGF and IL-8 in serum and alveolar lavage fluid was detected by ELISA. The expression of HDAC2, TGF-P < 0.05). The TGF-

Conclusions

Erythromycin inhibited inflammation and excessive proliferation of granulation tissue after tracheobronchial mucosal injury by up-regulating the expression of HDAC2, it promoted wound healing and alleviated tracheobronchial stenosis. When combined with budesonide, penicillin and other glucocorticoids and antibiotics, it had a good synergistic effect. However, vorinostat could attenuate erythromycin's effect by down-regulating the expression of HDAC2. It may have good clinical application prospects in the treatment of tracheal stenosis.

Successful treatment of three patients with organizing pneumonia associated with rheumatoid arthritis using clarithromycin and prednisolone

Macrolides have anti-inflammatory effects and have been used to treat diffuse panbronchiolitis, bronchiectasis, and cystic fibrosis. Lately, several cases of cryptogenic organizing pneumonia (COP) and radiotherapy-related organizing pneumonia (OP) that were successfully treated with macrolides considering their anti-inflammatory effects were reported. We report three cases of OP associated with rheumatoid arthritis (RA) successfully treated with clarithromycin (CAM) and prednisolone (PSL). Case 1: A 70-year-old woman suffering from RA was admitted with cough and severe dyspnea. She was diagnosed with OP associated with RA on the basis of computed tomography (CT) findings and transbronchial lung biopsy results. She was successfully treated with PSL and cyclosporine A. At the exacerbation of OP, she was successfully treated with CAM and PSL. Case 2: A 74-year-old man suffering from COP visited our department with arthralgia and articular swellings. He was diagnosed with RA, which was thought to be associated with OP. He was successfully treated with CAM and PSL. Case 3: A 54-year-old man suffering from RA presented with an exacerbation of arthralgia and articular swellings and cough. He was diagnosed with OP associated with RA on the basis of CT findings. He was successfully treated with CAM and PSL. The present cases suggest that CAM and PSL treatment may be effective in some cases of OP associated with RA.

The Spectrum of Non-asthmatic Airway Diseases Contributing to Cough in the Adult

PURPOSE OF REVIEW

Cough becomes a pathologic reflex when the airways are inflamed and overwhelmed with excessive mucus. The goal of this review is to discuss acute and chronic cough syndromes caused by non-asthmatic airway diseases.

RECENT FINDINGS

Acute cough syndrome is short-lived and self-limited. Acute bronchitis and diffuse acute infectious bronchiolitis (DAIB) are examples. The former is usually caused by a viral illness; the latter by Mycoplasma pneumoniae, influenza, and Haemophilus influenzae. Causes of chronic cough in the adult include chronic bronchitis, non-infectious bronchiolitis, and non-cystic fibrosis bronchiectasis.

SUMMARY

Supportive measures are recommended for acute bronchitis and antibiotic use is discouraged. Antibiotics may be needed for DAIB. Smoking cessation and bronchodilators can control cough in chronic bronchitis. Therapeutic approaches for non-infectious bronchiolitis depend on the varied etiology. The hallmark of bronchiectasis is a chronic infection of the airways, and antibiotics, mucus clearance measures, and bronchodilators are all supportive.

Meta-analysis of macrolide maintenance therapy for prevention of disease exacerbations in patients with noncystic fibrosis bronchiectasis

BACKGROUND

Macrolide maintenance treatment remains controversial for patients with noncystic fibrosis (non-CF) bronchiectasis, we performed a meta-analysis to estimate the benefits and safety of macrolides therapy in adults and children with non-CF bronchiectasis.

METHODS

PubMed, Embase, the Cochrane Library, and Web of Science databases were searched for all the randomized controlled trials of macrolides for treating non-CF bronchiectasis. The primary outcome was improvement of bronchiectasis exacerbations. Secondary outcomes included adverse events and macrolide resistance.

RESULTS

A total of 10 studies involving 602 patients were included in the analysis. Pooled results showed that macrolide therapy significantly reduced the number of patients who suffered from exacerbations (RR = 1.56, 95% CI = 1.14-2.14, P = .006, I = 72%), number of patients who experienced at least 3 exacerbations (RR = 0.55, 95% CI = 0.39-0.77, P = .0005, I = 40%), average exacerbations per patient during the observation time (SMD = -0.69, 95% CI = -1.06 to -0.32, P = .0002, I = 60%), and bronchiectasis exacerbation-related admissions (RR = 0.46, 95% CI = 0.23-0.96, P = .04, I = 0%). Specified subgroup analyses of the number of patients free from exacerbations were further performed; macrolide therapy showed a significant benefit in both children (RR 5.03, 95% CI 2.02-12.50, P = .0005, I = 45%) and adults (RR = 1.66, 95% CI = 1.37-2.02, P < .00001, I = 79%); azithromycin showed a significant reduction on the number of patients who suffered from exacerbations (RR = 2.25, 95% CI = 1.67-3.02, P < .00001, I = 0%), was different from erythromycin (RR = 1.33, 95% CI = 0.92-1.94, P = .13, I = 0%) and roxithromycin (RR = 1.14, 95% CI = 0.97-1.35, P = .11, I = 0%). The pooled results also showed no higher risk of adverse events (RR = 0.98, 95% CI = 0.85-1.13, P = .80, I = 8%), even a lower risk of severe adverse events (RR = 0.53, 95% CI = 0.33-0.85, P = .009, I = 0%). However, a higher risk of macrolide resistance (RR = 3.59, 95% CI 2.6-4.96, P < .00001, I = 0%) was observed.

CONCLUSION

For both children and adults with non-CF bronchiectasis, macrolide maintenance therapy can effectively reduce bronchiectasis exacerbations, especially for patients with more frequent exacerbations and needing hospital treatment. Azithromycin was more effective than other macrolides. Macrolide maintenance therapy did not increase the risk of adverse events, but may increase the risk of macrolide resistance.

Bronchiectasis: Treatment decisions for pulmonary exacerbations and their prevention

Interest in bronchiectasis has increased over the past two decades, as shown by the establishment of disease-specific registries in several countries, the publication of management guidelines and a growing number of clinical trials to address evidence gaps for treatment decisions. This review considers the evidence for defining and treating pulmonary exacerbations, the approaches for eradication of newly identified airway pathogens and the methods to prevent exacerbations through long-term treatments from a pragmatic practice-based perspective. Areas for future studies are also explored. Watch the video abstract.

Azithromycin or erythromycin? Macrolides for non-cystic fibrosis bronchiectasis in adults: A systematic review and adjusted indirect treatment comparison

Non-cystic fibrosis (non-CF) bronchiectasis is a condition characterized by an airway inflammatory response to bacterial pathogens. Frequent exacerbations have a major influence on the quality of life. Macrolide antibiotics have not only antibacterial but also immune-regulation effects. It is proved that macrolides have a benefit in preventing exacerbations. However, it is still uncertain whether azithromycin or erythromycin is more effective and safe. The purpose of this study was to answer the following question: Which kind of macrolide antibiotic is more effective and safe in preventing non-CF bronchiectasis exacerbation? We conducted a systematic review to identify randomized clinical trials published up to May 2017 that reported on macrolides for non-CF bronchiectasis and an adjusted indirect treatment comparison (AITC) between macrolides to evaluate their efficacy and safety. The direct comparison meta-analysis found that macrolides decreased the rate of exacerbation of non-CF bronchiectasis (risk ratio (RR) = 0.45; 95% confidence interval (CI) 0.36–0.55) with heterogeneity (I² = 63.7%, p = 0.064). The AITC showed that azithromycin had a significantly lower bronchiectasis exacerbation rate than erythromycin (RR = 0.35; 95% CI: 0.403–0.947). Azithromycin increased the risk of diarrhea and abnormal pain. This meta-analysis suggested that long-term treatment with macrolides significantly reduced the incidence of non-CF bronchiectasis exacerbation. Moreover, azithromycin is more efficient than roxithromycin and erythromycin in preventing exacerbation.

Diffuse panbronchiolitis research in MEDLINE (1969-2017): Report of a bibliometric analysis

BACKGROUND

Given the well documented and undesired impact of diffuse panbronchiolitis (DPB), there is a need to create a statistical inventory of research output on DPB. The aim of this study was to identify and analyze different trends in publication over time, with technological additions.

METHODS

Articles indexed in MEDLINE regarding DPB were retrieved using PubMed. Citation results were categorized by article type, year of publication, language, and country.

RESULTS

A total of 657 publications, published between 1969 and 2017 were retrieved from PubMed; the year with the highest number of articles published was 1992 (n = 32). Japan accounted for 68.34% (n = 449) publications, followed by the United States of America (USA; 6.70%, n = 44) and China (5.48%, n = 36). English (n = 401) was the most commonly used language in the publications, followed by Japanese (n = 223) and Chinese (n = 16). Articles were published in 218 different journals; The Japanese Journal of Thoracic Diseases published the maximum number of articles, accounting for 13.7% (n = 90) citations. Sugiyama Y was the most productive author and contributed to 12 publications.

CONCLUSIONS

This was the first bibliometric analysis of DPB. Between 1991 and 2000, the number of publications on DPB literature reached a peak, and although the frequency of publication has decreased recently, the quantity of DPB research during the past 48 years is adequate and satisfactory. Overall, the publications on DPB have undergone exponential growth over the last 30 years.

Macrolide antibiotics for bronchiectasis

BACKGROUND

Bronchiectasis is a chronic respiratory disease characterised by abnormal and irreversible dilatation and distortion of the smaller airways. Bacterial colonisation of the damaged airways leads to chronic cough and sputum production, often with breathlessness and further structural damage to the airways. Long-term macrolide antibiotic therapy may suppress bacterial infection and reduce inflammation, leading to fewer exacerbations, fewer symptoms, improved lung function, and improved quality of life. Further evidence is required on the efficacy of macrolides in terms of specific bacterial eradication and the extent of antibiotic resistance.

OBJECTIVES

To determine the impact of macrolide antibiotics in the treatment of adults and children with bronchiectasis.

SEARCH METHODS

We identified trials from the Cochrane Airways Trials Register, which contains studies identified through multiple electronic searches and handsearches of other sources. We also searched trial registries and reference lists of primary studies. We conducted all searches on 18 January 2018.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of at least four weeks' duration that compared macrolide antibiotics with placebo or no intervention for the long-term management of stable bronchiectasis in adults or children with a diagnosis of bronchiectasis by bronchography, plain film chest radiograph, or high-resolution computed tomography. We excluded studies in which participants had received continuous or high-dose antibiotics immediately before enrolment or before a diagnosis of cystic fibrosis, sarcoidosis, or allergic bronchopulmonary aspergillosis. Our primary outcomes were exacerbation, hospitalisation, and serious adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the titles and abstracts of 103 records. We independently screened the full text of 40 study reports and included 15 trials from 30 reports. Two review authors independently extracted outcome data and assessed risk of bias for each study. We analysed dichotomous data as odds ratios (ORs) and continuous data as mean differences (MDs) or standardised mean differences (SMDs). We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included 14 parallel-group RCTs and one cross-over RCT with interventions lasting from 8 weeks to 24 months. Of 11 adult studies with 690 participants, six used azithromycin, four roxithromycin, and one erythromycin. Four studies with 190 children used either azithromycin, clarithromycin, erythromycin, or roxithromycin.We included nine adult studies in our comparison between macrolides and placebo and two in our comparison with no intervention. We included one study with children in our comparison between macrolides and placebo and one in our comparison with no intervention.In adults, macrolides reduced exacerbation frequency to a greater extent than placebo (OR 0.34, 95% confidence interval (CI) 0.22 to 0.54; 341 participants; three studies; I2 = 65%; moderate-quality evidence). This translates to a number needed to treat for an additional beneficial outcome of 4 (95% CI 3 to 8). Data show no differences in exacerbation frequency between use of macrolides (OR 0.31, 95% CI 0.08 to 1.15; 43 participants; one study; moderate-quality evidence) and no intervention. Macrolides were also associated with a significantly better quality of life compared with placebo (MD -8.90, 95% CI -13.13 to -4.67; 68 participants; one study; moderate-quality evidence). We found no evidence of a reduction in hospitalisations (OR 0.56, 95% CI 0.19 to 1.62; 151 participants; two studies; I2 = 0%; low-quality evidence), in the number of participants with serious adverse events, including pneumonia, respiratory and non-respiratory infections, haemoptysis, and gastroenteritis (OR 0.49, 95% CI 0.20 to 1.23; 326 participants; three studies; I2 = 0%; low-quality evidence), or in the number experiencing adverse events (OR 0.83, 95% CI 0.51 to 1.35; 435 participants; five studies; I2 = 28%) in adults with macrolides compared with placebo.In children, there were no differences in exacerbation frequency (OR 0.40, 95% CI 0.11 to 1.41; 89 children; one study; low-quality evidence); hospitalisations (OR 0.28, 95% CI 0.07 to 1.11; 89 children; one study; low-quality evidence), serious adverse events, defined within the study as exacerbations of bronchiectasis or investigations related to bronchiectasis (OR 0.43, 95% CI 0.17 to 1.05; 89 children; one study; low-quality evidence), or adverse events (OR 0.78, 95% CI 0.33 to 1.83; 89 children; one study), in those receiving macrolides compared to placebo. The same study reported an increase in macrolide-resistant bacteria (OR 7.13, 95% CI 2.13 to 23.79; 89 children; one study), an increase in resistance to Streptococcus pneumoniae (OR 13.20, 95% CI 1.61 to 108.19; 89 children; one study), and an increase in resistance to Staphylococcus aureus (OR 4.16, 95% CI 1.06 to 16.32; 89 children; one study) with macrolides compared with placebo. Quality of life was not reported in the studies with children.

AUTHORS' CONCLUSIONS

Long-term macrolide therapy may reduce the frequency of exacerbations and improve quality of life, although supporting evidence is derived mainly from studies of azithromycin, rather than other macrolides, and predominantly among adults rather than children. However, macrolides should be used with caution, as limited data indicate an associated increase in microbial resistance. Macrolides are associated with increased risk of cardiovascular death and other serious adverse events in other populations, and available data cannot exclude a similar risk among patients with bronchiectasis.

Clarithromycin mitigates radiation pneumonitis in patients with lung cancer treated with stereotactic body radiotherapy

Background

Radiation pneumonitis is a critical pulmonary toxicity after irradiation of the lung. Macrolides including clarithromycin (CAM) are antibiotics. They also have immunomodulatory properties and are used to treat respiratory inflammatory diseases. Radiation pneumonitis has similar pathology to them. Adverse reactions to macrolides are few and self-limited. We thus administered CAM to patients with high-risk factors for radiation pneumonitis, and retrospectively investigated whether CAM mitigated radiation pneumonitis following stereotactic body radiotherapy (SBRT).

Methods

Among consecutive patients treated with SBRT, we retrospectively examined lung cancer patients treated with a total dose of 40-60 Gy in 5-10 fractions and followed ≥6 months. Since January 2014, CAM has been administered in patients with pretreatment predictable radiation pneumonitis high-risk factors, including idiopathic interstitial pneumonias (IIPs), and elevated Krebs von den Lungen-6 (KL-6) and/or surfactant protein D (SP-D), and in patients developing early onset radiation pneumonitis.

Results

Five hundred and eighty eligible patients were identified and divided into 445 patients during the non-CAM-administration era (non-CAM-era) (before December 2013) and 136 patients during the CAM-administration era (CAM-era) (after January 2014). Median follow-up durations were 38.0 and 13.9 months, respectively. The rates of radiation pneumonitis ≥ grade 2 and ≥ grade 3 were significantly lower in CAM-era (grade ≥2, 16% vs. 9.6%, P=0.047; grade ≥3, 3.8% vs. 0.73%, P=0.037). For patients with the pretreatment predictable high-risk factors, the rate of radiation pneumonitis ≥ grade 3 was significantly lower, and that of grade ≥2 had a lower tendency (grade ≥3, 7.2% vs. 0%, P=0.011; grade ≥2, 21% vs. 9.6%, P=0.061). For patients developing early onset radiation pneumonitis, the rate of radiation pneumonitis ≥ grade 3 was also significantly lower (23% vs. 0%, P<0.05). Multivariate analysis revealed that dose-volumetric factor, the pretreatment predictable high-risk factors and non-CAM-administration era were significantly associated with or trended toward radiation pneumonitis ≥ grade 2 and ≥ grade 3.

Conclusions

CAM mitigated radiation pneumonitis following SBRT. The efficacy of CAM should be confirmed in prospective studies.

Exacerbation of Bronchiectasis

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Cryptogenic organizing pneumonia-Results of treatment with clarithromycin versus corticosteroids-Observational study

Background

Cryptogenic organizing pneumonia (COP) is a clinicopathological syndrome of unknown origin. Corticosteroids are the standard treatment, but clarithromycin (CAM) is also effective. The aim of this observational retrospective study was to compare the results of CAM versus prednisone (PRE) treatment in patients with biopsy-proven OP without respiratory insufficiency.

Material and methods

In a 15-year period, 40 patients were treated with CAM (500 mg twice daily orally for 3 months) and 22 with PRE (mean initial dose of 0.67 ± 0.24 mg/kg/d for a mean of 8.59 ± 3.05 months).

Results

The clinical presentation, laboratory, and radiological findings did not differ markedly between patients treated with CAM and PRE, with the exception of a higher frequency of sweats (55% vs. 23%; p < 0.015), ground glass opacities (95% vs. 50%; p <0.0001) and nodular lesions (45% vs. 18%; p = 0.036) in the CAM group. A complete response was achieved in 35(88%) patients treated with CAM and in all treated with PRE. Patients treated with PRE relapsed more frequently than those treated with CAM (54.5% vs. 10%; p < 0.0001). Corticosteroid-related adverse events were noticed in 8(6.5%) patients (with one death), but CAM caused only one (2.5%) allergic reaction. A FVC >80% identified patients who might be successfully treated with CAM with a sensitivity of 60% and a specificity of 88.57% (AUC 0.869; 95% CI 0.684–1; p = 0.008); the figures for the FEV1 were >70%, a sensitivity of 60%, and a specificity of 91.43% (AUC 0.809; 95%CI 0.609–1; p = 0.027).

Conclusions

CAM can be used to treat COP patients in whom the pulmonary function parameters are within normal limits. Such therapy is shorter, better tolerated, and associated with fewer adverse events and relapses than is PRE. However, the therapy is ineffective in some patients.

Immunity status of invasive pulmonary aspergillosis patients with structural lung diseases in Chinese adults

BACKGROUND

Invasive pulmonary aspergillosis (IPA) is a fungal infection frequently observed in patients with immune dysfunction, such as those suffering from structural lung diseases. Nevertheless, studies assessing IPA combined with other common respiratory diseases remain scarce, particularly those regarding the immune status of its patients. Different structural lung diseases are known to differently affect patient immune status; however, the mechanisms by which this is conferred have yet to be determined. Thus, our study aims to compare the immune status of IPA patients with the structural lung diseases chronic obstructive pulmonary diseases (COPD), interstitial lung disease (ILD) and non-cystic fibrosis bronchiectasis (NCFB).

METHODS

This study was performed retrospectively with data collected over the years 2004 to 2013 at Shanghai Pulmonary Hospital, Tongji University, and included 77 patients whose lower respiratory tract (LRT) samples tested positive for. Our analysis considered blood examinations of CD3+, CD4+, CD8+, CD4+/CD8+, IgG, IgA and IgM levels.

RESULTS

CD4+/CD8+ double positive cells, representing cell-mediated immunity, were less abundant in IPA patients with COPD than those with ILD and NCFB (0.81±0.09 vs. 1.39±0.25 and 0.81±0.09 vs. 1.57±0.06, respectively, P<0.001). In agreement with this result, corticosteroid and broad-spectrum antibiotic use were most common in individuals with COPD (57%). IgA levels, which indicate humoral immunity, were lower in IPA patients with NCFB than those with COPD or ILD (0.95±0.28 vs. 1.64±0.40 g/L and 0.95±0.28 vs. 3.16±0.83 g/L, respectively, P<0.001).

CONCLUSIONS

Immunity status differs between IPA patients with different structural lung diseases. Among IPA patients with COPD, ILD and NCFB, those with COPD have the lowest cell-mediated immunity, while those with NCFB have the lowest humoral immunity.

Distribution of Major Pathogens from Sputum and Bronchoalveolar Lavage Fluid in Patients with Noncystic Fibrosis Bronchiectasis: A Systematic Review

Objective:

Noncystic fibrosis (non-CF) bronchiectasis remains as a common health problem in Asia. Pathogens’ distribution in airways of patients with non-CF bronchiectasis is important for doctors to make right decision.

Data Sources:

We performed this systematic review on the English language literatures from 1966 to July 2014, using various search terms included “pathogens” or “bacteria” or “microbiology” and “bronchiectasis” or “non-cystic fibrosis bronchiectasis” or “non-CF bronchiectasis” or “NCFB.”

Study Selection:

We included studies of patients with the confirmed non-CF bronchiectasis for which culture methods were required to sputum or bronchoalveolar lavage fluid (BALF). Weighted mean isolation rates for Haemophilus influenzae, Pseudomonas aeruginosa, Streptococcus pneumoniae, Stapylococcus aureus, Moxarella catarrhails were compared according to different methodology.

Results:

The total mean bacterial culture positive rates were 63%. For studies using sputum samples, the mean positive culture rates were 74%. For studies using BALF alone or BALF and sputum, it was 48%. The distributions of main bacterial strains were 29% for H. influenzae, 28% for P. aeruginosa, 11% for S. pneumoniae, 12% for S. aureus, and 8% for M. catarrhails with methodology of sputum. Meanwhile, the bacterial distributions were 37% for H. influenzae, 8% for P. aeruginosa, 14% for S. pneumoniae, 5% for S. aureus, and 10% for M. catarrhails with methodology of BALF alone or BALF and sputum. Analysis of the effect of different methodology on the isolation rates revealed some statistically significant differences.

Conclusions:

H. influenzae accounted for the highest percentage in different methodology. Our results suggested that the total positive culture rates and the proportion of P. aeruginosa from sputum and BALF specimens had significant differences, which can be used in further appropriate recommendations for the treatment of non-CF bronchiectasis.

Antibiotic therapy for stable non-CF bronchiectasis in adults - A systematic review

To provide an update on efficacy and safety of antibiotic treatments for stable non-cystic fibrosis (CF) bronchiectasis (BE). Systematic review based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines was done. Twenty-six studies (1.898 patients) fulfilled the inclusion criteria. Studies of inhaled tobramycin have revealed conflicting results regarding quality of life (QoL), exacerbations and admissions, but may result in sputum cultures negative for Pseudomonas aeruginosa, whereas studies investigating the effect of inhaled gentamycin have shown positive effects on sputum bacterial density, decrease in sputum cultures positive for P. aeruginosa, QoL and exacerbation rate, but no improvement in forced expiratory volume in first second (FEV₁). Oral azithromycin can reduce exacerbations, together with minor improvements in QoL and FEV₁. Furthermore, oral erythromycin reduces exacerbations, but has no effect on lung function, symptoms or QoL. Inhaled ciprofloxacin may reduce P. aeruginosa in sputum cultures, but without changes in lung function, exacerbations or QoL. Although with limited evidence, inhaled colistin may have effects on P. aeruginosa density, exacerbations and QoL, whereas studies on aztreonam revealed no significant clinical improvements in the outcomes of interest, including exacerbation rate. Adverse events, including bronchospasm, have been reported in association with tobramycin and aztreonam. Several antibiotic treatment regimens have been shown to improve QoL and exacerbation rate, whereas findings regarding sputum production, lung function and admissions have been conflicting. Evidence-based treatment algorithms for antibiotic treatment of stable non-CF BE will have to await large-scale, long-term controlled studies.

Respiratory manifestations and management in children with Common Variable Immunodeficiency

Common variable immunodeficiency is an antibody deficiency that usually presents in childhood with recurrent sino-pulmonary infections. Diagnostic delay is frequent and thus respiratory morbidity is common, ranging from recurrent suppurative bronchitis to bronchiectasis. Immunoglobulin replacement therapy is the mainstay of treatment, whilst prophylactic antibiotic therapy and muco-ciliary clearance are additional treatment options. This review examines the diagnosis and management of respiratory issues in children with CVID.

Prolonged antibiotics for non-cystic fibrosis bronchiectasis in children and adults

BACKGROUND

The vicious cycle hypothesis for bronchiectasis predicts that bacterial colonisation of the respiratory tract perpetuates inflammatory change. This damages the mucociliary escalator, preventing bacterial clearance and allowing persistence of pro-inflammatory mediators. Conventional treatment with physiotherapy and intermittent antibiotics is believed to improve the condition of people with bronchiectasis, although no conclusive data show that these interventions influence the natural history of the condition. Various strategies have been tried to interrupt this cycle of infection and inflammation, including prolonging antibiotic treatment with the goal of allowing the airway mucosa to heal.

OBJECTIVES

To determine the benefits of prolonged antibiotic therapy in the treatment of patients with bronchiectasis.

SEARCH METHODS

We searched the Cochrane Airways Group Trials Register and reference lists of identified articles. Searches were current as of February 2014.

SELECTION CRITERIA

Randomised trials examining the use of prolonged antibiotic therapy (for four or more weeks) in the treatment of bronchiectasis compared with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors to ask for missing information.

MAIN RESULTS

Eighteen trials met the inclusion criteria, randomly assigning a total of 1157 participants. Antibiotics were given for between four weeks and 83 weeks. Limited meta-analysis was possible because of the diversity of outcomes reported in these trials. Based on the number of participants with at least one exacerbation, the meta-analysis showed significant effects in favour of the intervention (odds ratio (OR) 0.31, 95% confidence interval (CI) 0.19 to 0.52; P value < 0.00001), with events occurring in 271 per 1000 people in the intervention arm (95% CI 126 to 385) and in 546 per 1000 in the control population, based on evidence of moderate quality. A non-statistically significant reduction in hospitalisation favoured the use of prolonged antibiotics with a moderate quality grade of supporting evidence (37 per 1000 in the intervention arm (95% CI 13 to 96) and 87 per 1000 in control (OR 0.40, 95% CI 0.14 to 1.11; P value = 0.08). Drug resistance developed in 36 of 220 participants taking antibiotics compared with 10 of 211 participants given placebo or standard therapy (OR 3.48, 95% CI 1.20 to 10.07; P value = 0.02), translating to natural frequencies of 155 per 1000 in the intervention arm (95% CI 59 to 346) and 50 per 1000 in the control arm. The intervention was well tolerated with no overall significant difference in withdrawal between treatment and placebo groups (OR 0.91, 95% CI 0.56 to 1.49). Diarrhoea was commonly reported as an adverse event, particularly with an oral intervention.

AUTHORS' CONCLUSIONS

Available evidence shows benefit associated with use of prolonged antibiotics in the treatment of patients with bronchiectasis, at least halving the odds of exacerbation (with 275 fewer exacerbations per every 1000 people treated in the antibiotic arm compared with the control arm) and hospitalisation (50 fewer hospitalisations per 1000 people in the antibiotic arm compared with the control arm). However, the risk of emerging drug resistance is increased more than threefold. This review is limited by diversity of trials and by evidence of moderate to low quality. Further randomised controlled trials with adequate power and standardised end points are required.

Effects of long-term use of macrolides in patients with non-cystic fibrosis bronchiectasis: a meta-analysis of randomized controlled trials

Background

The purpose of this study was to evaluate the clinical benefits and safety of the long-term use of macrolides in patients with non-cystic fibrosis (non-CF) bronchiectasis.

Methods

Embase, Pubmed, the Cochrane Library and Web of Science databases were searched from inception up to March 2014. The primary outcome was the improvement of exacerbations of bronchiectasis. Secondary endpoints included changes of microbiology, lung function, quality of life, sputum volume, adverse events and macrolide resistance.

Results

The literature search yielded 139 studies, ten of which containing 601 patients were included in this meta-analysis. Macrolides showed a statistically-significant improvement in reducing acute exacerbations per patient during follow-up treatment (RR = 0.55, 95% CI: 0.47, 0.64, P < 0.001), increasing the number of patients free from exacerbations (OR = 2.81, 95% CI: 1.85, 4.26, P < 0.001), and prolonging time to a first exacerbation (HR = 0.38, 95% CI: 0.28, 0.53, P < 0.001). Macrolides maintenance treatment was superior to control with respect to attenuating FEV1 decline (p = 0.02), improving sputum volume (p = 0.009) and SGRQ total scores (p = 0.02), but showed a higher risk of adverse events, especially diarrhea (OR = 5.36; 95% CI: 2.06, 13.98, P = 0.0006). Eradication of pathogens was improved in the macrolide group (OR = 1.76, 95% CI: 0.91, 3.41, P = 0.09), while pathogen resistance caused by macrolides dramatically increased (OR = 16.83, 95% CI: 7.26, 38.99, P < 0.001). The new appearance of a microbiologic profile or participant withdrawal due to adverse events showed no significant differences between the two groups.

Conclusion

In patients with non-CF bronchiectasis, macrolide maintenance treatment can effectively reduce frequency of exacerbations, attenuate lung function decline, decrease sputum volume, improve quality of life, but may be accompanied with increased adverse events (especially diarrhea) and pathogen resistance.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-0872-5) contains supplementary material, which is available to authorized users.

Non-anti-infective effects of antimicrobials and their clinical applications: a review

Antimicrobial agents are undoubtedly one of the key advances in the history of modern medicine and infectious diseases, improving the clinical outcomes of infection owing to their inhibitory effects on microbial growth. However, many antimicrobial agents also have biological activities stemming from their interactions with host receptors and effects on host inflammatory responses and other human or bacterial cellular biological pathways. These result in clinical uses of antimicrobial drugs that are distinct from their direct bacteriostatic or bactericidal properties. We reviewed the published literature regarding non-anti-infective therapeutic properties and proposed clinical applications of selected antimicrobials, specifically, macrolides, tetracyclines, sulfonamides, and ketoconazole. The clinical applications reviewed were varied, and we focused on uses that were clinically relevant (in terms of importance and burden of disease) and where published evidence exists. Such uses include chronic inflammatory pulmonary and skin disorders, chronic periodontitis, gastrointestinal dysmotility, rheumatoid arthritis, and cancer. Most of these potential therapeutic uses are not Food and Drug Administration approved. Clinicians need to weigh the use of antimicrobial agents for their non-anti-infective benefits, considering potential adverse effects and long-term effect on microbial resistance.

Poor survival in rheumatoid arthritis associated with bronchiectasis: a family-based cohort study

Background

Diffuse bronchiectasis (DB) may occur in rheumatoid arthritis (RA). CFTR (cystic fibrosis transmembrane conductance regulator) mutations predispose RA patients to DB, but the prognosis of RA-associated DB (RA-DB) is unclear.

Methods

We report long-term mortality data from a nationwide family-based association study of patients with RA only, DB only or RA-DB. We assessed mortality as a function of clinical characteristics and CF/CFTR-RD (CFTR-related disorders) mutations in 137 subjects from 24 kindreds. Potential risk factors were investigated by Cox proportional-hazard analysis with shared Gaussian random effects to account for within-family correlations.

Results

During a median follow-up of 11 years after inclusion, 18 patients died, mostly from cardiorespiratory causes. Survival was significantly lower for RA-DB patients than for unaffected relatives and for patients with RA or DB only. RA patients with DB had also a poorer prognosis in terms of survival after RA diagnosis (HR, 8.6; 95% CI, 1.5–48.2; P = 0.014) and from birth (HR, 9.6; 95% CI, 1.1–81.7; P = 0.039). Early onset of DB (HR, 15.4; 95% CI, 2.1–113.2; P = 0.007) and CF/CFTR-RD mutation (HR, 7.2; 95% CI, 1.4–37.1; P = 0.018) were associated with poorer survival in patients with RA-DB. Thus, CF/CFTR-RD mutations in RA patients with early-onset DB defined a subgroup of high-risk patients with higher mortality rates (log-rank test P = 1.28×10⁻⁵).

Conclusion

DB is associated with poorer survival in patients with RA. Early-onset DB and CFTR mutations are two markers that identify RA patients at a high risk of death, for whom future therapeutic interventions should be designed and evaluated.

Macrolide use leads to clinical and radiological improvement in patients with cryptogenic organizing pneumonia

Cryptogenic organizing pneumonia is an idiopathic form of organizing pneumonia (also known as bronchiolitis obliterans organizing pneumonia). Because cryptogenic organizing pneumonia is considered an inflammatory disease, it characteristically responds to the broad-spectrum antiinflammatory corticosteroids, although relapse is common on discontinued use. Additionally, long-term use of corticosteroids has many side effects. In severe cases in which corticosteroids have failed, either cytotoxic therapy or macrolide therapy is used. Because of the toxicity and adverse effects of cytotoxic therapy (e.g., cyclophosphamide), this therapy option cannot be used long term in refractory cases. Macrolide therapy has been shown to be an effective antiinflammatory agent that is relatively safe when used on a long-term basis in patients with cryptogenic organizing pneumonia.

Macrolide antibiotics for treatment of asthma in adults: a meta-analysis of 18 randomized controlled clinical studies

Mounting studies have been showed that long-term macrolides used in patients with asthma could improve the lung function and symptoms. However, a large number of studies have reported inconclusive results. The aim of this meta-analysis was to investigate the effect of macrolide antibiotics in patients with asthma. We have performed a search in PubMed, Embase, China National Knowledge Internet (CNKI), and Wanfang databases. The weighed mean difference (WMD) or standardized mean difference (SMD) was used to evaluate the pooled effect. Statistical analysis was performed by STATA 11.0 software. Totally 1306 patients were included in the meta-analysis. The overall results indicated that statistically significance of long-term macrolides therapy in patients with asthma on forced expiratory volume in 1 s (FEV1) (WMD: 0.11, P < 0.01), peak expiratory flow (PEF) (SMD: 0.25, P = 0.001), airway hyper-responsiveness (AHR) (SMD: 0.90, P = 0.04), forced vital capacity (FVC) (WMD: 0.18, P = 0.05) and FEV1/FVC (WMD: 1.93, P < 0.001), but no statistically significance on FEV1/predict, FVC/predict, symptom scores, quality of life scores (QOL), reliever inhaler puffs per 24 h, and cell counts in sputum and blood. The subgroup analysis indicated macrolides could increase FEV1 and PEF in Caucasian and Asian, decrease AHR in Caucasian, while cells counts of sputum improvement among Asian. Therefore, the study suggested that long-term marolides therapy in asthma may improved the FEV1, PEF, AHR, FVC, FEV1/FVC and cells counts in sputum, but it can't improve other lung function (FEV1/predict and FVC/predict) and clinical outcomes (such as symptom, quality of life etc.).

Long-term macrolide maintenance therapy in non-CF bronchiectasis: evidence and questions

Macrolide antibiotics have anti-inflammatory and immunomodulatory properties in addition to antibacterial activity. Until recently, only a small number of studies evaluating macrolides in patients with non-cystic fibrosis (CF) bronchiectasis had been published. These were open-label, uncontrolled, short-duration studies that included small numbers of patients. However, these studies suggested that macrolides can reduce exacerbation frequency, reduce sputum volume, and improve lung function in patients with non-CF bronchiectasis. Three recently published randomised, double-blind, placebo-controlled studies showed that macrolides (azithromycin or erythromycin) taken for between 6 and 12 months led to significant reductions in exacerbation rate and reduced the decline in lung function. In all studies, macrolides were generally well tolerated. The advantages of macrolide maintenance therapy need to be balanced against the risks, which include emergence of bacterial resistance, cardiotoxicity and ototoxicity. In addition, a key need is the consistent definition of endpoints for studies in non-CF bronchiectasis, particularly the definition of exacerbation, to allow systematic data analysis. Existing studies on the use of low-dose macrolides in non-CF bronchiectasis are encouraging, but further studies are needed to define the optimal agent, dose, duration for treatment, and the patients likely to benefit and long-term safety.

Antimicrobial treatment of non-cystic fibrosis bronchiectasis

Bronchiectasis unrelated to cystic fibrosis is characterized by chronic wet or productive cough, recurrent exacerbations and irreversible bronchial dilatation. After antibiotics and vaccines became available and living standards in affluent countries improved, its resulting reduced prevalence meant bronchiectasis was considered an 'orphan disease'. This perception has changed recently with increasing use of CT scans to diagnose bronchiectasis, including in those with severe chronic obstructive pulmonary disease or 'difficult to control' asthma, and adds to its already known importance in non-affluent countries and disadvantaged Indigenous communities. Following years of neglect, there is renewed interest in identifying the pathogenetic mechanisms of bronchiectasis, including the role of infection, and conducting clinical trials. This is providing much needed evidence to guide antimicrobial therapy, which has relied previously upon extrapolating treatments used in cystic fibrosis and chronic obstructive pulmonary disease. While many knowledge gaps and management challenges remain, the future is improving for patients with bronchiectasis.

Advantages and drawbacks of long-term macrolide use in the treatment of non-cystic fibrosis bronchiectasis

Non-cystic fibrosis (non-CF) bronchiectasis is a respiratory disease characterized by persistent airway inflammation and dilation of bronchial wall driven by various causes. Patients with bronchiectasis suffer from excessive sputum production, recurrent exacerbations, and progressive airway destruction. Major therapy for bronchiectasis is focused on breaking the "vicious cycle" of mucus stasis, infection, inflammation, and airway destruction. Growing evidences have been shown that macrolides possess immunoregulatory and anti-inflammatory functions beyond their antimicrobial effects. Macrolide antibiotics have been effectively used in the treatment of diffuse panbronchiolitis, CF and bronchiolitis obliterans syndrome. Currently a number of clinical trials were performed to assess macrolide treatment in the management of non-CF bronchiectasis. The purpose of this paper is to review the efficacy and potential risks of these recent studies on the use of macrolides in non-CF bronchiectasis.

Macrolide therapy in adults and children with non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis

Background

A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of macrolide therapy in adults and children with bronchiectasis.

Methods

We searched the PUBMED, EMBASE, CENTRAL databases to identify relevant studies. Two reviewers evaluated the studies and extracted data independently. The primary outcome was the number of bronchiectasis exacerbations. Secondary outcomes included exacerbation-related admissions, quality of life (QoL), spirometry, 6-minute walk test (6MWT) and adverse events.

Results

Nine eligible trials with 559 participants were included. Six were conducted on adults, and the remaining on children. Macrolide therapy significantly reduced the number of patients experiencing one or more exacerbation in adults [risk ratio (RR) = 0.59; 95% CI, 0.40 to 0.86; P = 0.006; I² = 65%] and children [RR = 0.86; 95% CI, 0.75–0.99; P = 0.04; I² = 0%], but not the number of patients with admissions for exacerbation. Macrolide therapy was also associated with reduced frequency of exacerbations in adults (RR = 0.42; 95% CI, 0.29 to 0.61; P<0.001; I² = 64%) and children (RR = 0.50; 95% CI, 0.35 to 0.71; P<0.001). Pooled analyses suggested that spirometry, including FEV₁ and FVC, were significantly improved in adults but not in children. Macrolide therapy improved the QoL (WMD, −6.56; 95% CI, −11.99 to −1.12; P = 0.02; I² = 86%) but no significant difference in 6MWT (WMD, 4.15; 95% CI, −11.83 to 20.13; P = 0.61; I² = 31%) and the overall adverse events (RR, 0.96; 95% CI, 0.82 to 1.13; P = 0.66; I² = 0%) in adults. However, reports of diarrhea and abdominal discomforts were higher with macrolide therapy.

Conclusions

Macrolide maintenance therapy, both in adults and children, was effective and safe in reducing bronchiectasis exacerbations, but not the admissions for exacerbations. In addition, macrolide administration in adults was associated with improvement in QoL and spirometry, but not 6WMT. Future studies are warranted to verify the optimal populations and clarify its potential effects on antimicrobial resistance.

[Why use long-term macrolide therapy in pediatric pulmonology?]

Macrolides are well-known antibiotics exerting antimicrobial as well as anti-inflammatory and immunomodulatory effects. Since the observation of a dramatic improvement in lung disease and survival in patients with diffuse panbronchiolitis, macrolides have been used over the long term in several chronic respiratory diseases. This review describes the results of trials that have evaluated long-term macrolides in the treatment of cystic fibrosis, non-cystic fibrosis bronchiectasis, and asthma, particularly focusing on the impact on children. It also provides new insights on the potential effects of macrolides on diffuse parenchymal lung diseases.

Bronchiectasis in older patients with chronic obstructive pulmonary disease : prevalence, diagnosis and therapeutic management

The prevalence of chronic obstructive pulmonary disease (COPD) increases with age. Recent evidence suggests that the finding of co-existent bronchiectasis is becoming increasingly common, possibly because of increased use of high-resolution CT scanning in the assessment of patients with COPD. This may represent a distinct phenotype of COPD, but, nevertheless, it is likely to pose an increased burden to health services and challenges in determining the correct management of these patients. Here, we review the factors associated with bronchiectasis in older patients with COPD and the evidence for many of the therapies currently used in the treatment of patients, providing a rational approach to their management.

Bronchiectasis: an update on current pharmacotherapy and future perspectives

INTRODUCTION

Bronchiectasis is a common condition and is likely to be underestimated, as bronchiectasis is now a recognised problem complicating other chronic lung diseases such as severe asthma, severe chronic obstructive pulmonary disease and advanced pulmonary fibrosis. In more advanced bronchiectasis, there is a vicious cycle of excess neutrophilic airways inflammation and chronic infection of the airways. This leads to the clinical syndrome, including a chronic productive cough and recurrent chest infections.

AREAS COVERED

This review provides an overview of the current pharmacotherapy options available and the potential future perspectives for treatment in adult patients with idiopathic or post-infection bronchiectasis. A PUBMED search for all Phase III and above trials on current therapies focusing on optimising airway dilatation and treatments to break the vicious cycle of infection and inflammation were sought. These therapies include antibiotics, anti-inflammatory and mucoactive therapies alongside chest physiotherapy. Landmark Phase II studies were also included.

EXPERT OPINION

Current practice has predominantly been based on treatment advised from national guidelines that are mainly grade D expert opinion. Randomised controlled trials are greatly needed to improve practice of evidence-based medicine.

Effectiveness and safety of macrolides in bronchiectasis patients: a meta-analysis and systematic review

PURPOSE

Macrolides has been studied as a potential therapeutic anti-inflammatory agent for bronchiectasis patients, which has used as an immunoregulation agent. However, the efficacy and safety results of macrolides across available randomized controlled trials (RCTs) are controversial. The aim of this systematic review is to evaluate the efficacy and safety of macrolides in bronchiectasis.

METHODS

RCTs of macrolides treatment for the patients of bronchiectasis published in PubMed and Cochrane Library were searched. Two authors independently extracted data and assessment the methodological quality. The primary efficacy outcome was the impact on the number of pulmonary exacerbation. Safety outcomes included adverse events and mortality.

RESULTS

Seven RCTs were found in the systematic review and six studies were included in the present meta-analysis. Macrolides treatment showed a significant reduced rate of pulmonary exacerbation (RR = 0.55, 95%CI = 0.43-0.70) compared with control groups. However, subgroup analysis failed to find any significant changes in total 46 patients (RR = 0.20, 95%CI = 0.03-1.58) for treatment not more than 3 months. The incidence rates of total adverse events showed no significant difference among the macrolides group and control groups.

CONCLUSIONS

Long-term treatment of bronchiectasis with macrolides can reduce incidence of pulmonary exacerbation, especially in the subgroup treatment 6 months or more. There was no evidence of increased adverse events with macrolides. However, to verify the best macrolides regimen, more studies based on larger sample size and stratified by ethnicity are still needed.

CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE

Erythromycin (PubChem CID 12560); Azithromycin (PubChem CID: 447043); Clarithromycin (PubChem CID: 84029); Roxithromycin (PubChem CID: 5480431).

New advances in the therapy of non-cystic fibrosis bronchiectasis

Non-cystic fibrosis bronchiectasis remains a common and important respiratory disease to date. It is a chronic pathology and consequently the patients usually require continuous treatment. In recent decades therapies that do not have scientific evidence of their benefits have been commonly used in non-cystic fibrosis bronchiectasis. Cystic fibrosis has provided the experience to extrapolate therapeutic approaches to other bronchiectasis patients. Finally, in the last few years some trials have been carried out specifically in non-cystic fibrosis bronchiectasis which aim to assess the efficacy of some of the treatments which are commonly used but sometimes without clear indication. This review will discuss the recent results from these trials, namely mucoactive, anti-inflammatory and antibiotic therapy. Several trials are ongoing and we hope they will be able to add clarification to the management of these patients.

Long-term macrolide treatment of chronic inflammatory airway diseases: risks, benefits and future developments

Macrolide antibiotics were discovered over 50 years ago and following their use as antimicrobials it became apparent that this group of antibiotics also possessed anti-inflammatory properties. Subsequent clinical trials showed benefits of macrolides as long-term adjuncts in the treatment of a spectrum of chronic inflammatory respiratory diseases, particularly diffuse panbronchiolitis, cystic fibrosis, post-transplant bronchiolitis obliterans and more recently chronic obstructive pulmonary disease (COPD). The evidence for efficacy of macrolides in the long-term treatment of chronic asthma and bronchiectasis is less well established. The mechanism(s) of action of macrolides in the treatment of these diseases remains unexplained, but may be due to their antibacterial and/or anti-inflammatory actions, which include reductions in interleukin-8 production, neutrophil migration and/or function. Macrolides have additional potentially beneficial properties including anti-viral actions and an ability to restore corticosteroid sensitivity. The increased prescribing of macrolides for long-term treatment could result in the development of microbial resistance and adverse drug effects. New macrolides have been developed which do not possess any antimicrobial activity and hence lack the ability to produce microbial resistance, but which still retain immunomodulatory effects. Potentially novel macrolides may overcome a significant barrier to the use of this type of drug for the long-term treatment of chronic inflammatory airway diseases.

Mechanisms of immune dysfunction and bacterial persistence in non-cystic fibrosis bronchiectasis

Bronchiectasis is a chronic inflammatory lung disease. The underlying cause is not identified in the majority of patients, but bronchiectasis is associated with a number of severe infections, immunodeficiencies and autoimmune disorders. Regardless of the underlying cause, the disease is characterised by a vicious cycle of bacterial colonisation, airway inflammation and airway structural damage. Inflammation in bronchiectasis is predominantly neutrophil driven. Neutrophils migrate to the airway under the action of pro-inflammatory cytokines such as interleukin-8, tumour necrosis factor-α and interleukin-1β, all of which are increased in the airway of patients with bronchiectasis. Bacterial infection persists in the airway despite large numbers of neutrophils that would be expected to phagocytose and kill pathogens under normal circumstances. Evidence suggests that neutrophils are disabled by multiple mechanisms including cleavage of phagocytic receptors by neutrophil elastase and inhibition of phagocytosis by neutrophil peptides. Complement activation is impaired and neutrophil elastase may cleave activated complement from pathogens preventing effective opsonisation. Organisms also evade clearance by adapting to chronic infection. The formation of biofilms, reduced motility and the down-regulation of virulence factors are among the strategies used to subvert innate immune mechanisms. Greater understanding of the mechanisms underlying chronic colonisation in bronchiectasis will assist in the development of new treatments for this important disease.

Azithromycin for prevention of exacerbations in non-cystic fibrosis bronchiectasis (EMBRACE): a randomised, double-blind, placebo-controlled trial

BACKGROUND

Azithromycin is a macrolide antibiotic with anti-inflammatory and immunomodulatory properties. We tested the hypothesis that azithromycin would decrease the frequency of exacerbations, increase lung function, and improve health-related quality of life in patients with non-cystic fibrosis bronchiectasis.

METHODS

We undertook a randomised, double-blind, placebo-controlled trial at three centres in New Zealand. Between Feb 12, 2008, and Oct 15, 2009, we enrolled patients who were 18 years or older, had had at least one pulmonary exacerbation requiring antibiotic treatment in the past year, and had a diagnosis of bronchiectasis defined by high-resolution CT scan. We randomly assigned patients to receive 500 mg azithromycin or placebo three times a week for 6 months in a 1:1 ratio, with a permuted block size of six and sequential assignment stratified by centre. Participants, research assistants, and investigators were masked to treatment allocation. The coprimary endpoints were rate of event-based exacerbations in the 6-month treatment period, change in forced expiratory volume in 1 s (FEV(1)) before bronchodilation, and change in total score on St George's respiratory questionnaire (SGRQ). Analyses were by intention to treat. This study is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12607000641493.

FINDINGS

71 patients were in the azithromycin group and 70 in the placebo group. The rate of event-based exacerbations was 0·59 per patient in the azithromycin group and 1·57 per patient in the placebo group in the 6-month treatment period (rate ratio 0·38, 95% CI 0·26-0·54; p<0·0001). Prebronchodilator FEV(1) did not change from baseline in the azithromycin group and decreased by 0·04 L in the placebo group, but the difference was not significant (0·04 L, 95% CI -0·03 to 0·12; p=0·251). Additionally, change in SGRQ total score did not differ between the azithromycin (-5·17 units) and placebo groups (-1·92 units; difference -3·25, 95% CI -7·21 to 0·72; p=0·108).

INTERPRETATION

Azithromycin is a new option for prevention of exacerbations in patients with non-cystic fibrosis bronchiectasis with a history of at least one exacerbation in the past year.

FUNDING

Health Research Council of New Zealand and Auckland District Health Board Charitable Trust.

Short- and long-term antibiotic treatment reduces airway and systemic inflammation in non-cystic fibrosis bronchiectasis

RATIONALE

The vicious cycle hypothesis of bronchiectasis argues that bacterial colonization leads to airway inflammation and progressive lung damage. The logical extension of this hypothesis is that acute or chronic antibiotic therapy should improve airway inflammation and clinical outcome. There are little data to support this hypothesis in patients with non-cystic fibrosis (CF) bronchiectasis.

OBJECTIVES

To determine whether acute or chronic antibiotic therapy improves airway inflammation and clinical outcome in non-CF bronchiectasis.

METHODS

The relationship between bacterial load and airway and systemic inflammation was investigated in 385 stable patients, 15 stable patients treated with intravenous antibiotics, and 34 patients with an exacerbation of bronchiectasis treated with intravenous antibiotics. Long-term antibiotic therapy was investigated using samples from a 12-month controlled trial of nebulized gentamicin.

MEASUREMENTS AND MAIN RESULTS

In stable patients, there was a direct relationship between airway bacterial load and markers of airway inflammation (P < 0.0001 for all analyses). High bacterial loads were associated with higher serum intercellular adhesion molecule-1, E-selectin, and vascular cell adhesion molecule-1 (P < 0.05 above bacterial load ≥1 × 10(7) cfu/ml). In stable patients, there was a direct relationship between bacterial load and the risk of subsequent exacerbations (odds ratio, 1.20; 95% confidence interval, 1.11-1.29; P < 0.0001) and severe exacerbations (odds ratio, 1.11; 95% confidence interval, 1.01-1.21; P = 0.02). Short- and long-term antibiotic treatments were associated with reductions in bacterial load, airways, and systemic inflammation.

CONCLUSIONS

High airway bacterial loads in non-CF bronchiectasis are associated with airway and systemic inflammation and a greater risk of exacerbations. Short- and long-term antibiotic therapy reduce markers of airways and systemic inflammation.

Pathogen- and host-directed anti-inflammatory activities of macrolide antibiotics

Macrolide antibiotics possess several, beneficial, secondary properties which complement their primary antimicrobial activity. In addition to high levels of tissue penetration, which may counteract seemingly macrolide-resistant bacterial pathogens, these agents also possess anti-inflammatory properties, unrelated to their primary antimicrobial activity. Macrolides target cells of both the innate and adaptive immune systems, as well as structural cells, and are beneficial in controlling harmful inflammatory responses during acute and chronic bacterial infection. These secondary anti-inflammatory activities of macrolides appear to be particularly effective in attenuating neutrophil-mediated inflammation. This, in turn, may contribute to the usefulness of these agents in the treatment of acute and chronic inflammatory disorders of both microbial and nonmicrobial origin, predominantly of the airways. This paper is focused on the various mechanisms of macrolide-mediated anti-inflammatory activity which target both microbial pathogens and the cells of the innate and adaptive immune systems, with emphasis on their clinical relevance.