The effect of telithromycin in acute exacerbations of asthma

Prevalence of acute infection in adults with asthma exacerbation: A systematic review and meta-analysis

BACKGROUND

Acute respiratory infections are a major trigger of asthma exacerbations. This study sought to estimate the overall proportion of viruses, atypical pathogens, and bacteria detected in adults with asthma exacerbations.

METHODS

PubMed, EMBASE, and Cochrane Library databases and all related studies from the reviews and references were searched from inception to February 13, 2020. Two authors independently performed study selection, data extraction, as well as quality evaluation. Subsequently, meta-analysis, between-study heterogeneity, and publication bias assessment were conducted on RStudio.

RESULTS

Forty-three eligible studies comprising 3511 adults were included, of which 21 publications mentioned multiple infections during acute asthma attacks. Meta-analysis showed an acute infection prevalence of 40.19% (95% confidence interval [CI] 34.53%-45.99%). Viruses, atypical pathogens, and bacteria were detected in 38.76% (95% CI 32.02%-45.71%), 8.29% (95% CI 2.64%-16.27%), and 7.05% (95% CI 3.34%-11.81%) of asthmatics during exacerbations, respectively. Rhinovirus infections are always the dominant trigger for exacerbations with a proportion of 20.02% (95% CI 14.84%-25.73%). Substantial heterogeneity across studies (Cochran Q test: 479.43, P < 0.0001, I2 = 91.2%) was explained by subgroup analysis, indicating that year, region, population, respiratory secretion, detection method, pathogen, and study quality were all influencing factors.

CONCLUSION

This meta-analysis provided the first quantitative epidemiological data for adults, and in the future, more research and health-care supports are necessary in this area.

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.

The epigenetic state of IL-4-polarized macrophages enables inflammatory cistromic expansion and extended synergistic response to TLR ligands

Prior exposure to microenvironmental signals could fundamentally change the response of macrophages to subsequent stimuli. It is believed that T helper-2 (Th2)-cell-type cytokine interleukin-4 (IL-4) and Toll-like receptor (TLR) ligand-activated transcriptional programs mutually antagonize each other, and no remarkable convergence has been identified between them. In contrast, here, we show that IL-4-polarized macrophages established a hyperinflammatory gene expression program upon lipopolysaccharide (LPS) exposure. This phenomenon, which we termed extended synergy, was supported by IL-4-directed epigenomic remodeling, LPS-activated NF-κB-p65 cistrome expansion, and increased enhancer activity. The EGR2 transcription factor contributed to the extended synergy in a macrophage-subtype-specific manner. Consequently, the previously alternatively polarized macrophages produced increased amounts of immune-modulatory factors both in vitro and in vivo in a murine Th2 cell-type airway inflammation model upon LPS exposure. Our findings establish that IL-4-induced epigenetic reprogramming is responsible for the development of inflammatory hyperresponsiveness to TLR activation and contributes to lung pathologies.

Carbazole Derivatives as Potential Antimicrobial Agents

Microbial infection is a leading cause of death worldwide, resulting in around 1.2 million deaths annually. Due to this, medicinal chemists are continuously searching for new or improved alternatives to combat microbial infections. Among many nitrogen-containing heterocycles, carbazole derivatives have shown significant biological activities, of which its antimicrobial and antifungal activities are the most studied. In this review, miscellaneous carbazole derivatives and their antimicrobial activity are discussed (articles published from 1999 to 2022).

Carbohydrate-based drugs launched during 2000-2021

Carbohydrates are fundamental molecules involved in nearly all aspects of lives, such as being involved in formating the genetic and energy materials, supporting the structure of organisms, constituting invasion and host defense systems, and forming antibiotics secondary metabolites. The naturally occurring carbohydrates and their derivatives have been extensively studied as therapeutic agents for the treatment of various diseases. During 2000 to 2021, totally 54 carbohydrate-based drugs which contain carbohydrate moities as the major structural units have been approved as drugs or diagnostic agents. Here we provide a comprehensive review on the chemical structures, activities, and clinical trial results of these carbohydrate-based drugs, which are categorized by their indications into antiviral drugs, antibacterial/antiparasitic drugs, anticancer drugs, antidiabetics drugs, cardiovascular drugs, nervous system drugs, and other agents.

Viral Infection and Airway Epithelial Immunity in Asthma

Viral respiratory tract infections are associated with asthma development and exacerbation in children and adults. In the course of immune responses to viruses, airway epithelial cells are the initial platform of innate immunity against viral invasion. Patients with severe asthma are more vulnerable than those with mild to moderate asthma to viral infections. Furthermore, in most cases, asthmatic patients tend to produce lower levels of antiviral cytokines than healthy subjects, such as interferons produced from immune effector cells and airway epithelial cells. The epithelial inflammasome appears to contribute to asthma exacerbation through overactivation, leading to self-damage, despite its naturally protective role against infectious pathogens. Given the mixed and complex immune responses in viral-infection-induced asthma exacerbation, this review examines the diverse roles of airway epithelial immunity and related potential therapeutic targets and discusses the mechanisms underlying the heterogeneous manifestations of asthma exacerbations.

Antibiotic Use in Paediatric Patients Hospitalized with Acute Severe Asthma

BACKGROUND

Antibiotic use during asthma exacerbations in paediatric patients is not routinely recommended but common practise in out-patient and in-patient settings. Objective of this study was to analyse frequency of antibiotic use during acute severe asthma exacerbations, antibiotic classes utilized and clinical decision-making.

METHODS

All in-patient admissions over 10 years in a single German Children's University hospital due to acute severe asthma were included in this retrospective analysis. Age, length of stay, oxygen supplementation, treatment, laboratory parameters and chest x-rays of all patients ranging from 1 to 17 years were analysed.

RESULTS

580 hospital admissions were included in this study. Overall antibiotic use was high but decreased with age (1-5 years 69,6%, 6-11 years 57,6% and 12-17 years 39,7%, p<0.001). Analysis of antibiotic treatment without clear indication showed a consistently lower treatment rate of 28.3%, with macrolides being the most common antibiotic class. Younger age significantly decreased, whereas, increase of CrP value, use of oxygen supplementation and concomitant fever all significantly increased the odds ratio (OR 0.967; 4.366, 2.472 and 2.011 respectively) of receiving antibiotic treatment without clear indication.

CONCLUSION

Antibiotic treatment without clear indication during acute severe asthma is common in this German single-centre cohort. Clinical parameters of more severe disease affect clinician's decision to administer antibiotics despite evidence of bacterial infection or improved outcome.

Prevention and Outpatient Treatment of Asthma Exacerbations in Children

Acute exacerbations cause significant morbidity and mortality in children with asthma worldwide. Although exacerbations can be minor and transient, in some children they are recurrent and significantly adversely impact quality of life. Children with frequent exacerbations account for a disproportionate amount of unscheduled care in nonprimary health facilities. Frequent exacerbators are often prescribed controller medications, but poor adherence is common. Major predictors for asthma exacerbations include genetic, social, comorbid, biological, and environmental factors. Although virus infections are a key trigger for exacerbations, other environmental factors also significantly increase risk. A previous exacerbation is a major risk factor for future exacerbations and thus identifies children to target for prevention of future episodes. In this review, we discuss both modifiable and fixed factors associated with asthma exacerbations, how to assess children for risk, and which pharmacological and nonpharmacological interventions may be of benefit. Finally, we review the current evidence around treatment within the outpatient setting for an emerging exacerbation.

A real-life comparative effectiveness study into the addition of antibiotics to the management of asthma exacerbations in primary care

BACKGROUND

Asthma exacerbations are major contributors to asthma morbidity and mortality. They are usually managed with bronchodilators and oral corticosteroids (OCS), but clinical trial evidence suggests that antibiotics could be beneficial. We aimed to assess whether treatment of asthma exacerbations with antibiotics in addition to OCS improved outcomes in larger, more representative routine-care populations.

METHOD

A retrospective comparative effectiveness study into managing asthma exacerbations with OCS alone versus OCS plus antibiotics was conducted using the Optimum Patient Care Research Database. The dataset included 28 637 patients; following propensity score matching 20 024 adults and 4184 children were analysed.

RESULTS

Antibiotics in addition to OCS were prescribed for the treatment of asthma exacerbations in 45% of adults and 32% of children. Compared to OCS alone, OCS plus antibiotics was associated with reduced risk of having an asthma/wheeze consultation in the following 2 weeks (children hazard ratio (HR) 0.84 (95% CI 0.73-0.96), p=0.012; adults HR 0.86 (95% CI 0.81-0.91), p<0.001), but an increase in risk of a further OCS prescription for a new/ongoing exacerbation within 6 weeks in adults (HR 1.11 (95% CI 1.01-1.21), p=0.030), but not children. Penicillins, but not macrolides, were associated with a reduction in the odds of a subsequent asthma/wheeze consultation compared to OCS alone, in both adults and children.

CONCLUSION

Antibiotics were frequently prescribed in relation to asthma exacerbations, contrary to guideline recommendations. Overall, the routine addition of antibiotics to OCS in the management of asthma exacerbations appeared to confer little clinical benefit, especially when considering the risks of antibiotic overuse.

Chlamydia pneumoniae and chronic asthma: Updated systematic review and meta-analysis of population attributable risk

Background

Chlamydia pneumoniae (Cp) is an obligate intracellular human respiratory pathogen producing persisting lung infection with a plausible link to asthma pathogenesis. The population attributable risk of potentially treatable Cp infection in asthma has not been reported.

Methods

The author searched from 2000 to 2020 inclusive for previously un-reviewed and new cross sectional and prospective controlled studies of Cp biomarkers and chronic asthma in both children and adults. Qualitative descriptive results and quantitative estimates of population attributable risk for selected biomarkers (specific IgG, IgA and IgE) are presented.

Findings

No large, long-term prospective population-based studies of Cp infection and asthma were identified. About half of case-control studies reported one or more significant associations of Cp biomarkers and chronic asthma. Heterogeneity of results by age group (pediatric v adult asthma), severity category (severe/uncontrolled, moderate/partly controlled, mild/controlled) and antibody isotype (specific IgG, IgA, IgE) were suggested by the qualitative results and confirmed by meta-analyses. The population attributable risks for Cp-specific IgG and IgA were nul in children and were 6% (95% confidence interval 2%-10%, p = 0.002) and 13% (9%-18%, p<0.00001) respectively in adults. In contrast to the nul or small population attributable risks for Cp-specific IgG and IgA, the population attributable risk for C. pneumoniae-specific IgE (children and adults combined) was 47% (39%-55%, p<0.00001). In the subset of studies that reported on asthma severity categories, Cp biomarkers were positively and significantly (P<0.00001) associated with asthma severity.

Interpretation

C. pneumoniae-specific IgE is strongly associated with asthma and asthma severity, suggesting a possible mechanism linking chronic Cp infection with asthma in a subset of individuals with asthma. Infection biomarkers should be included in future macrolide treatment trials for severe and uncontrolled asthma.

Azithromycin in viral infections

Azithromycin (AZM) is a synthetic macrolide antibiotic effective against a broad range of bacterial and mycobacterial infections. Due to an additional range of anti-viral and anti-inflammatory properties, it has been given to patients with the coronaviruses SARS-CoV or MERS-CoV. It is now being investigated as a potential candidate treatment for SARS-CoV-2 having been identified as a candidate therapeutic for this virus by both in vitro and in silico drug screens. To date there are no randomised trial data on its use in any novel coronavirus infection, although a large number of trials are currently in progress. In this review, we summarise data from in vitro, murine and human clinical studies on the anti-viral and anti-inflammatory properties of macrolides, particularly AZM. AZM reduces in vitro replication of several classes of viruses including rhinovirus, influenza A, Zika virus, Ebola, enteroviruses and coronaviruses, via several mechanisms. AZM enhances expression of anti-viral pattern recognition receptors and induction of anti-viral type I and III interferon responses. Of relevance to severe coronavirus-19 disease (COVID-19), which is characterised by an over-exuberant innate inflammatory response, AZM also has anti-inflammatory properties including suppression of IL-1beta, IL-2, TNF and GM-CSF. AZM inhibits T cells by inhibiting calcineurin signalling, mammalian target of rapamycin activity and NFκB activation. AZM particularly targets granulocytes where it concentrates markedly in lysosomes, particularly affecting accumulation, adhesion, degranulation and apoptosis of neutrophils. Given its proven safety, affordability and global availability, tempered by significant concerns about antimicrobial stewardship, there is an urgent mandate to perform well-designed and conducted randomised clinical trials.

Recent Practice Patterns and Variations in Children Hospitalized for Asthma Exacerbation in Japan

BACKGROUND

High antibiotic prescribing rates for adults with an asthma exacerbation have been reported in developed countries, but few studies have assessed the variation of antibiotic and adjunctive treatment in the routine care of children.

OBJECTIVE

We evaluated the trends in health resource utilization for children hospitalized for asthma exacerbation, ascertained the variations of practices across hospitals and geographic location, and classified these different patterns at hospital levels.

METHODS

Using data on Japanese children hospitalized for asthma exacerbation with no indication of bacterial infection during 2010-2018, we conducted a retrospective observational study to assess the trends in initial treatment patterns and their variations. Mixed-effect generalized linear models were used to investigate the treatment trends. Hierarchical cluster analyses were performed to classify the treatment variations across hospitals.

RESULTS

Overall, 54,981 children were eligible for the study. Proportions of antibiotic use decreased from 47.2% in 2010 to 26.9% in 2018. Similarly, utilization of antitussives, antihistamines, and methylxanthine showed decreasing trends over the period, whereas the use of mucolytics and ambroxol increased. These treatment variations were more considerable in hospital levels than in 47 prefecture levels. Hierarchical cluster analyses classified these patterns into 6 groups, mostly based on mediator release inhibitor, ambroxol, and antitussives.

CONCLUSIONS

Wide variations in antibiotics and adjunctive treatments were observed across hospital levels. Our findings support the improvement in reducing inappropriate antibiotic use and highlight the need for comparative effectiveness research of the adjunctive treatments among children hospitalized for asthma.

The impact of budesonide inhalation suspension for asthma hospitalization: In terms of length of stay, recovery time from symptoms, and hospitalization costs

BACKGROUND

Hospitalization is a major cause of medical expenditure for asthma. Budesonide inhalation suspension (BIS) may assist in reducing asthma-related symptoms in severe asthma exacerbation. However, its effectiveness for hospitalized patients remains poorly known. The objective of this study is to determine associations of BIS with asthma hospitalization.

METHODS

We retrospectively analyzed 98 patients who were admitted to our hospital due to severe asthma exacerbation (24 treated with BIS in combination with procaterol) from April 2014 to January 2019. Length of stay, recovery time from symptoms (wheezes), and hospitalization costs were compared between the 2 groups according to clinical factors including the use of BIS and sings of respiratory infections (i.e. C-reactive protein, the presence of phlegm, and the use of antibiotics). Multivariate logistic regression analysis was performed to determine factors contributing to hospitalization outcomes.

RESULTS

The use of BIS was associated with shorter length of stay, faster recovery time from symptoms, and more reduced hospitalization costs (6.0 vs 8.5 days, 2.5 vs 5.0 days, and 258,260 vs 343,350 JPY). Signs of respiratory infection were also associated with hospitalization outcomes. On a multivariate regression analysis, the use of BIS was a determinant of shortened length of stay and reduced symptoms and medical costs for asthma hospitalization along with signs of respiratory infection.

CONCLUSIONS

BIS may contribute to shorten length of hospital stay and to reduce symptoms and medical expenditure irrespective of the presence or absence of respiratory infection.

Association between early antibiotic treatment and clinical outcomes in children hospitalized for asthma exacerbation

BACKGROUND

Professional society guidelines recommend against routine early antibiotic use in the treatment of asthma exacerbation without comorbid bacterial infection. However, high antibiotic prescribing rates have been reported in developed countries.

OBJECTIVE

We sought to assess the effectiveness of this strategy in the routine care of children.

METHODS

Using data on 48,743 children hospitalized for asthma exacerbation with no indication of bacterial infection during the period 2010 to 2018, we conducted a retrospective cohort study to compare clinical outcomes and resource utilization between children who received early antibiotic treatment and those who did not.

RESULTS

Overall, 19,866 children (41%) received early antibiotic treatment. According to the propensity score matching analysis, children with early antibiotic treatment had longer hospital stay (mean difference, 0.21 days; 95% CI, 0.18-0.28), higher hospitalization costs (mean difference, $83.5; 95% CI, 62.9-104.0), and higher risk of probiotic use (risk ratio, 2.01; 95% CI, 1.81-2.23) than children who did not receive early antibiotic therapy. Similar results were found from inverse probability of treatment weighting, g-computation, and instrumental variable methods and sensitivity analyses. The risks of mechanical ventilation and 30-day readmission were similar between the groups or slightly higher in the treated group, depending on the statistical models.

CONCLUSIONS

Antibiotic therapy may be associated with prolonged hospital stay, elevated hospitalization costs, and high risk of probiotic use without improving treatment failure and readmission. Our findings highlight the need for reducing inappropriate antibiotic use among children hospitalized for asthma.

Mechanisms and Management of Asthma Exacerbations

Acute asthma remains an important medical emergency, the most frequent cause of acute admissions in children and a major source of morbidity for adults with asthma. In all ages with asthma, the presence of exacerbations is an important defining characteristic of asthma severity. In this review, we assess the epidemiology of acute asthma, the triggers of acute exacerbations, and the mechanisms that underlie these exacerbations. We also assess current treatments that prevent exacerbations, with an emphasis on the role of type 2 airway inflammation in the context of acute exacerbations and the novel treatments that effectively target this. Finally we review current management strategies of the exacerbations themselves.

Management of severe asthma exacerbation: guidelines from the Société Française de Médecine d'Urgence, the Société de Réanimation de Langue Française and the French Group for Pediatric Intensive Care and Emergencies

BACKGROUND

The French Emergency Medicine Society, the French Intensive Care Society and the Pediatric Intensive Care and Emergency Medicine French-Speaking Group edited guidelines on severe asthma exacerbation (SAE) in adult and pediatric patients.

RESULTS

The guidelines were related to 5 areas: diagnosis, pharmacological treatment, oxygen therapy and ventilation, patients triage, specific considerations regarding pregnant women. The literature analysis and formulation of the guidelines were conducted according to the Grade of Recommendation Assessment, Development and Evaluation methodology. An extensive literature research was conducted based on publications indexed in PubMed™ and Cochrane™ databases. Of the 21 formalized guidelines, 4 had a high level of evidence (GRADE 1+/-) and 7 a low level of evidence (GRADE 2+/-). The GRADE method was inapplicable to 10 guidelines, which resulted in expert opinions. A strong agreement was reached for all guidelines.

CONCLUSION

The conjunct work of 36 experts from 3 scientific societies resulted in 21 formalized recommendations to help improving the emergency and intensive care management of adult and pediatric patients with SAE.

A host gene expression approach for identifying triggers of asthma exacerbations

Rationale

Asthma exacerbations often occur due to infectious triggers, but determining whether infection is present and whether it is bacterial or viral remains clinically challenging. A diagnostic strategy that clarifies these uncertainties could enable personalized asthma treatment and mitigate antibiotic overuse.

Objectives

To explore the performance of validated peripheral blood gene expression signatures in discriminating bacterial, viral, and noninfectious triggers in subjects with asthma exacerbations.

Methods

Subjects with suspected asthma exacerbations of various etiologies were retrospectively selected for peripheral blood gene expression analysis from a pool of subjects previously enrolled in emergency departments with acute respiratory illness. RT-PCR quantified 87 gene targets, selected from microarray-based studies, followed by logistic regression modeling to define bacterial, viral, or noninfectious class. The model-predicted class was compared to clinical adjudication and procalcitonin.

Results

Of 46 subjects enrolled, 7 were clinically adjudicated as bacterial, 18 as viral, and 21 as noninfectious. Model prediction was congruent with clinical adjudication in 15/18 viral and 13/21 noninfectious cases, but only 1/7 bacterial cases. None of the adjudicated bacterial cases had confirmatory microbiology; the precise etiology in this group was uncertain. Procalcitonin classified only one subject in the cohort as bacterial. 47.8% of subjects received antibiotics.

Conclusions

Our model classified asthma exacerbations by the underlying bacterial, viral, and noninfectious host response. Compared to clinical adjudication, the majority of discordances occurred in the bacterial group, due to either imperfect adjudication or model misclassification. Bacterial infection was identified infrequently by all classification schemes, but nearly half of subjects were prescribed antibiotics. A gene expression-based approach may offer useful diagnostic information in this population and guide appropriate antibiotic use.

Azithromycin treatment in children hospitalized with asthma: a retrospective cohort study

Objective: Azithromycin has anti-inflammatory properties in the lungs and decreases the duration of asthma-like episodes in children. We sought to evaluate length of stay (LOS) and readmission rates of children receiving azithromycin therapy during hospitalization for acute asthma exacerbations.Methods: This was a retrospective cohort study at an urban, quaternary-care children's hospital including patients under 18 years old hospitalized for asthma, without concurrent infection, from 2002 to 2011. The primary predictor was azithromycin therapy administered within 48 hours of admission. The primary outcome was LOS and the secondary outcomes were 7, 30, and 90-day hospital readmission rates for asthma.Results: Azithromycin therapy was administered to 174 (3%) of 5335 unique patients admitted for asthma, without concurrent infection, over the 10-year period. The overall median LOS was 2.3 days [Interquartile range, 1.8-3.1] and 9% (480) were readmitted for asthma within 90 days of discharge. Azithromycin therapy was associated with a 20% (11 hour) longer LOS (adjusted beta coefficient for log-transformed LOS, 0.18; 95% Confidence Interval (CI): 0.11-0.26), less than the 29% (16 hour) difference determined a priori as clinically relevant. Azithromycin therapy was not associated with 90-day readmission for asthma (adjusted odds ratio, 0.89; 95% CI: 0.46-1.72]. The limited number of 7 and 30-day readmissions in the azithromycin treated group precluded adjusted analysis.Conclusions: Azithromycin therapy was not associated with a clinically relevant difference in hospital LOS or with readmission rates for children hospitalized with asthma. Prospective trials are needed to determine the clinical effects of azithromycin therapy in children with asthma.

A review of non-cystic fibrosis bronchiectasis in children with a focus on the role of long-term treatment with macrolides

Bronchiectasis is a rare chronic airway disease arising from several respiratory and systemic diseases. The grade of evidence for specific treatment of childhood bronchiectasis unrelated to cystic fibrosis (CF) is low with very few randomized controlled trials. Treatment has been based mainly on evidence from studies in adults with non-cystic fibrosis bronchiectasis and patients with cystic fibrosis. Recently, long-term treatment with macrolides has been proposed. These molecules offer the advantage of anti-inflammatory and immunomodulatory properties in addition to their antibacterial properties. A total of three randomized double-blind placebo-controlled trials conducted in adults showed that macrolides taken for 6-12 months led to a significant reduction in exacerbation rates. Only one long-term, randomized double-blind placebo-controlled trial was conducted in the pediatric population. It showed that azithromycin administered weekly for up to 24 months reduced pulmonary exacerbations. Further randomized controlled studies are needed to determine the optimal dose and duration of treatment with macrolides. The clinical profile of children who would benefit from this treatment also needs to be determined.

Association of Antibiotic Treatment With Outcomes in Patients Hospitalized for an Asthma Exacerbation Treated With Systemic Corticosteroids

IMPORTANCE

Although professional society guidelines discourage use of empirical antibiotics in the treatment of asthma exacerbation, high antibiotic prescribing rates have been recorded in the United States and elsewhere.

OBJECTIVE

To determine the association of antibiotic treatment with outcomes among patients hospitalized for asthma and treated with corticosteroids.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of data of 19 811 adults hospitalized for asthma exacerbation and treated with systemic corticosteroids in 542 US acute care hospitals from January 1, 2015, through December 31, 2016.

EXPOSURES

Early antibiotic treatment, defined as an treatment with an antibiotic initiated during the first 2 days of hospitalization and prescribed for a minimum of 2 days.

MAIN OUTCOMES AND MEASURES

The primary outcome measure was hospital length of stay. Other measures were treatment failure (initiation of mechanical ventilation, transfer to the intensive care unit after hospital day 2, in-hospital mortality, or readmission for asthma) within 30 days of discharge, hospital costs, and antibiotic-related diarrhea. Multivariable adjustment, propensity score matching, propensity weighting, and instrumental variable analysis were used to assess the association of antibiotic treatment with outcomes.

RESULTS

Of the 19 811 patients, the median (interquartile range [IQR]) age was 46 (34-59) years, 14 389 (72.6%) were women, 8771 (44.3%) were white, and Medicare was the primary form of health insurance for 5120 (25.8%). Antibiotics were prescribed for 8788 patients (44.4%). Compared with patients not treated with antibiotics, treated patients were older (median [IQR] age, 48 [36-61] vs 45 [32-57] years), more likely to be white (48.6% vs 40.9%) and smokers (6.6% vs 5.3%), and had a higher number of comorbidities (eg, congestive heart failure, 6.2% vs 5.8%). Those treated with antibiotics had a significantly longer hospital stay (median [IQR], 4 [3-5] vs 3 [2-4] days) and a similar rate of treatment failure (5.4% vs 5.8%). In propensity score-matched analysis, receipt of antibiotics was associated with a 29% longer hospital stay (length of stay ratio, 1.29; 95% CI, 1.27-1.31) and higher cost of hospitalization (median [IQR] cost, $4776 [$3219-$7373] vs $3641 [$2346-$5942]) but with no difference in the risk of treatment failure (propensity score-matched OR, 0.95; 95% CI, 0.82-1.11). Multivariable adjustment, propensity score weighting, and instrumental variable analysis as well as several sensitivity analyses yielded similar results.

CONCLUSIONS AND RELEVANCE

Antibiotic therapy may be associated with a longer hospital length of stay, higher hospital cost, and similar risk of treatment failure. These results highlight the need to reduce inappropriate antibiotic prescribing among patients hospitalized for asthma.

The effects of macrolides in children with reactive airway disease: a systematic review and meta-analysis of randomized controlled trials

Purpose

Childhood reactive airway diseases (RADs) are concerning problems in children’s airways and may be preceded by bronchiolitis and may progress to childhood asthma. The severity of the disease is indicated by deterioration in pulmonary functions, increased usage of rescue medications, and recurrent wheezing episodes. Macrolides have both antimicrobial and anti-inflammatory functions and have been used as adjunctive therapy in childhood RADs.

Patients and methods

We conducted a meta-analysis to evaluate the effect of macrolides in children with RAD. Literature searches were systematically conducted using an electronic database from inception to August 2018. The Cochrane review risk of bias assessment tool was used to assess the quality of each randomized controlled trial.

Results

Sixteen randomized controlled trials comprising 1,415 participants were investigated in this meta-analysis. Children treated with macrolide therapy showed significantly better pulmonary functions in both forced expiratory volume in one second (% predicted) (difference in means=−9.77, 95% CI=−14.18 to −5.35, P<0.001; I²=0%) and forced expiratory flow 25–75 (% predicted) (difference in means=−14.14, 95% CI=−26.11 to −2.18, P=0.02; I²=29.56%). In addition, the short-acting β-agonist usage days and recurrent wheezing risk were significantly lowered in children with macrolide treatment (standardized difference in means=−0.34, 95% CI=−0.59 to −0.09, P=0.007, I²=27.05% and standardized difference in means=−0.53, 95% CI=−0.81 to −0.26, P<0.001, I²=0%, respectively). Furthermore, the growth of Moraxella catarrhalis from nasal swabs was less in children treated with macrolides (odds ratio=0.19, 95% CI=0.11–0.35, P<0.001). Children who took macrolides had a lower risk of adverse events (risk ratio=0.83, 95% CI=0.70–0.98, P=0.024, I²=0%).

Conclusion

This current meta-analysis suggested that adjunctive therapy with macrolides is safe and effective for achieving better outcomes in childhood RAD.

The asthma Symptom Free Days Questionnaire: how reliable are patient responses?

Objective: Symptom free days are a widely used patient-reported outcome (PRO) in asthma clinical trials. We assessed the internal consistency of one instrument for this PRO, the Symptom Free Days Questionnaire (SFDQ), in a population of Black adults with asthma enrolled in the Blacks and Exacerbations on Long-acting beta agonists and Tiotropium (BELT) trial. Methods: We assessed responses to the SFDQ collected at baseline, 6 and 12 months as part of the BELT trial. The internal consistency of responses, specifically number of patient-reported days with symptoms in 14 days were compared to the number of patient-reported days with no symptoms in the same 14 days. Lin concordance correlation coefficients (Lin ccc) were calculated over time to assess "learning" and by age, sex, geographic location, and annual family income. Results: The internal consistency of the responses of the 1070 enrolled patients was consistently low over the 12 months of the study; varying from 43.8% at baseline to 52.1% at 12 months. This corresponded to Lin cccs of 0.33-0.32 over the study period. Internal consistency and the Lin ccc did not vary by age group, sex, geographic location or percent poverty. Concordance was slightly but not significantly higher at all time points in those with family annual income of ≥$50,000 compared to those with lower annual incomes. Conclusions: The SFDQ did not work well in the BELT population of Black adults with asthma. Further validation is required before the SFDQ is used in other large clinical trials with any population.

Antibiotics and autoimmune and allergy diseases: Causative factor or treatment?

The newborn infant emerges from an almost sterile environment into a world of bacteria. Bacteria colonize the infant's skin, lungs, and, of most importance, the gut. The process of bacterial colonization is coordinated, and each body niche acquires a unique composition of bacteria. In the gut, most bacteria belong to the Firmicutes and Bacteroidetes phyla, while Actinobacteria and Proteobacteria are far less abundant. Some of these bacteria possess strong immunoregulatory properties. Bacterial colonization is essential to skew the newborn's immune response away from the allergy-favoring Type-2 response towards a Type-1 immune response, which is essential for pathogen elimination. Imbalance between Type 1 and Type 2 responses, however, can promote autoimmunity. In addition, the microbiota shapes immune responses in adults. Autoimmune and allergic diseases are commonly associated with an altered composition of resident bacteria, which is known as dysbiosis. Perhaps the most common cause of disruption and alteration of the bacterial colonization of newborns is the use of antibiotics. It is not known whether the dysbiosis precedes or is the consequence of allergic and autoimmune disorders, and whether antibiotics can be a trigger for these disorders, depending on the type of antibiotic used and the maturity of immune system. In this review, we discuss the development of the microbiota in different body niches and their immunomodulatory potential. We evaluate the impact of antibiotics, both in mice and in humans, on microbial communities and how that may impact the development and manifestation of diseases through all stages of life: the prenatal period, childhood, and adulthood.

Does antibiotic treatment duration affect the outcomes of exacerbations of asthma and COPD? A systematic review

Asthma and chronic obstructive pulmonary disease (COPD) cause significant morbidity and mortality worldwide, primarily through exacerbations. Exacerbations are often treated with antibiotics but their optimal course duration is uncertain. Reducing antibiotic duration may influence antimicrobial resistance but risks treatment failure. The objective of this article is to review published literature to investigate whether shorter antibiotic therapy duration affects clinical outcomes in the treatment of asthma and COPD exacerbations. We systematically searched electronic databases (MEDLINE, EMBASE, CINAHL, World Health Organisation International Clinical Trial Registry Platform, the Cochrane library, and ISRCTN) with no language, location, or time restrictions. We retrieved observational and controlled trials comparing different durations of the same oral antibiotic therapy in the treatment of acute exacerbations of asthma or COPD in adults. We found no applicable studies for asthma exacerbations. We included 10 randomized, placebo-controlled trials for COPD patients, all from high-income countries. The commonest studied antibiotic class was fluoroquinolones. Antibiotic courses shorter than 6 days were associated with significantly fewer overall adverse events (risk ratio (RR): 0.84, 95% confidence interval (CI): 0.75-0.93, p = 0.001) when compared with those of 7 or more days. There was no statistically significant difference for clinical success or bacteriological eradication in sputum (RR: 1.00, 95% CI: 0.88-1.13 and RR: 1.06, 95% CI: 0.79-1.44, respectively). Shorter durations of antibiotics for COPD exacerbations do not seem to confer a higher risk of treatment failure but are associated with fewer adverse events. This is in keeping with previous studies in community acquired pneumonia, but studies were heterogeneous and differed from usual clinical practice. Further observational and prospective work is needed to explore the significance of antibiotic duration in the treatment of asthma and COPD exacerbations.

Antibiotics for exacerbations of asthma

BACKGROUND

Asthma is a chronic respiratory condition that affects over 300 million adults and children worldwide. It is characterised by wheeze, cough, chest tightness, and shortness of breath. Symptoms typically are intermittent and may worsen over a short time, leading to an exacerbation. Asthma exacerbations can be serious, leading to hospitalisation or even death in rare cases. Exacerbations may be treated by increasing an individual's usual medication and providing additional medication, such as oral steroids. Although antibiotics are sometimes included in the treatment regimen, bacterial infections are thought to be responsible for only a minority of exacerbations, and current guidance states that antibiotics should be reserved for cases in which clear signs, symptoms, or laboratory test results are suggestive of bacterial infection.

OBJECTIVES

To determine the efficacy and safety of antibiotics in the treatment of asthma exacerbations.

SEARCH METHODS

We searched the Cochrane Airways Trials Register, which contains records compiled from multiple electronic and handsearched resources. We also searched trial registries and reference lists of primary studies. We conducted the most recent search in October 2017.

SELECTION CRITERIA

We included studies comparing antibiotic therapy for asthma exacerbations in adults or children versus placebo or usual care not involving an antibiotic. We allowed studies including any type of antibiotic, any dose, and any duration, providing the aim was to treat the exacerbation. We included parallel studies of any duration conducted in any setting and planned to include cluster trials. We excluded cross-over trials. We included studies reported as full-text articles, those published as abstracts only, and unpublished data.

DATA COLLECTION AND ANALYSIS

At least two review authors screened the search results for eligible studies. We extracted outcome data, assessed risk of bias in duplicate, and resolved discrepancies by involving another review author. We analysed dichotomous data as odds ratios (ORs) or risk differences (RDs), and continuous data as mean differences (MDs), all with a fixed-effect model. We described skewed data narratively. We graded the results and presented evidence in 'Summary of findings' tables for each comparison. Primary outcomes were intensive care unit/high dependence unit (ICU/HDU) admission, duration of symptoms/exacerbations, and all adverse events. Seconday outcomes were mortality, length of hospital admission, relapse after index presentation, and peak expiratory flow rate (PEFR).

MAIN RESULTS

Six studies met our inclusion criteria and included a total of 681 adults and children with exacerbations of asthma. Mean age in the three studies in adults ranged from 36.2 to 41.2 years. The three studies in children applied varied inclusion criteria, ranging from one to 18 years of age. Five studies explicitly excluded participants with obvious signs and symptoms of bacterial infection (i.e. those clearly meeting current guidance to receive antibiotics). Four studies investigated macrolide antibiotics, and two studies investigated penicillin (amoxicillin and ampicillin) antibiotics; both studies using penicillin were conducted over 35 years ago. Five studies compared antibiotics versus placebo, and one was open-label. Study follow-up ranged from one to twelve weeks. Trials were of varied methodological quality, and we were able to perform only limited meta-analysis.None of the included trials reported ICU/HDU admission, although one participant in the placebo group of a study including children with status asthmaticus experienced a respiratory arrest and was ventilated. Four studies reported asthma symptoms, but we were able to combine results for only two macrolide studies of 416 participants; the MD in diary card symptom score was -0.34 (95% confidence interval (CI) -0.60 to -0.08), with lower scores (on a 7 point scale) denoting improved symptoms. Two macrolide studies reported symptom-free days. One study of 255 adults authors reported the percentage of symptom-free days at 10 days as 16% in the antibiotic group and 8% in the placebo group. In a further study of 40 children study authors reported significantly more symptom-free days at all time points in the antibiotic group compared with the usual care group. The same study reported the duration in days of the index asthma exacerbation, again favouring the antibiotic group. One study of a penicillin including 69 participants reported asthma symptoms at hospital discharge; the between-group difference for both studies was reported as non-significant.We combined data for serious adverse events from three studies involving 502 participants, but events were rare; the three trials reported only 10 events: five in the antibiotic group and five in the placebo group. We combined data for all adverse events (AEs) from three studies, but the effect estimate is imprecise (OR 0.99, 95% CI 0.69 to 1.43). No deaths were reported in any of the included studies.Two studies investigating penicillins reported admission duration; neither study reported a between-group difference. In one study (263 participants) of macrolides, two participants in each arm were reported as experiencing a relapse, defined as a further exacerbation, by the six-week time points. We combined PEFR endpoint results at 10 days for two macrolide studies; the result favoured antibiotics over placebo (MD 23.42 L/min, 95% CI 5.23 to 41.60). One study in children reported the maximum peak flow recorded during the follow-up period, favouring the clarithromycin group, but the confidence interval includes no difference (MD 38.80, 95% CI -11.19 to 88.79).Grading of outcomes ranged from moderate to very low quality, with quality of outcomes downgraded for suspicion of publication bias, indirectness, imprecision, and poor methodological quality of studies.

AUTHORS' CONCLUSIONS

We found limited evidence that antibiotics given at the time of an asthma exacerbation may improve symptoms and PEFR at follow-up compared with standard care or placebo. However, findings were inconsistent across the six heterogeneous studies included, two of the studies were conducted over 30 years ago and most of the participants included in this review were recruited from emergency departments, limiting the applicability of findings to this population. Therefore we have limited confidence in the results. We found insufficient evidence about several patient-important outcomes (e.g. hospital admission) to form conclusions. We were unable to rule out a difference between groups in terms of all adverse events, but serious adverse events were rare.

Biological exacerbation clusters demonstrate asthma and chronic obstructive pulmonary disease overlap with distinct mediator and microbiome profiles

Background

Exacerbations of asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous.

Objective

We sought to investigate the sputum cellular, mediator, and microbiome profiles of both asthma and COPD exacerbations.

Methods

Patients with severe asthma or moderate-to-severe COPD were recruited prospectively to a single center. Sputum mediators were available in 32 asthmatic patients and 73 patients with COPD assessed at exacerbation. Biologic clusters were determined by using factor and cluster analyses on a panel of sputum mediators. Patterns of clinical parameters, sputum mediators, and microbiome communities were assessed across the identified clusters.

Results

The asthmatic patients and patients with COPD had different clinical characteristics and inflammatory profiles but similar microbial ecology. Three exacerbation biologic clusters were identified. Cluster 1 was COPD predominant, with 27 patients with COPD and 7 asthmatic patients exhibiting increased blood and sputum neutrophil counts, proinflammatory mediators (IL-1β, IL-6, IL-6 receptor, TNF-α, TNF receptors 1 and 2, and vascular endothelial growth factor), and proportions of the bacterial phylum Proteobacteria. Cluster 2 had 10 asthmatic patients and 17 patients with COPD with increased blood and sputum eosinophil counts, type 2 mediators (IL-5, IL-13, CCL13, CCL17, and CCL26), and proportions of the bacterial phylum Bacteroidetes. Cluster 3 had 15 asthmatic patients and 29 patients with COPD with increased type 1 mediators (CXCL10, CXCL11, and IFN-γ) and proportions of the phyla Actinobacteria and Firmicutes.

Conclusions

A biologic clustering approach revealed 3 subgroups of asthma and COPD exacerbations, each with different percentages of patients with overlapping asthma and COPD. The sputum mediator and microbiome profiles were distinct between clusters.

Doxycycline suppresses Chlamydia pneumoniae induced interferon-gamma responses in peripheral blood mononuclear cells in children with allergic asthma

Persistent respiratory infections caused by Chlamydia pneumoniae have been implicated in the pathogenesis of chronic diseases (e.g. asthma). Antibiotics are used to treat C. pneumoniae respiratory infections; however, the use of antibiotics as anti-inflammatory agents in treatment of asthma remains controversial. The current study investigated whether ciprofloxacin, azithromycin, or doxycycline can suppress C. pneumoniae-induced production of immunoglobulin (Ig) E or cytokines in peripheral blood mononuclear cells (PBMC) obtained from asthmatic children. Apart from blood, nasopharyngeal swab specimens were also collected to test for the presence of C. pneumoniae and/or M. pneumoniae (qPCR). PBMC (1.5 x 10⁶) from asthmatic pediatric patients (N = 18) were infected or mock infected for 1 h ± C. pneumoniae AR-39 at a multiplicity of infection (MOI) = 0.1, and cultured ± ciprofloxacin, azithromycin, or doxycycline (0.1 or 1.0 μg/mLmL) for either 48 h (cytokines) or 10 days (IgE). Interleukin (IL)-4, interferon (IFN)-γ and IgE levels in supernatants were measured (ELISA). When PBMC were infected with C. pneumoniae, IL-4 and IFNγ production increased (p = 0.06 and 0.03, respectively); IgE levels were low. The now-elevated levels of IL-4 didn't decrease significantly after addition of ciprofloxacin, azithromycin, or doxycycline. However, infected PBMC IFNγ formation decreased significantly when 0.1 μg/mL doxycycline was employed (p = 0.04); no dose of ciprofloxacin or azithromycin had any impact. This inhibitory outcome with doxycycline lends support to the use of tetracyclines as immune modulators and anti-inflammatory medications in treatment of C. pneumoniae-infected asthma patients.

Macrolides in Children With Community-Acquired Pneumonia: Panacea or Placebo?

Pneumonia, most often caused by a respiratory virus, is common in childhood. Mycoplasma pneumoniae also is detected frequently, particularly in older children in the era of pneumococcal conjugate vaccination. Despite recommendations for β-lactam antibiotics, macrolide antibiotics, including erythromycin, clarithromycin, and azithromycin, are prescribed frequently to children with acute lower respiratory infection. However, the significance of detecting "atypical" pathogens, including M pneumoniae, in children remains contentious. Considering the potential for antibacterial and anti-inflammatory activities of macrolides, our understanding of the role of these drugs in acute and chronic infections and in inflammatory conditions is changing. Some observational data have revealed improved outcomes in adults and children with pneumonia who are prescribed macrolides, although its widespread use has led to increases in macrolide resistance in Streptococcus pneumoniae and M pneumoniae. Clinical trials to define the role of macrolides in pediatric acute respiratory infection must be prioritized.

Detection of pathogens by real-time PCR in adult patients with acute exacerbation of bronchial asthma

BACKGROUND

Respiratory tract infection is a major cause of acute exacerbation of bronchial asthma (AEBA). Although recent findings suggest that common bacteria are causally associated with AEBA, a comprehensive epidemiologic analysis of infectious pathogens including common/atypical bacteria and viruses in AEBA has not been performed. Accordingly, we attempted to detect pathogens during AEBA by using real-time polymerase chain reaction (PCR) in comparison to conventional methods.

METHODS

We prospectively enroled adult patients with AEBA from August 2012 to March 2014. Infectious pathogens collected in nasopharyngeal swab and sputum samples were examined in each patient by conventional methods and real-time PCR, which can detect 6 bacterial and 11 viral pathogens. The causal association of these pathogens with AEBA severity and their frequency of monthly distribution were also examined.

RESULTS

Among the 64 enroled patients, infectious pathogens were detected in 49 patients (76.6%) using real-time PCR and in 14 patients (21.9%) using conventional methods (p < 0.001). Real-time PCR detected bacteria in 29 patients (45.3%) and respiratory viruses in 28 patients (43.8%). Haemophilus influenzae was the most frequently detected microorganism (26.6%), followed by rhinovirus (15.6%). Influenza virus was the significant pathogen associated with severe AEBA. Moreover, AEBA occurred most frequently during November to January.

CONCLUSIONS

Real-time PCR was more useful than conventional methods to detect infectious pathogens in patients with AEBA. Accurate detection of pathogens with real-time PCR may enable the selection of appropriate anti-bacterial/viral agents as a part of the treatment for AEBA.

Effects of procalcitonin-guided treatment on antibiotic use and need for mechanical ventilation in patients with acute asthma exacerbation: Meta-analysis of randomized controlled trials

OBJECTIVE

The primary outcome was to determine whether serum procalcitonin-guided antibiotic therapy can reduce antibiotic exposure in patients with an acute exacerbation of asthma presenting to the primary care facility or emergency department, or during hospital admission. The secondary outcome was the need for mechanical ventilation.

METHODS

An extensive literature search was performed to identify randomized controlled clinical trials (published in English) that compared serum procalcitonin-guided antibiotic therapy versus antibiotic use according to physician's discretion for adult participants with mild, moderate, or severe acute asthma exacerbations.

RESULTS

Four randomized controlled trials evaluating 457 patients were included in this meta-analysis, with significant homogeneity observed among these studies. Procalcitonin-based protocols decreased antibiotic prescriptions (relative risk 0.58, 95% confidence interval 0.50-0.67). The conclusion regarding the difference between the two groups in the need for mechanical ventilation (relative risk 1.10, 95% confidence interval 0.62-1.94) was guarded due to inadequate power and the potential for type II error. The overall quality of evidence was also limited by the lack of double-blinding.

CONCLUSIONS

These data suggest a potential benefit for the use of serum procalcitonin in guiding antibiotic therapy in patients with an acute asthma exacerbation and advocates the need for more randomized controlled trials.

Treatment of preschool children presenting to the emergency department with wheeze with azithromycin: A placebo-controlled randomized trial

Background

Antibiotics are frequently used to treat wheezing children. Macrolides may be effective in treating bronchiolitis and asthma.

Method

We completed a prospective, double-blinded, randomized placebo-control trial of azithromycin among pre-school children (12 to 60 months of age) presenting to the emergency department with wheeze. Patients were randomized to receive either five days of azithromycin or placebo. Primary outcome was time to resolution of respiratory symptoms after treatment initiation. Secondary outcomes included the number of days children used a Short-Acting Beta-Agonists during the 21 day follow-up and time to disease exacerbation during the following six months (unscheduled health care visit or treatment with an oral corticosteroid for acute respiratory symptoms).

Results

Of the 300 wheezing children recruited, 222 and 169 were analyzed for the primary and secondary outcomes, respectively. The treatment groups had similar demographics and clinical parameters at baseline. Median time to resolution of respiratory symptoms was four days for both treatment arms (interquartile range (IQR) 3,6; p = 0.28). Median number of days of Short-Acting Beta-Agonist use among those who received azithromycin was four and a half days (IQR 2, 7) and five days (IQR 2, 9; p = 0.22) among those who received placebo. Participants who received azithromycin had a 0.91 hazard ratio for time to six-month exacerbation compared to placebo (95% CI 0.61, 1.36, p = 0.65). A pre-determined subgroup analysis showed no differences in outcomes for children with their first or repeat episode of wheezing. There was no significant difference in the proportion of participants experiencing an adverse event.

Conclusion

Azithromycin neither reduced duration of respiratory symptoms nor time to respiratory exacerbation in the following six months after treatment among wheezing preschool children presenting to an emergency department. There was no significant effect among children with either first-time or prior wheezing.

Budesonide + formoterol delivered via Spiromax® for the management of asthma and COPD: The potential impact on unscheduled healthcare costs of improving inhalation technique compared with Turbuhaler®

BACKGROUND

Fixed-dose combinations of inhaled corticosteroids and long-acting β₂ agonists are commonly used for the treatment of asthma and COPD. However, the most frequently prescribed dry powder inhaler delivering this medicine - Symbicort^® (budesonide and formoterol, BF) Turbuhaler^® - is associated with poor inhalation technique, which can lead to poor disease control and high disease management costs. A recent study showed that patients make fewer inhaler errors when using the novel DuoResp^® (BF) Spiromax^® inhaler, compared with BF Turbuhaler^®. Therefore switching patients from BF Turbuhaler^® to BF Spiromax^® could improve inhalation technique, and potentially lead to better disease control and healthcare cost savings.

METHODS

A model was developed to estimate the budget impact of reducing poor inhalation technique by switching asthma and COPD patients from BF Turbuhaler^® to BF Spiromax^® over three years in Germany, Italy, Sweden and the UK. The model estimated changes to the number, and associated cost, of unscheduled healthcare events. The model considered two scenarios: in Scenario 1, all patients were immediately switched from BF Turbuhaler^® to BF Spiromax^®; in Scenario 2, 4%, 8% and 12% of patients were switched in years 1, 2 and 3 of the model, respectively.

RESULTS

In Scenario 1, per patient cost savings amounted to €60.10, €49.67, €94.14 and €38.20 in Germany, Italy, Sweden and the UK, respectively. Total cost savings in each country were €100.86 million, €19.42 million, €36.65 million and €15.44 million over three years, respectively, with an estimated 597,754, 151,480, 228,986 and 122,368 healthcare events avoided. In Scenario 2, cost savings totalled €8.07 million, €1.55 million, €2.93 million and €1.23 million over three years, respectively, with 47,850, 12,118, 18,319, and 9789 healthcare events avoided. Savings per patient were €4.81, €3.97, €7.53 and €3.06.

CONCLUSIONS

We demonstrated that reductions in poor inhalation technique by switching patients from BF Turbuhaler^® to BF Spiromax^® are likely to improve patients' disease control and generate considerable cost savings through healthcare events avoided.

Addressing unmet needs in understanding asthma mechanisms: From the European Asthma Research and Innovation Partnership (EARIP) Work Package (WP)2 collaborators

Asthma is a heterogeneous, complex disease with clinical phenotypes that incorporate persistent symptoms and acute exacerbations. It affects many millions of Europeans throughout their education and working lives and puts a heavy cost on European productivity. There is a wide spectrum of disease severity and control. Therapeutic advances have been slow despite greater understanding of basic mechanisms and the lack of satisfactory preventative and disease modifying management for asthma constitutes a significant unmet clinical need. Preventing, treating and ultimately curing asthma requires co-ordinated research and innovation across Europe. The European Asthma Research and Innovation Partnership (EARIP) is an FP7-funded programme which has taken a co-ordinated and integrated approach to analysing the future of asthma research and development. This report aims to identify the mechanistic areas in which investment is required to bring about significant improvements in asthma outcomes.

Airway and serum biochemical correlates of refractory neutrophilic asthma

Background

Despite progress in the diagnosis and management of asthma, many patients have poorly controlled or refractory asthma (RA). The mechanism of this RA is not well understood.

Objective

We sought to explore the relationship between neutrophils and other biomarkers of RA.

Method

Sixty patients with RA, 30 patients with nonrefractory asthma (NRA), and 20 healthy subjects were enrolled. We performed a comprehensive characterization of these study subjects, which included laboratory and pulmonary function studies, chest computed tomography, and bronchoscopy with bronchoalveolar lavage (BAL). We analyzed BAL fluid and serum for a total of 244 biomolecules using a multiplex assay and correlated them with clinical and other laboratory parameters.

Results

RA was significantly different from NRA with regard to pulmonary function indices, bronchial basement membrane thickness, and BAL fluid neutrophil and lymphocyte counts but not eosinophil counts. BAL fluid neutrophil counts negatively and positively correlated with forced vital capacity and age, respectively. Of the 244 biomolecules studied, 52 and 14 biomolecules from BAL fluid and serum, respectively, were significantly different among the study groups. Thirteen of these 52 molecules correlated with BAL fluid neutrophil counts. BAL fluid from 40% of patients with RA was positive for a pathogenic microbe. Infection-negative neutrophilic RA was associated with an increase in levels of select biomarkers of inflammation in the serum, suggesting the presence of systemic inflammation.

Conclusions

RA was associated with increased numbers of neutrophils and proneutrophilic biomolecules in the airways. Subclinical infection was present in 40% of patients with RA, which likely contributed to neutrophilic inflammation. A subgroup of patients with noninfected neutrophilic RA was associated with systemic inflammation.

Azithromycin for Acute Exacerbations of Asthma : The AZALEA Randomized Clinical Trial

IMPORTANCE

Guidelines recommend against antibiotic use to treat asthma attacks. A study with telithromycin reported benefit, but adverse reactions limit its use.

OBJECTIVE

To determine whether azithromycin added to standard care for asthma attacks in adults results in clinical benefit.

DESIGN, SETTING, AND PARTICIPANTS

The Azithromycin Against Placebo in Exacerbations of Asthma (AZALEA) randomized, double-blind, placebo-controlled clinical trial, a United Kingdom-based multicenter study in adults requesting emergency care for acute asthma exacerbations, ran from September 2011 to April 2014. Adults with a history of asthma for more than 6 months were recruited within 48 hours of presentation to medical care with an acute deterioration in asthma control requiring a course of oral and/or systemic corticosteroids.

INTERVENTIONS

Azithromycin 500 mg daily or matched placebo for 3 days.

MAIN OUTCOMES AND MEASURES

The primary outcome was diary card symptom score 10 days after randomization, with a hypothesized treatment effect size of -0.3. Secondary outcomes were diary card symptom score, quality-of-life questionnaires, and lung function changes, all between exacerbation and day 10, and time to a 50% reduction in symptom score.

RESULTS

Of 4582 patients screened at 31 centers, 199 of a planned 380 were randomized within 48 hours of presentation. The major reason for nonrecruitment was receipt of antibiotics (2044 [44.6%] screened patients). Median time from presentation to drug administration was 22 hours (interquartile range, 14-28 hours). Exacerbation characteristics were well balanced across treatment arms and centers. The primary outcome asthma symptom scores were mean (SD), 4.14 (1.38) at exacerbation and 2.09 (1.71) at 10 days for the azithromycin group and 4.18 (1.48) and 2.20 (1.51) for the placebo group, respectively. Using multilevel modeling, there was no significant difference in symptom scores between azithromycin and placebo at day 10 (difference, -0.166; 95% CI, -0.670 to 0.337), nor on any day between exacerbation and day 10. No significant between-group differences were observed in quality-of-life questionnaires or lung function between exacerbation and day 10, or in time to 50% reduction in symptom score.

CONCLUSIONS AND RELEVANCE

In this randomized population, azithromycin treatment resulted in no statistically or clinically significant benefit. For each patient randomized, more than 10 were excluded because they had already received antibiotics.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01444469.

Identification of novel macrolides with antibacterial, anti-inflammatory and type I and III IFN-augmenting activity in airway epithelium

BACKGROUND

Exacerbations of asthma and COPD are triggered by rhinoviruses. Uncontrolled inflammatory pathways, pathogenic bacterial burden and impaired antiviral immunity are thought to be important factors in disease severity and duration. Macrolides including azithromycin are often used to treat the above diseases, but exhibit variable levels of efficacy. Inhaled corticosteroids are also readily used in treatment, but may lack specificity. Ideally, new treatment alternatives should suppress unwanted inflammation, but spare beneficial antiviral immunity.

METHODS

In the present study, we screened 225 novel macrolides and tested them for enhanced antiviral activity against rhinovirus, as well as anti-inflammatory activity and activity against Gram-positive and Gram-negative bacteria. Primary bronchial epithelial cells were grown from 10 asthmatic individuals and the effects of macrolides on rhinovirus replication were also examined. Another 30 structurally similar macrolides were also examined.

RESULTS

The oleandomycin derivative Mac5, compared with azithromycin, showed superior induction (up to 5-fold, EC50 = 5-11 μM) of rhinovirus-induced type I IFNβ, type III IFNλ1 and type III IFNλ2/3 mRNA and the IFN-stimulated genes viperin and MxA, yet had no effect on IL-6 and IL-8 mRNA. Mac5 also suppressed rhinovirus replication at 48 h, proving antiviral activity. Mac5 showed antibacterial activity against Gram-positive Streptococcus pneumoniae; however, it did not have any antibacterial properties compared with azithromycin when used against Gram-negative Escherichia coli (as a model organism) and also the respiratory pathogens Pseudomonas aeruginosa and non-typeable Haemophilus influenzae. Further non-toxic Mac5 derivatives were identified with various anti-inflammatory, antiviral and antibacterial activities.

CONCLUSIONS

The data support the idea that macrolides have antiviral properties through a mechanism that is yet to be ascertained. We also provide evidence that macrolides can be developed with anti-inflammatory, antibacterial and antiviral activity and show surprising versatility depending on the clinical need.

The economic burden of asthma and chronic obstructive pulmonary disease and the impact of poor inhalation technique with commonly prescribed dry powder inhalers in three European countries

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) are common chronic inflammatory respiratory diseases, which impose a substantial burden on healthcare systems and society. Fixed-dose combinations (FDCs) of inhaled corticosteroids (ICS) and long-acting β2 agonists (LABA), often administered using dry powder inhalers (DPIs), are frequently prescribed to control persistent asthma and COPD. Use of DPIs has been associated with poor inhalation technique, which can lead to increased healthcare resource use and costs.

METHODS

A model was developed to estimate the healthcare resource use and costs associated with asthma and COPD management in people using commonly prescribed DPIs (budesonide + formoterol Turbuhaler(®) or fluticasone + salmeterol Accuhaler(®)) over 1 year in Spain, Sweden and the United Kingdom (UK). The model considered direct costs (inhaler acquisition costs and scheduled and unscheduled healthcare costs), indirect costs (productive days lost), and estimated the contribution of poor inhalation technique to the burden of illness.

RESULTS

The direct cost burden of managing asthma and COPD for people using budesonide + formoterol Turbuhaler(®) or fluticasone + salmeterol Accuhaler(®) in 2015 was estimated at €813 million, €560 million, and €774 million for Spain, Sweden and the UK, respectively. Poor inhalation technique comprised 2.2-7.7 % of direct costs, totalling €105 million across the three countries. When lost productivity costs were included, total expenditure increased to €1.4 billion, €1.7 billion and €3.3 billion in Spain, Sweden and the UK, respectively, with €782 million attributable to poor inhalation technique across the three countries. Sensitivity analyses showed that the model results were most sensitive to changes in the proportion of patients prescribed ICS and LABA FDCs, and least sensitive to differences in the number of antimicrobials and oral corticosteroids prescribed.

CONCLUSIONS

The cost of managing asthma and COPD using commonly prescribed DPIs is considerable. A substantial, and avoidable, contributor to this burden is poor inhalation technique. Measures that can improve inhalation technique with current DPIs, such as easier-to-use inhalers or better patient training, could offer benefits to patients and healthcare providers through improving disease outcomes and lowering costs.

Chronic Infection and Severe Asthma

Chronic bacterial infection is implicated in both the development and severity of asthma. The atypical bacteria Mycoplasma pneumoniae and Chlamydophila pneumoniae have been identified in the airways of asthmatics and correlated with clinical features such as adult onset, exacerbation risks, steroid sensitivity, and symptom control. Asthmatic patients with evidence of bacterial infection may benefit from antibiotic treatment directed towards these atypical organisms. Examination of the airway microbiome may identify microbial communities that confer risk for or protection from severe asthma.

Macrolides for Acute Wheezing Episodes in Preschool Children

The National Asthma Education and Prevention Program's Expert Panel Report 3, Guidelines for the Diagnosis and Management of Asthma does not recommend antibiotics for the management of acute episodes of asthma exacerbation. Macrolides seem to have some potential effect beyond or in addition to their antibacterial effect. It has been reported that macrolides may potentially benefit patients with chronic inflammatory airway diseases due to their antibacterial, antiviral, and/or anti-inflammatory effects. This review presents recent data on use of azithromycin in prevention and management of acute exacerbation of respiratory symptoms in infants and young children.

Azithromycin differentially affects the IL-13-induced expression profile in human bronchial epithelial cells

The T helper 2 (Th2) cytokine interleukin(IL)-13 is a central regulator in goblet cell metaplasia and induces the recently described Th2 gene signature consisting of periostin (POSTN), chloride channel regulator 1 (CLCA1) and serpin B2 (SERPINB2) in airway epithelial cells. This Th2 gene signature has been proposed as a biomarker to classify asthma into Th2-high and Th2-low phenotypes. Clinical studies have shown that the macrolide antibiotic azithromycin reduced clinical symptoms in neutrophilic asthma, but not in the classical Th2-mediated asthma despite the ability of azithromycin to reduce IL-13-induced mucus production. We therefore hypothesize that azithromycin differentially affects the IL-13-induced expression profile. To investigate this, we focus on IL-13-induced mucin and Th2-signature expression in human bronchial epithelial cells and how this combined expression profile is affected by azithromycin treatment. Primary bronchial epithelial cells were differentiated at air liquid interface in presence of IL-13 with or without azithromycin. Azithromycin inhibited IL-13-induced MUC5AC, which was accompanied by inhibition of IL-13-induced CLCA1 and SERPINB2 expression. In contrast, IL-13-induced expression of POSTN was further increased in cells treated with azithromycin. This indicates that azithromycin has a differential effect on the IL-13-induced Th2 gene signature. Furthermore, the ability of azithromycin to decrease IL-13-induced MUC5AC expression may be mediated by a reduction in CLCA1.

Respiratory drugs and macrolides prevent asthma exacerbations: A real-world investigation

OBJECTIVE

We investigated the real-world effectiveness of several drugs (including short- and long-acting beta-agonists [SABAs and LABAs], inhaled corticosteroids [ICS], and antibiotics) in preventing severe asthma exacerbations by carrying-out a large observational study based on the healthcare utilization databases of the Italian Lombardy Region.

METHODS

We identified all patients aged 6-40 years who performed an Emergency Department visit for asthma during 2010-2012 as cases. To address bias due to unmeasured confounders, we implemented a case-crossover (CC) design. Addressing other specific sources of systematic errors (e.g. protopathic bias) was of particular concern in this study.

RESULTS

A total of 7300 cases were included in the study. The CC odds ratios (95% confidence intervals) for current vs. past use were 0.81 (0.71, 0.92) for SABAs, 0.83 (0.72, 0.96) for ICS, 0.78 (0.66, 0.91) for LABA/ICS fixed combinations, 0.79 (0.65, 0.97) for other respiratory drugs, and 0.79 (0.69, 0.92) for macrolides antibiotics. Sensitivity analyses showed that our results were robust with respect to several sources of bias.

CONCLUSIONS

Our study provides evidence from the real-world clinical practice on the effectiveness of several respiratory drugs and macrolides in reducing the risk of severe asthma exacerbations.

Airway Microbiota in Severe Asthma and Relationship to Asthma Severity and Phenotypes

BACKGROUND

The lower airways harbor a community of bacterial species which is altered in asthma.

OBJECTIVES

We examined whether the lower airway microbiota were related to measures of asthma severity.

METHODS

We prospectively recruited 26 severe asthma, 18 non-severe asthma and 12 healthy subjects. DNA was extracted from induced sputum and PCR amplification of the V3-V5 region of bacterial 16S rRNA gene was performed.

RESULTS

We obtained 138,218 high quality sequences which were rarefied at 133 sequences/sample. Twenty OTUs had sequences ≥1% of total. There were marked differences in the distribution of Phyla between groups (P = 2.8x10-118). Bacteroidetes and Fusobacteria were reduced in non-severe and severe asthmatic groups. Proteobacteria were more common in non-severe asthmatics compared to controls (OR = 2.26; 95% CI = 1.94-2.64) and Firmicutes were increased in severe asthmatics compared to controls (OR = 2.15; 95%CI = 1.89-2.45). Streptococcal OTUs amongst the Firmicutes were associated with recent onset asthma, rhinosinusitis and sputum eosinophilia.

CONCLUSIONS

Sputum microbiota in severe asthma differs from healthy controls and non-severe asthmatics, and is characterized by the presence of Streptococcus spp with eosinophilia. Whether these organisms are causative for the pathophysiology of asthma remains to be determined.

The Belgian trial with azithromycin for acute COPD exacerbations requiring hospitalization: an investigator-initiated study protocol for a multicenter, randomized, double-blind, placebo-controlled trial

Background

Long-term use of macrolide antibiotics is effective to prevent exacerbations in chronic obstructive pulmonary disease (COPD). As risks and side effects of long-term intervention outweigh the benefits in the general COPD population, the optimal dose, duration of treatment, and target population are yet to be defined. Hospitalization for an acute exacerbation (AE) of COPD may offer a targeted risk group and an obvious risk period for studying macrolide interventions.

Methods/design

Patients with COPD, hospitalized for an AE, who have a smoking history of ≥10 pack-years and had ≥1 exacerbation in the previous year will be enrolled in a multicenter, randomized, double-blind, placebo-controlled trial (NCT02135354). On top of a standardized treatment of systemic corticosteroids and antibiotics, subjects will be randomized to receive either azithromycin or placebo during 3 months, at an uploading dose of 500 mg once a day for 3 days, followed by a maintenance dose of 250 mg once every 2 days. The primary endpoint is the time-to-treatment failure during the treatment phase (ie, from the moment of randomization until the end of intervention). Treatment failure is a novel composite endpoint defined as either death, the admission to intensive care or the requirement of additional systemic steroids or new antibiotics for respiratory reasons, or the diagnosis of a new AE after discharge.

Discussion

We investigate whether azithromycin initiated at the onset of a severe exacerbation, with a limited duration and at a low dose, might be effective and safe in the highest risk period during and immediately after the acute event. If proven effective and safe, this targeted approach may improve the treatment of severe AEs and redirect the preventive use of azithromycin in COPD to a temporary intervention in the subgroup with the highest unmet needs.

The clinical management of lower respiratory tract infections

The 2010 Global Burden of Disease Study reported that lower respiratory tract infections, including pneumonia, are the fourth most common cause of death globally. The etiology of acute bronchitis and asthma exacerbations is mostly viral and the therapy is symptomatic. Management decisions in community acquired pneumonia regarding site of care, extent of assessment, and level of treatment are based primarily on disease severity (outpatient, inpatient, ICU admission). Antibiotics are the main choice of treatment for patients with pneumonia, acute exacerbations (AE) of COPD (including increased sputum purulence and worsening shortness of breath) and AE of non-CF bronchiectasis. Inhaled antibiotics may represent a more optimal approach for the treatment and prevention of AE of non-CF bronchiectasis. Approved strategies for the prevention of exacerbations include smoking cessation and rehabilitation programs, drug therapy and vaccination.

Systematic Review and Meta-Analysis: Macrolides- and Amoxicillin/Clavulanate-induced Acute Liver Injury

Antibacterials are frequently associated with idiosyncratic drug-induced liver injury (DILI). The objective of this study was to estimate the risk of macrolides and amoxicillin/clavulanate (AMC) on DILI. We conducted a systematic review (SR) and meta-analysis (MA) with studies retrieved from PubMed, Cochrane Library Plus, Web of Knowledge, clinicaltrials.gov, Livertox and Toxline (1980-2014). We searched for macrolides, AMC and MeSH and synonym terms for DILI. We included all study designs except case reports/series, all population ages and studies with a placebo/non-user comparator. We summarized the evidence with a random-effects MA. Quality of the studies was appraised with a checklist developed for SR of adverse effects. Heterogeneity and publication bias were assessed with different exploratory tools. We finally included 10 (two randomized clinical trials, six case-control, one cohort and one case-population studies) and 9 (case-population excluded) articles in the SR and MA, respectively. The overall summary relative risk of DILI for macrolides was 2.85 [95% confidence interval (CI) 1.81-4.47], p < 0.0001, I(2) = 57%. Three studies were perceived to be missing in the area of low statistical significance. Year of study and selected exposure window partly explained the variability between studies. For AMC, the risk of DILI was 9.38 (95% CI 0.65-135.41) p = 0.3, I2 = 95%. In conclusion, although spontaneous reports and case series have long established an association between macrolides and AMC with acute liver injury, these SR and MA have assessed the magnitude of this association. The low incidence of DILI and the therapeutic place of these antibiotics might tilt the balance in favour of their benefits.

Infections and Asthma

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Wheezing viral respiratory illnesses are the most common initial presentation of childhood asthma.

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Once asthma is established, viral infections, most notably rhinovirus (RV), are the most frequent trigger of severe asthma exacerbations. RV-C appears to be a particularly pathogenic virus in children with asthma.

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Evidence has recently emerged to suggest that bacterial pathogens in the lower airway may contribute to the expression of asthma. Ongoing studies are critical to our understanding of the role of the airway microbiome in asthma inception and exacerbation.

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Synergistic interactions between underlying allergy and virus infections play an important mechanistic role in asthma inception and exacerbation, and are an important therapeutic target.

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Novel therapies are needed to prevent and treat virus-induced wheezing and asthma exacerbations.

Azithromycin for episodes with asthma-like symptoms in young children aged 1-3 years: a randomised, double-blind, placebo-controlled trial

Background

Bacteria and viruses are equally associated with the risk of acute episodes of asthma-like symptoms in young children, suggesting antibiotics as a potential treatment for such episodes. We aimed to assess the effect of azithromycin on the duration of respiratory episodes in young children with recurrent asthma-like symptoms, hypothesising that it reduces the duration of the symptomatic period.

Methods

In this randomised, double-blind, placebo-controlled trial, we recruited children aged 1–3 years, who were diagnosed with recurrent asthma-like symptoms from the Copenhagen Prospective Studies on Asthma in Childhood 2010 cohort; a birth cohort consisting of the general Danish population of Zealand, including Copenhagen. Exclusion criteria were macrolide allergy, heart, liver, neurological, and kidney disease, and, before each treatment, one or more clinical signs of pneumonia (respiratory frequency of ≥50 breaths per min; fever of ≥39°C; C-reactive protein concentration of ≥476·20 nmol/L [≥50 mg/L]). Each episode of asthma-like symptoms lasting at least 3 days was randomly allocated to a 3-day course of azithromycin oral solution of 10 mg/kg per day or placebo after thorough examination by a study physician at the Copenhagen Prospective Studies on Asthma research unit. Each episode was randomly allocated independently of previous treatment from a computer-generated list of random numbers in blocks of ten (generated at the Pharmacy of Glostrup). Investigators and children were masked until the youngest child turned 3 years of age and throughout the data validation and analysis phases. The primary outcome was duration of the respiratory episode after treatment, verified by prospective daily diaries and analysed with Poisson regression. Analyses were per protocol (excluding those without a primary outcome measure or who did not receive treatment). This trial is registered with ClinicalTrials.gov, number NCT01233297.

Findings

Between Nov 17, 2010, and Jan 28, 2014, we randomly allocated 158 asthma-like episodes in 72 children (79 [50%] to azithromycin and 79 [50%] to placebo). The mean duration of the episode after treatment was 3·4 days for children receiving azithromycin compared with 7·7 days for children receiving placebo. Azithromycin caused a significant shortening of the episode of 63·3% (95% CI 56·0–69·3; p<0·0001). The effect size increased with early initiation of treatment, showing a reduction in episode duration of 83% if treatment was initiated before day 6 of the episode compared with 36% if initiated on or after day 6 (p<0·0001). We noted no differences in clinical adverse events between the azithromycin (18 [23%] of 78 episodes included in final analysis) and placebo (24 [30%] of 79) groups (p=0·30), but we did not investigate bacterial resistance patterns after treatment.

Interpretation

Azithromycin reduced the duration of episodes of asthma-like symptoms in young children, suggesting that this drug could have a role in acute management of exacerbations. Further research is needed to disentangle the inflammatory versus antimicrobial aspects of this relation.

Funding

Lundbeck Foundation, Danish Ministry of Health, Danish Council for Strategic Research, Capital Region Research Foundation.