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

"The effect of 48-weeks azithromycin therapy on levels of soluble biomarkers associated with HIV-associated chronic lung disease"

OBJECTIVES

HIV-associated immune activation contributes to chronic lung disease (CLD) in children and adolescents living with HIV. Azithromycin has immunomodulatory and anti-microbial properties that may be useful for treating HIV-associated CLD (HCLD). This study describes the effect of azithromycin on expression of plasma soluble biomarkers in children and adolescents with HCLD.

METHODS

This study was nested within a multi-site double-blind, placebo controlled, randomised controlled trial (RCT) of azithromycin in individuals aged 6-19 years with HCLD (defined as FEV1 z-score < -1) in Malawi and Zimbabwe (BREATHE (NCT02426112)). Participants were randomized 1:1 to once-weekly oral azithromycin with weight-based dosing, for 48 weeks, or placebo. Twenty-six plasma soluble biomarkers were measured on a MagPix Luminex instrument at enrolment, after 48-weeks of treatment and 24-weeks after treatment cessation. Mixed effects models were constructed to compare biomarker expression across treatment and placebo groups.

RESULTS

Weekly azithromycin was associated with reduced levels of C-Reactive Protein (CRP), E-Selectin, Matrix metalloproteinase 10 (MMP-10). Treatment effects for all soluble biomarkers were not sustained 24-weeks after treatment cessation with biomarker expression returning to pre-treatment levels.

CONCLUSIONS

We observed real-world effects of azithromycin on acute inflammation, neutrophil accumulation, and extracellular matrix degradation, that were not sustained after treatment cessation. These results are pertinent when using azithromycin for its immunomodulatory properties, or targeting pathways represented by the soluble biomarkers in this study.

Azithromycin attenuates wheezing after pulmonary inflammation through inhibiting histone H3K27me3 hypermethylation mediated by EZH2

BACKGROUND

Histone methylation modification plays an irreplaceable role in the wheezing diseases. The aim of this study was to explore whether azithromycin (AZM) attenuates post-inflammatory wheezing through inhibiting hypermethylation of histone H3K27me3 mediated by EZH2.

RESULTS

A randomized controlled trial was conducted on 227 children who underwent fiber-optic bronchoscopy, and bronchoalveolar lavage fluid (BALF) was collected for analyses. The expressions of IL-6, IL-2, NF-κB P65, EZH2 and H3K27me3 in the BALF of wheezing cases were significantly increased when compared with levels in non-wheezing cases (P < 0.05), while IL-10 was decreased (P < 0.05). AZM attenuated the overexpression of NF-κB P65, EZH2 and H3K27me3 in wheezing cases (P < 0.05) and shortened the time of wheezing in wheezing cases (P < 0.05). An in vitro model of inflammation was established using rat alveolar macrophages induced by lipopolysaccharide (LPS). AZM, SN50 (a NK-κB inhibitor) and GSK126 (an EZH2 inhibitor) attenuated the overexpression of EZH2, NF-κB P65 and H3K27me3 induced by LPS in rat alveolar macrophages (P < 0.05). AZM, SN50 and GSK126 normalized the decreased expression of IL-10 induced by LPS in the same samples (P < 0.05). Co-immunoprecipitation results showed that H3K27me3 interacted with EZH2 and NF-κB P65, and immunofluorescence data showed that AZM and SN50 inhibited LPS-induced NF-κB P65 nuclear translocation in rat alveolar macrophages.

CONCLUSION

Histone H3K27me3 hypermethylation mediated by EZH2 may be involved in wheezing after pulmonary inflammation. AZM attenuated wheezing after pulmonary inflammation by inhibiting NF-κB P65-related hypermethylation of H3K27me3 mediated by EZH2.

Azithromycin for Poorly Controlled Asthma in Children: A Randomized Controlled Trial

BACKGROUND

Azithromycin has immunomodulatory actions, and its beneficial effects have been demonstrated in asthmatic adults. Data on children are limited.

RESEARCH QUESTION

Does the addition of oral azithromycin to standard therapy in children with poorly controlled asthma improve asthma control compared with standard treatment alone?

STUDY DESIGN AND METHODS

This open-label randomized controlled trial included children (5-15 years of age) with poorly controlled asthma defined by Asthma Control Test (ACT) and Childhood Asthma Control Test (CACT) score of ≤ 19. They were randomized to receive azithromycin (10 mg/kg) three times weekly for 3 months along with standard treatment or standard treatment alone. The primary outcome was the ACT and CACT scores at 3 months. Secondary outcomes were asthma control according to Global Initiative for Asthma (GINA) guidelines, the number of exacerbations, change in spirometry parameters, change in fractional exhaled nitric oxide (Feno) level, positive throat swab results, and side effects.

RESULTS

The trial included 120 children (89 boys; 60 in each group). The mean ± SD age was 9.9 ± 3 years. The baseline parameters were similar between the groups. Mean ± SD ACT and CACT scores (available for 115 children) at 3 months of intervention were 21.71 ± 2.17 vs 18.33 ± 2.19 (P < .001) in the azithromycin and control groups, respectively. The numbers of children with well-controlled asthma according to GINA guidelines were 41 of 56 vs 10 of 56 in the azithromycin and control groups, respectively (P < .001). The median number of exacerbations requiring emergency visit and steroid use were fewer in the azithromycin group: 0 (interquartile range [IQR], 3) vs 1 [IQR, 6]; P < .001). No difference was found in Feno level, spirometry parameters, positive throat swab results, and adverse effects between the groups.

INTERPRETATION

The use of azithromycin in children with poorly controlled asthma resulted in improved asthma control and reduced exacerbations.

TRIAL REGISTRY

Clinical Trials Registry - India; No.: CTRI/2019/06/019727; URL: www.ctri.nic.in.

Use of the pleth variability index in children with obstructive respiratory disease

INTRODUCTION

The phenomenon of pulsus paradoxus (PP) develops at varying rates in relation to the severity of the disease in obstructive respiratory tract disease. The Pleth Variability Index (PVI) is the measurement value of perfusion index changes that occur with ventilation, which are determined during at least one respiratory cycle. Therefore, noninvasive measurement of PVI can help in the measurement of PP. The current study aims to determine the role of PVI measurements before and after bronchodilator therapy during admission to the hospital in children with obstructive respiratory tract disease.

METHODS

Age, gender, Pulmonary Index Score (PIS), and PVI data of patients aged 2-18 years who applied to the pediatric emergency department with signs of obstructive respiratory tract disease were recorded in triage. The PVI and PIS scores of the patients, who were divided into three groups according to their clinical severity scores, were recorded before and after bronchodilator treatment, and they were compared to the PVI values according to the disposition results.

RESULTS

A total of 133 patients were included in this prospective, single-center study. The PVI values before and after treatment were significantly higher in patients with severe disease compared to the mild and moderate groups (p < 0.001). Post-treatment PVI values were significantly lower than pre-treatment values in all clinical severity groups (p < 0.001). While a total of 95 (71.43%) patients were discharged from the emergency department, 31 (23.31%) patients were admitted to the relevant department, and seven (5.26%) patients were admitted to the pediatric intensive care unit. The PVI values before and after treatment were significantly higher in the hospitalized group compared to the group discharged from the emergency department (p < 0.001). The areas under the ROCs were 0.940, 0.865, and 0.843 for the PVI measurements in patients with severe disease, moderate disease, and hospitalization (p< 0.001).

CONCLUSIONS

Automated PVI measurement can be used as a noninvasive, rapid, and objective tool in the emergency department triage of patients admitted to the pediatric emergency department with signs of asthma attack or reactive respiratory tract disease.

The efficacy and safety of azithromycin in treatment for childhood asthma: A systematic review and meta-analysis

BACKGROUND

Azithromycin (AZI) is increasingly used for childhood asthma despite limited and inconsistent data. We aimed to evaluate the efficacy and safety of AZI in childhood asthma.

METHODS

We searched seven databases to include randomized controlled trials (RCTs) of AZI in the treatment of childhood asthma. Four reviewers independently screened the records. Risk of Bias 2 was used to assess the quality of RCTs. Risk ratios with 95% confidence interval (CI) from dichotomous outcomes, and mean difference (MD) with 95% CI from continuous outcomes were pooled.

RESULTS

We included 19 eligible reports from 17 studies. The prevalence of exacerbations in AZI + budesonide (BUD) + β₂ agonist (BA) group was lower than BUD + BA group (four [13%] vs. 19 [63%], p < 0.05) in 6- 14 years old children with chronic persistent asthma. AZI plus antiasthma drugs (AADs) could improve the posttreatment childhood asthma control test score (MD = 2.97; 95% CI, 2.39-3.54) compared to AADs alone in children with chronic persistent asthma. AZI plus AADs could improve posttreatment forced expiratory volume in 1 s of predicted value/forced vital capacity % (MD = 10.24%; 95% CI, 6.44%-14.03%) and posttreatment peak expiratory flow % of predicted value (MD = 7.00%; 95% CI, 2.53%-11.47%) compared to AADs alone in children with chronic persistent asthma. The most common adverse reactions of AZI combined with other drugs were gastrointestinal reactions.

CONCLUSIONS

AZI may be beneficial in improving some clinical symptoms and lung functions in older asthma children (over 6 years old) with persistent asthma. But it still requires further research.

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

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

How does one choose the appropriate pharmacotherapy for children with lower respiratory tract infections?

INTRODUCTION

The definition of acute lower respiratory tract infection (LRTI) includes any infection involving the respiratory tract below the level of the larynx. In children, the most common acute LRTIs, and those with the greatest clinical relevance, are community-acquired pneumonia (CAP), bronchiolitis, bronchitis and tuberculosis (TB). The clinical relevance of LRTIs implies that they must be addressed with the most effective therapy. Antibiotics and antivirals play an essential role in this regard.

AREAS COVERED

In this paper, the most recent advances in the drug treatment of LRTIs in children are discussed.

EXPERT OPINION

Although LRTIs are extremely common and one of the most important causes of hospitalization and death in children, anti-infective therapy for these diseases remains unsatisfactory. For CAP and BR, the most important problem is the overuse and misuse of antibiotics; for BCL, the lack of drugs with demonstrated efficacy, safety and tolerability; for TB, the poor knowledge on the true efficacy and safety of the new drugs specifically planned to overcome the problem of MDR M. tuberculosis strains. There is still a long way to go for the therapy of pediatric LRTIs to be considered satisfactory.

Efficacy of Macrolides on Acute Asthma or Wheezing Exacerbations in Children with Recurrent Wheezing: A Systematic Review and Meta-analysis

INTRODUCTION

The role of macrolides for treatment of children with acute asthma or wheezing exacerbations is unclear.

OBJECTIVE

The aim of this systematic review was to evaluate the effectiveness of macrolides in children with recurrent wheezing presenting with acute asthma or wheezing exacerbation.

METHODS

We conducted an electronic search in MEDLINE, EMBASE, CINAHL, LILACS, CENTRAL, and ClinicalTrials.gov.

STUDY SELECTION CRITERIA

Randomized controlled trials of macrolides (any macrolide) compared with placebo or standard treatment in children up to 18 years with recurrent wheezing/asthma presenting with an acute exacerbation.

OUTCOMES

Primary outcomes were need for hospitalization and/or time of acute asthma/wheezing symptoms resolution; secondary outcomes were duration of stay in the emergency department (ED)/clinic, severity of symptoms of the index episode, use of additional systemic corticosteroids or short active β-2 agonists, changes in lung function measures, ED visit/hospitalization during first week after index episode, time to next exacerbation, or adverse effects (AEs).

RESULTS

Only three studies met the inclusion criteria (n = 334 children, 410 treated episodes); two studies included recurrent wheezers and the third included asthmatic children. There was no difference in hospitalization between groups, but children treated with macrolides had a significantly lower time to symptoms resolution than controls, although the magnitude of benefit remains to be quantified due to no normal distribution data presented. There was no difference in time to next episode of exacerbation (HR 0.96; 95% CI 0.71-1.28; I² = 0%; p = 0.77). In one study, children receiving macrolides had a significant decrease in the severity of symptoms, decrease use of salbutamol, and another study showed improved lung function. No study evaluated antibiotic resistance development.

CONCLUSIONS

Limited evidence support that a macrolide trial could be considered in children with acute asthma or recurrent wheezing exacerbation.

Tacrolimus reduces atherosclerotic plaque formation in ApoE-/- mice by inhibiting NLRP3 inflammatory corpuscles

Effect of tacrolimus on atherosclerotic plaques and its influence on Nod-like receptor protein 3 (NLRP3) inflammatory pathway were studied by establishing the mouse model of atherosclerosis. The mice were divided into 3 groups: C57BL/6 mouse group (WT group), ApoE^-/- mouse group (ApoE^-/- group) and ApoE^-/- mouse + tacrolimus intervention group (ApoE^-/- + Tac group). The area of atherosclerotic plaques and the pathological morphologic changes were observed. The NLRP3, interleukin-1β (IL-1β), IL-18, NLRP3 inflammatory corpuscles, pro-inflammatory factors IL-1β and IL-18 in the aorta were analyzed. The area of atherosclerotic plaques in ApoE^-/- mice was increased significantly, and it was significantly reduced after tacrolimus intervention. After tacrolimus intervention, the arterial intima became obviously thinner and no obvious cholesterol crystals were observed. The macrophage infiltration in atherosclerotic plaques was significantly increased, and the content of smooth muscle cells was also increased. The levels of serum IL-1β, IL-18 and NLRP3 in ApoE^-/- mice were significantly increased, and they remarkably declined after tacrolimus intervention. ROS content in atherosclerotic plaques was increased in ApoE^-/- mice, and it remarkably declined after tacrolimus intervention. The protein content of NLRP3, ASC, Casp-1, IL-1β and IL-18 in the aorta in ApoE^-/- mice was remarkably increased, and they were inhibited to some extent after tacrolimus intervention. In conclusion, it is speculated that tacrolimus may reduce the formation of AS through inhibiting ROS in macrophages and activation of NLRP3 inflammatory corpuscles and reducing the release of IL-1β and IL-18.

Double Aortic Arch Mimics the Clinical Characteristics of Severe Reactive Airway Disease in a Pediatric Patient

Reactive airway disease is a prevalent condition that can be detected in the early infancy period. The condition might also deteriorate into asthma in some cases. If infants do not respond to the treatment of persistent wheeze and coughing, other rare causes should be investigated. The complete form of vascular ring is an extremely uncommon congenital cardiovascular abnormality. Double aortic arch constitutes the most significant portion of the complete vascular ring anomalies. Clinical manifestations of the anomaly are mainly respiratory due to the tracheal compression and mimicking the conditions of asthma. There have not been many reports about the clinical presentations of double aortic arch being remarkably similar to the same clinical manifestations of asthma in the literature. As far as we can be sure, there have not been any reported cases about severe reactive airway disease that caused a patient to have a life-threatening condition in the pediatric intensive care unit. Herein, we present a 5-month-old girl who had double aortic arch. Her anatomical aberration was diagnosed by three-dimensional computed tomography angiography of thorax, and the anomaly mimicked the clinical characteristics of life-threatening severe reactive airway disease.

Effect of pidotimod combined with azithromycin on children with mycoplasma pneumonia and the expression levels of IL-10 and G-CSF in serum

This study explored the effect of pidotimod combined with azithromycin on children with mycoplasma pneumonia and the expression of interleukin-10 (IL-10) and granulocyte colony-stimulating factor (G-CSF) in serum. The clinical data of 149 children with mycoplasma pneumonia from May 2014 to May 2018 in Zhangqiu District Maternal and Child Health Care Hospital were collected. Among them, 70 children treated with azithromycin sequential therapy were the control group, and 79 children treated with the combination of pidotimod and azithromycin were the observation group. Double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was used to determine the expression levels of IL-10 and G-CSF in serum before and after treatment. Pearson's correlation coefficient was used to analyze the correlation between IL-10 and G-CSF in serum. The total effective rate in the observation group (94.94%) was significantly higher than that in the control group (81.43%) (P<0.05). There was no significant difference in the expression levels of IL-10 and G-CSF between the two groups before treatment (P>0.05). The expression levels of IL-10 and G-CSF in the two groups after treatment were significantly lower than those before treatment (P<0.05). After treatment, the expression levels of IL-10 and G-CSF in serum in the observation group were significantly lower than those in the control group. There was a significant positive correlation between the expression levels of IL-10 and G-CSF before and after treatment in the observation group (P<0.05), and a significant positive correlation between the expression levels of IL-10 and G-CSF before and after treatment in the control group (P<0.05). Compared with sequential treatment with azithromycin alone, pidotimod combined with azithromycin significantly reduced the expression levels of IL-10 and G-CSF in serum of children with mycoplasma pneumonia, improved the curative effect and reduced the occurrence of adverse reactions, which has high application value in clinic.