A Systematic Review and Meta-Analysis of the Prevalence and Impact of Pulmonary Bacterial Colonisation in Stable State Chronic Obstructive Pulmonary Disease (COPD)

Abstract

Background: Half of acute exacerbations of COPD are due to bacterial infection, and the other half are likely influenced by microbial colonisation. The same organisms commonly cultured during acute exacerbations are often found in the sputum of patients during stability. A robust assessment of the prevalence of potentially pathogenic microorganisms (PPMs) in the sputum of stable COPD patients may help to inform the targeted prevention of exacerbation by these organisms. Methods: A systematic review and meta-analysis was carried out to determine the prevalence of PPMs in patients with COPD in the stable state. Meta-analysis of prevalence was carried out using the Freeman–Tukey double arcsine transformation random effects model, and sub-group analysis was performed for sputum modality. Prevalence of total and individual PPMs was calculated from patient-level data from individual studies. Results: Pooled prevalence of PPMs identified by sputum culture was found to be 41% (95% CI 36–47%). Significant heterogeneity was found across all studies, which can likely be attributed to inconsistent measuring and reporting of PPMs. The most commonly reported organisms were H. influenzae, M catarrhalis, S. pneumoniae, S. aureus, and P. aeruginosa. Declining lung function was weakly correlated with prevalence of PPMs. Conclusion: The airways of patients with COPD are colonised with PPMs during the stable state in almost half of patients. A complex relationship likely exists between the microbiome in the stable state and the phenotype of COPD patients. Targeted microbial therapy for preventing exacerbations of COPD should carefully consider the stable microbiome as well as the exacerbated.

Chronic Obstructive Pulmonary Disease: The Present and Future

“…Monitoring markers of oxidative stress and miR genotyping for precision-based chemotherapy [10] Iron-deficient COPD IV iron replacement Monitoring hepcidin as a marker for non-anaemic iron deficiency [23] Antimicrobial-resistant COPD Targeted antibiotics based on culture sensitivities Use of colour charts to determine commencement of antibiotics [14] Key-LABA: long-acting β-agonists; LAMA: long-acting muscarinic antagonists; ICS: inhaled corticosteroids; HRQoL: health-related quality of life; CFTR: cystic fibrosis transmembrane receptor; miR: microRNA; VTE: venous thromboembolism; NIV: noninvasive ventilation; OSA/ORRF: obstructive sleep apnoea/obesity-related respiratory failure; COPD: chronic obstructive pulmonary disease; IV: intravenous.…”

“…A systematic review by Armitage et al clarifies the prevalence of colonisation in stable-state COPD and identifies its relationship to the modality of sample collection [ 14 ]. The authors systematically identified 36 studies, which included a total of over 3000 patients, to perform a meta-analysis, identifying H. influenzae as the most prevalent PPM, colonising 41% of samples regardless of sampling method.…”

Bacterial Species and Inflammatory Cell Variability in Respiratory Tracts of Patients with Chronic Obstructive Pulmonary Disease Exacerbation: A Multicentric Study

“…The most commonly isolated microbes are H. influenzae, M. catarrhalis, S. pneumoniae, S. aureus, and P. aeruginosa . 3 …”

“…The most commonly isolated microbes are H. influenzae, M. catarrhalis, S. pneumoniae, S. aureus, and P. aeruginosa. 3 Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is an acute and sustained worsening of a patient's condition from a stable state. 4 Possible risk factors include air pollution, seasonal change, ethnic background, associated comorbidities, poor exercise capacity and obesity.…”

The Impact of Chronic Bronchial Infection in COPD: A Proposal for Management

“…Chronic bronchial infection is frequent in patients with moderate to severe COPD; up to 50% of patients may carry PPMs in their bronchial tree during stable state. 37 , 68 The persistence of PPMs in the lungs of patients with COPD may be defined as a CBI due to its impact on symptoms, exacerbations, and the natural history of the disease. 38 Due to its deleterious effects, CBI should be considered a treatable trait of COPD.…”