The airway microbiome in COPD, bronchiectasis and bronchiectasis-COPD overlap

Area of Science:

• Respiratory Medicine
• Microbiology
• Genomics

Background:

• The airway microbiome plays a crucial role in respiratory health and disease.
• Understanding microbial shifts in chronic respiratory conditions like COPD and bronchiectasis is vital for effective management.
• The bronchiectasis-COPD overlap (BCO) presents a unique clinical challenge with an understudied microbiome.

Purpose of the Study:

• To review and synthesize current knowledge on the airway microbiome in COPD, bronchiectasis, and BCO.
• To identify key microbial players and their association with disease severity, exacerbations, and outcomes.
• To highlight the impact of advanced sequencing technologies on understanding respiratory microbiomes.

Main Methods:

• Comprehensive literature search across major scientific databases (PubMed, Google Scholar, EMBASE, Web of Science).
• Inclusion of studies focusing on human airway microbiomes in COPD, bronchiectasis, and BCO, published in English.
• Utilized search terms encompassing disease names and microbiome-related keywords (microbiome, mycobiome, metagenomics).

Main Results:

• Airway microbiome composition in COPD and bronchiectasis is comparable, dominated by Proteobacteria, Firmicutes, and Bacteroidetes.
• Microbiome alterations correlate with disease severity and exacerbations in both COPD and bronchiectasis.
• Specific microbial profiles (e.g., Haemophilus in COPD, Pseudomonas in bronchiectasis, Aspergillus in mycobiomes) are linked to poorer survival, increased exacerbations, and symptom burden, respectively.

Conclusions:

• Next-generation sequencing has significantly advanced the understanding of airway microbiomes in chronic respiratory diseases.
• Targeted sequencing reveals associations between respiratory microbiome and disease outcomes, while metagenomics offers insights into functional pathways.
• Translating microbiome research into clinical practice for patient care, monitoring, and treatment remains a significant challenge requiring further investigation.