Bronchial microbiome, PA biofilm-forming capacity and exacerbation in severe COPD patients colonized by P. aeruginosa

Abstract

Aim: The bronchial microbiome of severe chronic obstructive pulmonary disease patients colonized by Pseudomonas aeruginosa was analyzed using 16S rRNA gene sequencing to identify differences related to biofilm-forming capacity.

Patients & methods: Patient sputum samples from 21 patients were studied.

Results: Statistically significant differences related to biofilm-forming capacity were only found for genera with relative abundances <1%, and Fusobacterium was over-represented when biofilm-forming capacity was high. Genera with relative abundances >50% which increased from baseline were observed in 10/14 exacerbations, but corresponded to Pseudomonas only in three episodes, while other pathogenic genera were identified in seven.

Conclusion: The bronchial microbiome shows differences according with P. aeruginosa biofilm-forming capacity. Pathogenic microorganisms other than P. aeruginosa cause a significant part of the exacerbations in colonized chronic obstructive pulmonary disease patients.

Keywords: 16S rRNA; P. aeruginosa; biofilm; exacerbation; lung microbiome; severe COPD.