Airway microbiota across age and disease spectrum in cystic fibrosis

Abstract

Our objectives were to characterise the microbiota in cystic fibrosis (CF) bronchoalveolar lavage fluid (BALF), and determine its relationship to inflammation and disease status. BALF from paediatric and adult CF patients and paediatric disease controls undergoing clinically indicated bronchoscopy was analysed for total bacterial load and for microbiota by 16S rDNA sequencing. We examined 191 BALF samples (146 CF and 45 disease controls) from 13 CF centres. In CF patients aged <2 years, nontraditional taxa (e.g. Streptococcus, Prevotella and Veillonella) constituted ~50% of the microbiota, whereas in CF patients aged ⩾6 years, traditional CF taxa (e.g. Pseudomonas, Staphylococcus and Stenotrophomonas) predominated. Sequencing detected a dominant taxon not traditionally associated with CF (e.g. Streptococcus or Prevotella) in 20% of CF BALF and identified bacteria in 24% of culture-negative BALF. Microbial diversity and relative abundance of Streptococcus, Prevotella and Veillonella were inversely associated with airway inflammation. Microbiota communities were distinct in CF compared with disease controls, but did not differ based on pulmonary exacerbation status in CF. The CF microbiota detected in BALF differs with age. In CF patients aged <2 years, Streptococcus predominates, whereas classic CF pathogens predominate in most older children and adults.

Composition of airway bacterial community correlates with chest HRCT in adults with bronchiectasis

“…20 Furthermore, a number of studies have demonstrated a narrowing in airway bacterial taxa and community diversity with disease progression, severity, antibiotic use and age. [21][22][23][24][25][26][27] The results from this study add to those reported by Rogers et al who reported a relationship between bacterial diversity and inflammation (sputum neutrophil count) in 41 patients with BE. In contrast to our study, Rogers et al did find that bacterial diversity was significantly positively correlated with FEV 1.…”

“…However, in a previous study, we observed differences between individuals diagnosed with mild to moderate COPD, smokers and healthy non‐smokers, where both community diversity and evenness were significantly lower in individuals with COPD when compared to both of the non‐COPD groups . Furthermore, a number of studies have demonstrated a narrowing in airway bacterial taxa and community diversity with disease progression, severity, antibiotic use and age …”

The persistence of Nontypeable Haemophilus influenzae fuels airway inflammation

“…Vicious cycles of chronic inflammation and infections have been associated with immunopathology and decline in pulmonary function [6,7]. The natural history of airway colonization in children with CF is initially characterized by the isolation of NTHi, Streptococcus pneumoniae and/or Staphylococcus aureus infection, followed by other pathogens such as Pseudomonas aeruginosa [8][9][10]. The pathogenic potential and contribution of P. aeruginosa or S. aureus to the CF morbidity has been deeply described and demonstrated in details [11,12].…”

The global phylogenetic landscape and nosocomial spread of the multidrug-resistant opportunistStenotrophomonas maltophilia

“…cystic fibrosis are at particular risk of S. maltophilia infection 10 . Although almost any organ can be affected, mere colonization needs to be discriminated from infections that mainly manifest as respiratory tract infections, bacteraemia, or catheter-related bloodstream infections 5 .…”