Pneumologie 2015; 69 - A12
DOI: 10.1055/s-0035-1556604

Longitudinal dynamics of cystic fibrosis airways' microbiota during clinical stability and exacerbation

S Boutin 1, 2, M Stahl 2, 3, 4, SY Graeber 2, 3, 4, S Dittrich 2, 4, 5, MA Mall 2, 3, 4, A Dalpke 1, 2
  • 1Dept. of Infectious Diseases, Medical Microbiology and Hygiene, Univ. Heidelberg, Germany
  • 2Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL)
  • 3Div. of Pediatric Pulmonology & Allergology and Cystic Fibrosis Center, Dept. of Pediatrics, Univ. Heidelberg, Germany
  • 4Dept. of Translational Pulmonology, Univ. Heidelberg, Germany
  • 5Department of Pneumology and Critical Care Medicine, Thoraxklinik at the University Hospital Heidelberg, Germany

Introduction:

In the last decades, complexity of cystic fibrosis (CF) airways microbiota just started to get explored. However, most previous studies used cross-sectional designs thus obtaining snapshots of the lung microbiota at one time point. A longitudinal approach is needed to explore the stability of the CF microbiota over the time and to study the influence of acute pulmonary exacerbations and antibiotic therapy.

Methods:

In this pilot study, we collected and analyzed the lower airways microbiota (sputum and/or throat swabs) of 10 children with CF over a long timeframe (4 – 20 samples, 268 – 636 days). The microbiota was then explored by 16S amplicons sequencing with Illumina MIseq.

Results:

We found that longitudinal stability was mostly depending on the patients themselves and their individual microbiota. However, microbiota evenly composed of several genera including Prevotella, Streptococcus, Neisseria, Haemophilus and Veillonella seemed to be associated with increased stability and resistance to infections. Acute pulmonary exacerbations and subsequent antibiotic therapy influenced the stability of the microbiota in some patients. However, our data show that exacerbations are not necessarily correlated with dysbiosis.

Discussion:

Our results of this pilot study indicate that inter-individual variability is the most important parameter for stability. No clear correlations with clinical outcome were identified but it seems that stable patients exhibit a moderately even microbiota leading to resistance to common pathogens and infections. The protective effects of some genera (Prevotella, Streptococcus) were already demonstrated on a cross-sectional study and are confirmed here in a longitudinally sampled cohort. Surprisingly, a large part of exacerbation events was not correlated to a dysbiosis indicating that the cause of those exacerbations is probably not bacterial, which might question the common therapy of expanded antibiotic administration. An analysis involving more patients and time points will be necessary to clarify those points.

Supported by a grant from Gilead

*Presenting author