RT Journal Article
SR Electronic
T1 Sputum microbiota in adults with CF associates with response to inhaled tobramycin
JF Thorax
JO Thorax
FD BMJ Publishing Group Ltd and British Thoracic Society
SP 1058
OP 1064
DO 10.1136/thoraxjnl-2019-214191
VO 75
IS 12
A1 Alya Heirali
A1 Christina Thornton
A1 Nicole Acosta
A1 Ranjani Somayaji
A1 Isabelle Laforest Lapointe
A1 Douglas Storey
A1 Harvey Rabin
A1 Barbara Waddell
A1 Laura Rossi
A1 Marie Claire Arrieta
A1 Michael Surette
A1 Michael D Parkins
YR 2020
UL http://thorax.bmj.com/content/75/12/1058.abstract
AB Background Inhaled tobramycin powder/solution (TIP/S) use has resulted in improved clinical outcomes in patients with cystic fibrosis (CF) with chronic Pseudomonas aeruginosa. However, TIP/S effect on the CF sputum microbiome has not been explored. We hypothesised that TIP/S has additional ‘off-target’ effects beyond merely P. aeruginosa and that baseline microbiome prior to initiation of therapy is associated with subsequent patient response.Methods We drew sputum samples from a prospectively collected biobank. Patients were included if they had one sputum sample in the 18 months before and after TIP/S. Bacterial 16S rRNA gene profiling was used to characterise the sputum microbiome.Results Forty-one patients met our inclusion criteria and 151 sputum samples were assessed. At baseline, median age was 30.4 years (IQR 24.2–35.2) and forced expiratory volume in 1 (FEV1) second was 57% predicted (IQR 44–74). Nineteen patients were defined a priori as responders having no net decrease in FEV1 in the year following TIP/S. No significant changes were observed in key microbiome metrics of alpha (within-sample) or beta (between-sample) diversity for samples collected before and after TIP/S. However, significant beta-diversity (Bray-Curtis) differences were noted at baseline between patients based on response status. Notably, responders were observed to have a higher abundance of Staphylococcus in pretherapy baseline samples.Conclusions Our longitudinal study demonstrates that the sputum microbiome of patients with CF is relatively stable following inhaled tobramycin over many months. Intriguingly, our findings suggest that baseline microbiome may associate with patient response to TIP/S—suggesting the sputum microbiome could be used to personalise therapy.