PT  - JOURNAL ARTICLE
AU  - Anna Mulholland
AU  - David Broderick
AU  - Sarah Missen
AU  - Tom Fontaine
AU  - Fiona Radcliff
AU  - John Beca
AU  - Mike Taylor
AU  - Naveen Pillarisetti
TI  - The lower airway microbiota in infants with severe bronchiolitis is largely similar to the upper airway microbiota
AID  - 10.1183/13993003.congress-2019.PA4992
DP  - 2019 Sep 28
TA  - European Respiratory Journal
PG  - PA4992
VI  - 54
IP  - suppl 63
4099  - http://erj.ersjournals.com/content/54/suppl_63/PA4992.short
4100  - http://erj.ersjournals.com/content/54/suppl_63/PA4992.full
SO  - Eur Respir J2019 Sep 28; 54
AB  - Introduction: While bronchiolitis is regarded as a viral lower respiratory tract infection, there is some evidence for the perturbation of the airway microbiota in infants with bronchiolitis. Little is known about the lower airway microbiota in children with bronchiolitis due to difficulty obtaining samples.Aim: To describe the lower airway microbiota in comparison with upper airway microbiota in infants with severe bronchiolitis needing intubation and ventilation.Methods: Infants intubated with bronchiolitis in the paediatric intensive care unit were recruited and nasal swabs and non-bronchoscopic lavage were performed. Bacterial DNA was extracted and the V3-V4 region of the 16S rRNA gene was amplified and sequenced using Illumina MiSeq. The relative abundance of taxa and alpha diversity were calculated.Results: Ten infants (median age of 3 months) were sampled. Five children had RSV bronchiolitis and five had Rhinovirus bronchiolitis. Proteobacteria were the most abundant taxa in both upper and lower airway samples. In the lower airway samples, Haemophilus was the most abundant genus (mean relative abundance 67.7%), followed by Streptococcus (15.1%) and Moraxella (5.1%). This was very similar to the upper airway samples (mean relative abundance Haemophilus 42.2% followed by Streptococcus 18.1%, Prevotella 10.5% and Moraxella 6.7%).Conclusion: In infants with severe bronchiolitis, the lower and upper airway microbiota are largely similar in bacterial composition with dominance of Proteobacteria at the Phylum level and Haemophilus at the genus level.FootnotesCite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA4992.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).