It is important to understand the bacterial composition (microbiota) within the airways to then understand the effect it has on disease initiation, recurrence and progression. This can then also help to identify susceptible children and to develop appropriate treatment and prevention strategies. However, there is limited prospective data on the airway microbiota of children and how this relates to the development of bronchiectasis and clinical outcomes.


The aim of this study is to define the lower airway microbiota and level of inflammatory markers in children with protracted bacterial bronchitis and, using clinical follow-up data, to identify associations with those that develop bronchiectasis.


16SrRNA gene sequencing and quantitative PCR will be used on stored samples from 100 children with protracted bacterial bronchitis and gene expression studies will be performed to identify and measure inflammatory markers. These will be assessed in relation to the clinical course during follow-up, including whether bronchiectasis developed. This will also be assessed in relation to the clinical phenotypes defined from the phenotype study being conducted as part of the CRE.

This study is funded through the AusBREATHE CRE.

Lead investigator
Dr Robyn Marsh and Professor Lucas Hoffman
Chief investigator
Professor Shyamali Dharmage
Project type
Project period