• respiratory medicine
• child health
• paediatrics

Childhood bronchiectasis, unrelated to cystic fibrosis (CF), is still classed as an orphan disease. Historically it is poorly researched, falling behind the adult literature and other chronic lung conditions in paediatrics such as asthma and CF. Over recent years adult bronchiectasis has had a significant boost with the formation of several large registries such as EMBARC (European Multicentre Bronchiectasis Audit and Research Collaboration) and BronchUK (www.bronchiectasis.eu/registry, www.bronch.ac.uk). These registries have demonstrated that childhood and adult bronchiectasis can have similar aetiologies, for example postinfection and secondary to immunodeficiency, but have also shown differing potential causes and comorbidities, such as chronic obstructive pulmonary disease present in about 15% of adult cases.1 There remains in both adult and paediatric bronchiectasis a large population with unknown aetiology, especially within the paediatric literature where the prevalence appears high in indigenous communities.2

Thomas et al 3 explore a possible aetiology of bronchiectasis by examining its association with tracheomalacia. Within a historical cohort in a single tertiary paediatric centre, the degree of tracheomalacia, defined while performing a flexible bronchoscopy, was compared in children with or without evidence of bronchiectasis on a conventional high-resolution CT (c-HRCT) image. They report an increased proportion of any tracheomalacia seen in the bronchiectasis cohort. Using multivariable analysis, they demonstrate a further increase in significance of the association when tracheomalacia was …