Outcomes in protracted bacterial bronchitis (PBB): a five year prospective cohort study

Introduction: Protracted bacterial bronchitis (PBB), the commonest cause of chronic cough in childhood, is characterised by chronic wet cough (>4 weeks duration) that usually responds to 2-wks of appropriate antibiotic therapy without evidence of an alternative cause for cough. There are no long term studies on PBB beyond 2 yrs. Objectives: Characterise the 5 yr outcomes for children with PBB. Methods: 151 children (median age 26-mo, range 4-163) requiring bronchoscopy (FB) were recruited (PBB=130, controls=21). Participants were followed up for 5 yrs (min 42 mo). Participants were monitored with monthly contact via research staff and when possible annual clinical review and spirometry. CT chest was performed if symptoms/signs suggestive of bronchiectasis were present. Asthma was defined as a doctor diagnosis. Results: Of the 130 children with PBB, 88 (68%) had trachea/bronchomalacia on FB. CT chest was performed on 59 children (max 28 mo post FB), 11 (8.5%) had bronchiectasis. The incidence of recurrent PBB (>3 episodes/yr) decreased over study time from 70 (53.8%) in Yr-1 to 8 (15.7%) in Yr-5. However 38 (60.3%) required at least one course of antibiotics for an episode of wet cough in the preceding year. At the Yr-5 evaluation, 34 children with PBB (45.9%) had a diagnosis of asthma vs 2 (14%) in the controls (p Conclusion: Children with PBB should be followed-up as a significant proportion will eventually develop bronchiectasis and/or an asthma phenotype. Identifying clinical and/or lab-based markers (e.g. molecular signatures) at the index PBB episode would be useful for predicting future risk of disease.