CT scans in children with severe asthma with and without persistent airflow limitation

<bold>Introduction:</bold> Computed Tomography (CT) scan abnormalities have been reported in paediatric severe asthma (SA), but the relationship with persistent airflow limitation (PAL) has not been established. <bold>Aims:</bold> We hypothesised that CT scan abnormalities in children with SA are related to airflow obstruction and aimed to assess the relationship with measures of airway physiology, inflammation, and morphology between children with and without PAL. <bold>Methods:</bold> Retrospective study of children with confirmed SA. PAL was defined as a post-bronchodilator, post-parenteral steroid FEV1 z-score of <-1.96. Anonymised CT scans were scored by a single-blinded radiologist for severity and extent of a range of measures, before a total lung score was calculated. Bronchoscopy was carried out within 12 months of the CT scan. <bold>Results:</bold> 80 children, median age 13.7 years (range 10.9-15.7) were included. 54 (68%) had an abnormal CT scan. 19 (24%) had PAL. Bronchial wall thickening was the most common abnormality, but this did not differ between groups(p= >0.999)(Table.1). There was no significant relationship between any of the CT scores and measures of lung function (FEV1, FVC, FEV1/FVC, bronchodilator reversibility). <bold>Conclusions:</bold> Chest CT scans are frequently abnormal in children with SA, but abnormalities are not related to lung function. Further work is warranted to assess how these abnormalities are related to long-term outcomes, particularly in adulthood.