HRCT chest findings in Th2 high severe asthma patients considered for biological therapies.

<bold>Introduction:</bold> High resolution computerised tomography (HRCT) chest scans were routinely performed in Th2 high severe asthma patients considered for biological therapies. Radiological findings can vary in different phenotypes of asthma. <bold>Aims:</bold> To evaluate the frequency of radiological abnormalities in different phenotypes of Th2 high severe asthma patients. <bold>Methods:</bold> HRCT performed during inspiration and expiration and reported by radiologists were retrospectively analysed. Using blood eosinophils ≥0.3x 10⁹/L, FENO >25ppb and Total IgE >30 KU/L, Th2 high severe asthma patients were then categorized into Allergic, Eosinophilic, and Eosinophilic-Allergic phenotypes. <bold>Results:</bold> HRCT were performed in a total of 140 Th2 high severe asthma patients. Abnormal HRCT were detected in 76% of patients. Findings related to asthma include Bronchial wall thickening(37%), Bronchial wall dilatation(9%), Bronchiectasis(21%), Air trapping(10%), large airway collapse(15%), ground glass opacities(6%), mosaic pattern(6%) and mucus plugging(11%). Each abnormal finding is further distributed amongst 3 phenotypes with total equalling 100%. <table-wrap><object-id>erj;64/suppl_68/PA4806/T1</object-id><object-id>T1</object-id><object-id>t1</object-id><table><colgroup><col></col><col></col><col></col><col></col><col></col><col></col><col></col><col></col><col></col></colgroup><tbody><tr><td> <bold>HRCT findings</bold> <bold>Phenotype</bold> </td><td><bold>Bronchial wall thickening</bold></td><td><bold>Bronchial wall dilatation</bold></td><td><bold>Air trapping</bold></td><td><bold>Bronchiectasis</bold></td><td><bold>Ground glass opacities</bold></td><td><bold>Mosaic pattern</bold></td><td><bold>Large airway collapse</bold></td><td><bold>Mucus plugging</bold></td></tr><tr><td><bold>Allergic</bold></td><td>14%</td><td>17%</td><td>8%</td><td>17%</td><td>0%</td><td>13%</td><td>0%</td><td>19%</td></tr><tr><td><bold>Eosinophilic</bold></td><td>19%</td><td>25%</td><td>21%</td><td>21%</td><td>22%</td><td>37%</td><td>29%</td><td>0%</td></tr><tr><td><bold>Eosinophilic-Allergic</bold></td><td>67%</td><td>58%</td><td>71%</td><td>62%</td><td>78%</td><td>50%</td><td>71%</td><td>81%</td></tr></tbody></table></table-wrap> Other findings include emphysema(5%), incidental nodules(18%), interstitial lung disease(2%) and lung cancers(0%). <bold>Conclusion:</bold> Performing HRCT chest prior to offering biological agents in Th2 high severe asthma patients help identify abnormalities that may need clinical management.