Sputum rheology critical stress is associated with non-cystic fibrosis bronchiectasis severity

<bold>Background:</bold> Sputum rheology is a very fast procedure that can inform on mucus characteristics and could help with disease management. The rheology critical stress value measures the force needed for the sputum to flow and is likely linked with airway clearance ability. We have previously shown that this parameter is associated with the asthma control questionnaire score in patients with severe asthma. <bold>Aim:</bold> To assess the relationship between sputum rheology and bronchiectasis severity index (BSI) in patients with non-cystic fibrosis bronchiectasis (NCFB) <bold>Methods:</bold> Sputum rheology and differential cell count were performed on 20 spontaneous sputum samples from patients with NCFB and associated clinical data was collected under the framework of the ManARTs biobank. Bronchiectasis severity index was calculated retrospectively using a combination of clinical, radiological and microbiological parameters. Pearson's correlation was calculated with IBM SPSS. <bold>Results:</bold> Of the 20 patients that consented to the study and provided a sputum sample, BSI was available for 13. There was a positive correlation between the BSI and the rheology critical stress value (r=0.61, <italic>p</italic>=.027, Figure 1). <fig><object-id>erj;64/suppl_68/PA4826/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> <bold>Conclusions:</bold> As the BSI became more severe, the force required for the sputum to start to flow increased. Although further investigations are needed, sputum rheology can inform on sputum behaviour with the potential for clinical management applications