Importance of sputum and computed tomography assessments of airway neutrophil inflammation and mucus plugging in bronchiectasis management

<title>Extract</title> Non-cystic fibrosis bronchiectasis is a chronic lung disease characterised by abnormal permanently dilated airways with accumulated mucus in the lumen. The pathogenesis of the disease is now considered on the basis of “vicious vortex” theory: this includes airway dysfunction, such as ciliary dysfunction and mucus hypersecretion, inflammation, infection with pathogenic bacteria, and structural damages, such as airway dilation and lung destruction [1]. Mucus accumulation in the airways and chronic sputum symptoms are the main features of patients with bronchiectasis. Mucus is characterised by higher concentrations of mucins, such as MUC5B and MUC5AC, with greater solidity, which are associated with the severity of bronchiectasis and lower lung function [2]. Mucus plugging causes hypoxic conditions for neighbouring airway epithelium, and chronic airway epithelial hypoxia is associated with MUC5B production [3].