Biomarkers in Bronchiectasis

• This is a biomarker of neutrophilic airway inflammation, which may help predict viral or bacterial infection.

• Examples include fractional exhaled nitric oxide, peripheral blood, and sputum eosinophils, which are associated with shorter time to first exacerbation.
• Higher peripheral eosinophil levels after treatment for Pseudomonas infection are associated with shorter time to first exacerbation.
• Low peripheral blood eosinophil endotype is associated with worse mortality and more severe disease.
• Blood and sputum eosinophils may be biomarker-responsive to inhaled corticosteroid therapy.

• Examples include neutrophil elastase, neutrophil extracellular traps, proteinase 3, myeloperoxidase, pregnancy zone protein, tumor necrosis factor-alpha, leukotriene B4, IL-1B, IL-8, and secretory leukocyte protease inhibitor.
• These are important targets that may be responsive to macrolide therapy in the long term and predict exacerbation rates.

• Examples include C-reactive protein, erythrocyte sedimentation, white blood cell count, platelet count, P-selectin, fibrinogen, and desmosine.

• Examples include Pseudomonas aeruginosa infection, microbiome biodiversity, total bacterial load, aspergillus sensitization, and infection.

Johnson E, Long MB, Chalmers JD. Biomarkers in bronchiectasis. Eur Respir Rev. 2024;33(173):230234. doi:10.1183/16000617.0234-2023

Chotirmall SH, Chalmers JD. The precision medicine era of bronchiectasis. Am J Respir Crit Care Med. 2024;210(1):24-34. doi:10.1164/rccm.202403-0473PP