European Respiratory Journal 2021 57: 2003390; DOI: 10.1183/13993003.03390-2020
In patients with bronchiectasis, chronic infection by Pseudomonas aeruginosa is strongly associated with poor clinical outcomes, including more symptoms, worse quality of life, enhanced lung function decline, more frequent exacerbations and a three-fold increase in mortality [1, 2]. Therefore, treatment of chronic P. aeruginosa airway infection has long been regarded as a key priority in the management of bronchiectasis [3, 4]. To this end, a number of previous studies have used inhaled or nebulised antibiotics in these patients, but results are conflicting [5–9]. Most of these studies failed to reach their primary endpoints, although several potentially beneficial effects were observed. In fact, a recent meta-analysis showed that inhaled antibiotic treatment reduces exacerbation frequency in these patients  and, indeed, the current European Respiratory Society guidelines recommended long-term use of inhaled antibiotics in patients with chronic P. aeruginosa infection and frequent exacerbations . Yet, many unanswered questions remain, including which is the best antibiotic agent, its dose and/or its method of administration, among others.
Decreased airway bacterial load may have impact on clinical outcomes in bronchiectasis. The iBEST study demonstrates that tobramycin inhalation powder reduces P. aeruginosa sputum density in a dose-dependent manner in patients with bronchiectasis. https://bit.ly/3miO9fY
Conflict of interest: O. Sibila has nothing to disclose.