Impact and treatment of exacerbations in adults with bronchiectasis.

Exacerbations have a negative impact on inflammatory diseases of the airways and, in patients with bronchiectasis, severe exacerbations are associated with increased morbidity and mortality. Exacerbations are also associated with a decline in quality of life and lung function, greater local and systemic inflammation and clinically more severe forms of the disease. As a consequence, the majority of therapeutic clinical trials carried out in patients with bronchiectasis are aimed at preventing exacerbations, but there is a scarcity of scientific evidence on the best treatment once they occur. All of these elements, combined with the great heterogeneity of bronchiectasis and the influence of geographical and microbiological factors on its clinical presentations and aetiologies, mean that the recommendations of therapeutic guidelines vary. An international group of experts has now reached agreement on the definition of exacerbation in bronchiectasis for the inclusion of patients in clinical trials, although its validity in clinical practice has yet to be demonstrated.