Phenotyping in bronchiectasis: are we moving toward a personalized medicine?

Bronchiectasis (BE) is a heterogeneous disease. Similarly, to other chronic airway diseases, such as asthma and chronic obstructive pulmonary disease, management of BE patients requires a specific and personalized treatment that depends on many clinical, functional, and microbiological variables. Therefore, developing phenotyping methods that can help clinical and therapeutic choices is of paramount importance. Various methodological approaches have been used to personalize patients' management. In this review, we explore the main tools identified so far to classify and phenotype BE patients, including the approaches based on BE etiologies, disease severity, cluster analysis, and endotyping. We also discuss the strengths and limitations of every approach and highlight the similarities and differences between these studies. Finally, we review the therapeutic implications and clinical management connected with each approach.