TABLE 1

“Treatable traits” of bronchiectasis

TraitMain diseases that share the traitClinical featuresLaboratory/physiological featuresTargeted treatment
Chronic infectionProtracted bacterial bronchitisChronic wet coughGrowth of pathogens in respiratory secretionsAntimicrobials
Chronic bronchitis (COPD)
Ciliary dyskinesiaPCDYoung age of symptom onset, chronic otitis media, situs abnormalities, male infertility (asthenospermia), sinusitisLow nasal NO, electron microscopic abnormalities, abnormal ciliary beating patternInhaled saline, airway clearance, ongoing trial of ENaC inhibition
Secondary ciliary dyskinesia#
CFTR dysfunction/deficiencyCFYoung age of symptom onset, pancreatitis, malnutrition, bowel obstruction, male infertility (azoospermia), sinusitisElevated sweat chloride, characteristic electrophysiological abnormalities, CFTR mutations on two allelesCFTR modulators
CFTR-related disorder
Secondary CFTR dysfunction#
Immune deficiencyPrimary immune deficienciesYoung age of symptom onset, infection in extrapulmonary sitesImmunoglobulin deficiencies, impaired tests of immune functionIVIG
Secondary immune deficienciesHaematological malignancies
Systemic inflammationRheumatoid arthritisSymmetric arthritis, morning stiffnessRheumatoid factorDMARDs, CS, anti-TNF-α
IBDBloody diarrhoea, weight loss, GI ulcerationEndoscopic appearance and histologyAminosalicylates, CS, anti-TNF-α
Eosinophilic inflammationAsthmaSeasonalityAirway reversibilityICS, bronchodilators, anti-IgE, anti-IL-5
CRSChronic nasal discharge, loss of smell, facial painSinus inflammation on endoscopy, sinus CT
ABPAWheeze, mucus plugsElevated IgE, Aspergillus spp. sensitisation
Gastro-oesophageal refluxGORDSymptoms of heartburn and refluxEndoscopic, motility and imaging studiesBehavioural measures, proton-pump inhibitors, surgery

Examples of features of bronchiectasis that define a subgroup of patients. These may be viewed as “treatable traits” and some are shared with other disease entities. CFTR: cystic fibrosis transmembrane regulator; PCD: primary ciliary dyskinesia; NO: nitric oxide; ENaC: epithelial sodium channel; CF: cystic fibrosis; IVIG: intravenous immunoglobulins; DMARDs: disease modifying antirheumatic drugs; CS: corticosteroids; TNF: tumour necrosis factor; IBD: inflammatory bowel disease; GI: gastrointestinal; ICS: inhaled corticosteroids; Ig: immunoglobulin; IL: interleukin; CRS: chronic rhinosinusitis; CT: computed tomography; ABPA: allergic bronchopulmonary aspergillosis; GORD: gastro-oesophageal reflux disorder. #: may be induced by smoking.