title: Etiology of Non-Cystic Fibrosis Bronchiectasis in Adults and Its Correlation to Disease Severity.
abstract: BACKGROUND
  Testing for underlying etiology is a key part of bronchiectasis management, but it is unclear whether the same extent of testing is required across the spectrum of disease severity.
  
  
  OBJECTIVE
  The aim of the present study was to identify the etiology of bronchiectasis across European cohorts and according to different levels of disease severity.
  
  
  METHODS
  We conducted an analysis of seven databases of adult outpatients with bronchiectasis prospectively enrolled at the bronchiectasis clinics of university teaching hospitals in Monza, Italy; Dundee and Newcastle, United Kingdom; Leuven, Belgium; Barcelona, Spain; Athens, Greece; and Galway, Ireland. All the patients at every site underwent the same comprehensive diagnostic workup as suggested by the British Thoracic Society.
  
  
  RESULTS
  Among the 1,258 patients enrolled, an etiology of bronchiectasis was determined in 60%, including postinfective (20%), chronic obstructive pulmonary disease related (15%), connective tissue disease related (10%), immunodeficiency related (5.8%), and asthma related (3.3%). An etiology leading to a change in patient's management was identified in 13% of the cases. No significant differences in the etiology of bronchiectasis were present across different levels of disease severity, with the exception of a higher prevalence of chronic obstructive pulmonary disease-related bronchiectasis (P < 0.001) and a lower prevalence of idiopathic bronchiectasis (P = 0.029) in patients with severe disease.
  
  
  CONCLUSIONS
  Physicians should not be guided by disease severity in suspecting specific etiologies in patients with bronchiectasis, although idiopathic bronchiectasis appears to be less common in patients with the most severe disease.
authors.affiliation: 1 Health Science Department, University of Milan Bicocca, Azienda Ospedaliera San Gerardo, Monza, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Lonni
authors.affiliation: 2 Tayside Respiratory Research Group, University of Dundee, Dundee, United Kingdom.
authors.forename: James D
authors.initials: JD
authors.lastname: Chalmers
authors.affiliation: 3 Respiratory Medicine, University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Pieter C
authors.initials: PC
authors.lastname: Goeminne
authors.affiliation: 4 Department of Respiratory Medicine, Galway University Hospitals, Galway, Ireland.|5 Adult Bronchiectasis Service and Sir William Leech Centre for Lung Research, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Heaton, United Kingdom.
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: McDonnell
authors.affiliation: 6 5th Department of Pulmonary Medicine, "Sotiria" Chest Diseases Hospital, Athens, Greece.
authors.forename: Katerina
authors.initials: K
authors.lastname: Dimakou
authors.affiliation: 5 Adult Bronchiectasis Service and Sir William Leech Centre for Lung Research, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Heaton, United Kingdom.|7 Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Anthony
authors.initials: A
authors.lastname: De Soyza
authors.affiliation: 8 Thorax Institute, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), University of Barcelona, Pulmonary Division, Hospital Clinic of Barcelona, Barcelona, Spain; and.
authors.forename: Eva
authors.initials: E
authors.lastname: Polverino
authors.affiliation: 3 Respiratory Medicine, University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Van de Kerkhove
authors.affiliation: 4 Department of Respiratory Medicine, Galway University Hospitals, Galway, Ireland.
authors.forename: Robert
authors.initials: R
authors.lastname: Rutherford
authors.affiliation: 7 Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Davison
authors.affiliation: 8 Thorax Institute, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), University of Barcelona, Pulmonary Division, Hospital Clinic of Barcelona, Barcelona, Spain; and.
authors.forename: Edmundo
authors.initials: E
authors.lastname: Rosales
authors.affiliation: 1 Health Science Department, University of Milan Bicocca, Azienda Ospedaliera San Gerardo, Monza, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Pesci
authors.affiliation: 9 Division of Pulmonary Diseases and Critical Care Medicine, South Texas Veterans Health Care System and University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors.forename: Marcos I
authors.initials: MI
authors.lastname: Restrepo
authors.affiliation: 8 Thorax Institute, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), University of Barcelona, Pulmonary Division, Hospital Clinic of Barcelona, Barcelona, Spain; and.
authors.forename: Antoni
authors.initials: A
authors.lastname: Torres
authors.affiliation: 1 Health Science Department, University of Milan Bicocca, Azienda Ospedaliera San Gerardo, Monza, Italy.
authors.forename: Stefano
authors.identifier: http://orcid.org/0000-0002-0090-4531
authors.initials: S
authors.lastname: Aliberti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001987:Bronchiectasis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D003550:Cystic Fibrosis; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D012141:Respiratory Tract Infections / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: bronchiectasis; etiology; severity of illness index