title: Interstitial lung disease and ANCA-associated vasculitis: a retrospective observational cohort study.
abstract: OBJECTIVE
  ANCA-associated vasculitis and interstitial lung disease (ILD) are uncommon conditions. The occurrence of both diseases in the same patient is increasingly recognized. Our aim was to ascertain the characteristics and outcomes of patients with ILD and ANCA-associated vasculitis.
  
  
  METHODS
  A retrospective observational cohort study was performed. Patients who presented to the Hammersmith Hospital, London, with ANCA-associated vasculitis [granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis (MPA) or Churg-Strauss syndrome] who also had ILD were included. Following hospital discharge, all patients were followed up in a multi-disciplinary vasculitis clinic. We recorded patient demographics, diagnostic tests, treatment, complications and mortality.
  
  
  RESULTS
  ILD was observed in 2.7% (n = 14) of our patients with ANCA-associated vasculitis (n = 510); all had MPO-ANCA and a clinical diagnosis of MPA, giving a prevalence of 7.2% in patients with MPA (n = 194). There was no significant difference in survival between patients with MPA and ILD and those with MPA alone.
  
  
  CONCLUSIONS
  It is important that physicians are aware of this clinical association and the presence of ILD should be considered in all patients with ANCA-associated vasculitis, especially those with MPO-ANCA. The possibility that patients with ILD may subsequently develop features of systemic vasculitis should also be remembered.
authors.affiliation: Department of Renal, Division of Medicine, Imperial College London, UK.
authors.forename: Nishkantha
authors.initials: N
authors.lastname: Arulkumaran
authors.forename: Naomi
authors.initials: N
authors.lastname: Periselneris
authors.forename: Gill
authors.initials: G
authors.lastname: Gaskin
authors.forename: Nicola
authors.initials: N
authors.lastname: Strickland
authors.forename: Philip W
authors.initials: PW
authors.lastname: Ind
authors.forename: Charles D
authors.initials: CD
authors.lastname: Pusey
authors.forename: Alan D
authors.initials: AD
authors.lastname: Salama
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D015267:Churg-Strauss Syndrome / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D015897:Comorbidity; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D055953:Microscopic Polyangiitis / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D008875:Middle Aged; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D015996:Survival Rate; D006113:United Kingdom / Q000453:epidemiology