title: Thin-section computed tomography findings before and after azithromycin treatment of neutrophilic reversible lung allograft dysfunction.
abstract: OBJECTIVE
  Recently a novel subgroup of bronchiolitis obliterans syndrome (BOS) has been described in patients after lung transplantation with high neutrophil counts in broncho-alveolar lavage and recovery of lung functional decline with azithromycin treatment. We aimed to describe the thin-section computed tomography (CT) findings of these neutrophilic reversible allograft dysfunction (NRAD) patients before and after azithromycin.
  
  
  METHODS
  A cohort of 100 lung transplant recipients with BOS were treated with azithromycin and underwent lung function testing, broncho-alveolar lavage and CT before azithromycin treatment and during follow-up. The 200 CT data sets were scored for bronchial dilatation, mucus plugging, centrilobular abnormalities, airway wall thickening, consolidation, ground glass and end-expiratory air trapping.
  
  
  RESULTS
  NRAD was characterized by more centrilobular abnormalities on CT (p = 0.03 for prevalence and p = 0.06 for severity) compared to non-responders. At follow-up NRAD patients showed improvement in all CT abnormalities including air trapping, but the degree of improvement in all CT abnormalities was significantly different between responders and non-responders (who showed progression of bronchus dilatation, consolidation and air trapping).
  
  
  CONCLUSIONS
  Within BOS patients those with NRAD differ from azithromycin non-responders by more centrilobular abnormalities on CT before azithromycin and improvement in bronchus dilatation, consolidation and air trapping during treatment.
authors.affiliation: Department of Radiology, Katholieke Universiteit Leuven, Leuven, Belgium. pimdejong@gmail.com
authors.forename: Pim A
authors.initials: PA
authors.lastname: de Jong
authors.forename: Robin
authors.initials: R
authors.lastname: Vos
authors.forename: Geert M
authors.initials: GM
authors.lastname: Verleden
authors.forename: Bart M
authors.initials: BM
authors.lastname: Vanaudenaerde
authors.forename: Johny A
authors.initials: JA
authors.lastname: Verschakelen
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017963:Azithromycin / Q000627:therapeutic use*; D001989:Bronchiolitis Obliterans / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D018893:Bronchoalveolar Lavage; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D016040:Lung Transplantation / Q000009:adverse effects / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000473:pathology; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D000900:Anti-Bacterial Agents; D017963:Azithromycin