title: Lung Clearance Index (LCI) in Patients with Bronchiolitis Obliterans: A Preliminary Report and Comparison to Cystic Fibrosis Patients.
abstract: Bronchiolitis obliterans (BO) is a chronic airway disease following an insult to the lower respiratory tract. Lung clearance index (LCI) measures ventilation inhomogeneity and has been studied in cystic fibrosis (CF). We aimed to evaluate LCI in BO and to compare it to LCI in CF patients.
  
  
  
  LCI was measured in BO patients, compared to CF patients, and correlated with spirometry and CT findings.
  
  
  
  Twenty BO patients and 26 CF patients (with similar mean age and BMI) underwent evaluation. FEV1 % and FEF25-75 % predicted were significantly lower in the BO group (60.5 ± 17.8 vs. 72.7 ± 20.7, p = 0.041, and 42.8 ± 22.8 vs. 66.4 ± 37.4, p = 0.017, respectively). In both groups, LCI was inversely correlated with FVC %, FEV1 %, and FEF25-75 % predicted. LCI  % was slightly higher (190.4 ± 63.5 vs. 164.9 ± 39.4, p = 0.1) and FRC gas % (measured by multiple breath washout) was significantly higher in the BO group (92.5 ± 35.9 vs. 71.3 ± 18, p = 0.014). The strength of statistical association between the lower FEF25-75 % values and the higher LCI values was stronger in BO patients.
  
  
  
  Similar to CF, LCI may provide estimation of ventilation inhomogeneity in BO. The results indicate greater small airway involvement and air trapping in BO. Further prospective longitudinal studies evaluating the correlation of LCI measurements with multiple clinical and physiological parameters should be performed to assess the clinical benefit of LCI measurement in BO.
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Gur
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.
authors.forename: Karin
authors.initials: K
authors.lastname: Yaacoby-Bianu
authors.affiliation: Pediatric Radiology Unit, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, Haifa, Israel.
authors.forename: Anat
authors.initials: A
authors.lastname: Ilivitzki
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.
authors.forename: Ronen
authors.initials: R
authors.lastname: Bar-Yoseph
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.
authors.forename: Vered
authors.initials: V
authors.lastname: Nir
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.|Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Fahed
authors.initials: F
authors.lastname: Hakim
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel.|Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Yazeed
authors.initials: Y
authors.lastname: Toukan
authors.affiliation: Pediatric Pulmonary Institute and CF Center, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, PO Box 9602, 31092, Haifa, Israel. l_bentur@rambam.health.gov.il.|Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel. l_bentur@rambam.health.gov.il.
authors.forename: Lea
authors.initials: L
authors.lastname: Bentur
mesh_terms: D000293:Adolescent; D001989:Bronchiolitis Obliterans / Q000503:physiopathology*; D002648:Child; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005260:Female; D005541:Forced Expiratory Volume; D005652:Functional Residual Capacity; D006801:Humans; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D012123:Pulmonary Ventilation; D012189:Retrospective Studies; D013147:Spirometry; D014797:Vital Capacity; D055815:Young Adult
keywords: Bronchiolitis obliterans; Computed tomography; Cystic fibrosis; Lung clearance index