HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS REGISTER		Author Keyword(s) Vol Page [Advanced]

This Article Full Text Full Text (PDF) All Versions of this Article: thx.2007.077784v1 63/2/129    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this link to a friend Similar articles in this journal Similar articles in PubMed Add article to my folders Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gustafsson, P M Articles by Lindblad, A Search for Related Content PubMed PubMed Citation Articles by Gustafsson, P M Articles by Lindblad, A Topic Collections Related Article

Multiple-breath inert gas washout and spirometry versus structural lung disease in cystic fibrosis

¹ Queens Silvia Children’s Hospital and Department of Pediatrics, The Sahlgrenska Academy at Göteborg, Sweden
² Erasmus Medical Center-Sophia Children’s Hospital, Department of Pediatric Pulmonology and Allergology, Rotterdam, The Netherlands
³ Meander Medical Center, Department of Radiology, Amersfoort, The Netherlands
⁴ University Medical Center Utrecht, Department of Radiology, Utrecht, The Netherlands

Correspondence to:
Dr P M Gustafsson, Department of Paediatric Clinical Physiology, Queen Silvia Childres Hospital, S-416 85 Göteborg, Sweden; per.gustafsson{at}vgregion.se

Background: A sensitive and valid non-invasive marker of early cystic fibrosis (CF) lung disease is sought. The lung clearance index (LCI) from multiple-breath washout (MBW) is known to detect abnormal lung function more readily than spirometry in children and teenagers with CF, but its relationship to structural lung abnormalities is unknown. A study was undertaken to determine the agreements between LCI and spirometry, respectively, with structural lung disease as measured by high-resolution computed tomography (HRCT) in children and teenagers with CF.

Methods: A retrospective study was performed in 44 consecutive patients with CF aged 5–19 years (mean 12 years). At an annual check-up inspiratory and expiratory HRCT scans, LCI and spirometric parameters (forced expiratory volume in 1 s (FEV₁) and maximal expiratory flow when 75% of forced vital capacity was expired (FEF₇₅)) were recorded. Abnormal structure was defined as a composite HRCT score of >5%, the presence of bronchiectasis or air trapping >30%. Abnormal lung function was defined as LCI above the predicted mean +1.96 residual standard deviations (RSD), or FEV₁ or FEF₇₅ below the predicted mean –1.96 RSD. Sensitivity/specificity assessments and correlation analyses were done.

Results: The sensitivity to detect abnormal lung structure was 85–94% for LCI, 19–26% for FEV₁ and 62–75% for FEF₇₅. Specificity was 43–65% for LCI, 89–100% for FEV₁ and 75–88% for FEF₇₅. LCI correlated better with HRCT scores (Rs +0.85) than FEV₁ (–0.62) or FEF₇₅ (–0.66).

Conclusions: LCI is a more sensitive indicator than FEV₁ or FEF₇₅ for detecting structural lung disease in CF, and a normal LCI almost excludes HRCT abnormalities. The finding of an abnormal LCI in some patients with normal HRCT scans suggests that LCI may be even more sensitive than HRCT scanning for detecting lung involvement in CF.

This article has been cited by other articles:

				F. Santamaria, S. Montella, H. A. W. M. Tiddens, G. Guidi, V. Casotti, M. Maglione, and P. A. de Jong Structural and Functional Lung Disease in Primary Ciliary Dyskinesia Chest, August 1, 2008; 134(2): 351 - 357. [Abstract] [Full Text] [PDF]

				A. Bush Update in Pediatric Lung Disease 2007 Am. J. Respir. Crit. Care Med., April 1, 2008; 177(7): 686 - 695. [Full Text] [PDF]

				J. C Davies, S. Cunningham, E. W F W Alton, and J A Innes Lung clearance index in CF: a sensitive marker of lung disease severity Thorax, February 1, 2008; 63(2): 96 - 97. [Full Text] [PDF]