Distribution of early structural lung changes due to cystic fibrosis detected with chest computed tomography.
OBJECTIVE
To examine the distribution of early structural lung changes in clinically stable infants and young children with cystic fibrosis using chest computed tomography (CT).


METHODS
This cross-sectional study included 62 children aged 1-6 years with volume-controlled volumetric chest CT scans performed under general anesthesia as part of an early surveillance program. Each lobe was scored for presence and extent of bronchiectasis, mucus plugging, and air trapping using a semiquantitative score. The topographic distribution of structural abnormalities was evaluated by comparing the presence and extent of abnormalities in different lung regions and examining relationships between components.


RESULTS
Although bronchiectasis was most common in the right upper lobe, overall changes in lung structure were not more common or more extensive in the upper lobes. Rather, bronchiectasis was more common in the right lung (right lung 0.95, left lung 0.68, P = .003), and mucus plugging (upper 0.41, middle 0.41, lower 0.72, P = .028) and air trapping (upper 0.79, middle 0.48, lower 0.96, P < .001) were more common in the lower lobes. The extents of bronchiectasis (P < .001) and air trapping (P = .011) were greater in the right lung. Scans with bronchiectasis were also more likely to have coexisting mucus plugging (P = .008) and air trapping (P < .001).


CONCLUSIONS
Early structural lung disease is heterogeneously distributed in the lung. Quantitative scoring tools for studies using chest CT as an end point, and mechanistic studies that seek to better understand the pathogenesis of early cystic fibrosis lung disease, should take account of this differential topographic expression of disease early in life.
Telethon Institute for Child Health Research and Center for Child Health Research, The University of Western Australia, Perth, Australia. lmott@ichr.uwa.edu.au
Lauren S
LS
Mott
Judy
J
Park
Catherine L
CL
Gangell
Nicholas H
NH
de Klerk
Peter D
PD
Sly
Conor P
CP
Murray
Stephen M
SM
Stick
D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D007223:Infant; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D014057:Tomography, X-Ray Computed