Abstract
Objectives: Bronchiolitis obliterans syndrome (BOS) diagnosis in children following allogeneic hematopoietic stem cell transplantation (HSCT) is based on detection of lower airway obstruction on spirometry and air-trapping/small airway thickening/bronchiectasis on high-resolution chest CT (HRCT). We assessed the relationship between spirometry indices and air-trapping on HRCT.
Methods: Data of children post-HSCT with and without BOS (NIH 2014 criteria) were analyzed. An age-specific low attenuation threshold (LAT) was defined as the average of (mean-1SD) lung parenchyma attenuation of 5 control subjects matched to each age subgroup of the post-HSCT patients. % HRCT lung volume with attenuation values < LAT was calculated. Association between % lung volume and FEV1/FVC was assessed.
Results: We analyzed data of: (i) 6 children post-HSCT/BOS (median age: 8.5 years [IQR 7, 15]; median FEV1/FVC z-score: -2.60 [-2.93, -2.14]); (ii) 6 children post-HSCT/no BOS (age: 13.5 years [9.8, 16.3]; FEV1 z-score: 0.44 [-0.30, 2.10]); and (iii) 40 controls without lung disease (age:11 years [8.3, 15.8]). Patients post-HSCT/BOS had significantly higher % lung volume below the age-specific LAT compared to patients post-HSCT/no BOS: median % volume 16.4 % (7.1, 37.2) vs. 0.61% (0.34, 2.79), respectively; P=0.004 (Mann-Whitney U test). An exponential model described the association between % HRCT lung volume below LAT and FEV1/FVC z-score (r2=0.76; p<0.001).
Conclusion: In children with BOS post-HSCT, air-trapping quantified by chest HRCT is associated with severity of airway obstruction as expressed by FEV1/FVC z-score.
Footnotes
Cite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 1221.
This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2020