Abstract
Introduction: Bronchiolitis obliterans (BO) is a chronic disease in which a persistent inflammation leads to obstruction and obliteration of the small airways. There are several causes for BO including infections, stem cell-, and lung transplantation. The course of BO is variable and a diagnostic workup is desperately needed to avoid lung biopsy in milder cases. Lung Clearance Index (LCI) has repeatedly been shown to be superior to FEV1 to monitor small airway disease (SAD) (Kent, L. et al. J Cyst Fibros. 2014 ;13(2):123-38). Therefore LCI appears to be a good candidate to become a new surrogate outcome measure in trials focusing on BO
Methods: We examined 20 patients suffering from BO and 19 healthy controls (Median Age 15,3 vs. 16,0), in terms of lung function, bodyplethysmography and LCI (easy one pro ®). A correlation of LCI and MEF 25 was performed.
Results: LCI and RV/TLC were significantly elevated in patients compared to controls (Median LCI 10.28 vs. 7.1; RV/TLC 177 vs. 133). FVC, FEV1, FEV1/FVC and MEF25 of patients were significantly reduced. LCI was inversely correlated with MEF25; r = -0.79 and p < 0.0001. Over a period of two years most BO patients showed no change of the LCI, which underlines the stable state of the disease.
Conclusion: The SAD was demonstrated by reduced MEF25, and elevated RV/TLC and LCI values. The LCI was inversely correlated with MEF25. Future studies will evaluate if the LCI can be used as a surrogate marker of disease progression in BO.
- Copyright ©the authors 2016
