Alternative inert gas washout outcomes in patients with primary ciliary dyskinesia

[摘要] The lung clearance index (LCI) derived from a nitrogen multiple breath washout test (N2-MBW) is a promising tool to assess small airways disease in primary ciliary dyskinesia; but it is difficult to apply in routine clinical settings because of its long measuring time. In this study; we aimed to assess alternative indices derived from shorter washout protocols.49 patients with primary ciliary dyskinesia (mean age 14.7xc2xb16.6xe2x80x85years) and 37 controls (mean age 14.3xc2xb11.4xe2x80x85years) performed N2-MBW and double-tracer gas (DTG) single-breath washout tests. Global (LCI and moment ratio (M2/M0)); conductive (Scond) and acinar ventilation inhomogeneity (DTG Slope III (SIII-DTG)) were determined for each individual. The main outcomes were 1) the ability to detect abnormal lung function from washout indices (>1.64 z-scores) and 2) measurement duration.The prevalence of abnormal values for LCI2.5% was 37 out of 47 (79%); for LCI5% was 34 out of 47 (72%); for M2/M0 was 34 out of 47 (72%); for Scond was 36 out of 46 (78%) and for SIII-DTG was 12 out of 35 (34%). Meanxc2xb1sd duration of measurement was 19.8xc2xb111.2xe2x80x85min for LCI2.5%; 10.8xc2xb14.6xe2x80x85min for LCI5% and 8.6xc2xb12.3xe2x80x85min for Scond.Compared to standard LCI2.5%; ventilation inhomogeneity was detected by LCI5%; moment ratio and Scond with comparable sensitivity while measurement duration was significantly shorter. Longitudinal studies will show which outcome is most suitable and practical in terms of sensitivity; duration and variability within the course of primary ciliary dyskinesia lung disease.

[学科分类] 呼吸医学