Airway Disease Progression on Chest Computed Tomography in Children With Primary Ciliary Dyskinesia

Rationale The longitudinal trajectory of airway disease on chest computed tomography (CT) and risk factors for progression in primary ciliary dyskinesia (PCD) is largely unknown. Methods Longitudinal analysis of structural airway disease among children with PCD enrolled in a prospective, multicenter observational study, stratified by ultrastructural defect group. CTs were scored utilizing the Melbourne‐Rotterdam Annotated Grid Morphometric Analysis for PCD, evaluating airway abnormalities in a hierarchical order: atelectasis, bronchiectasis (%BE), airway wall thickening, and mucus plugging/tree in bud opacities (%MP). Volume fraction of each component was expressed as % of total lung volume. %Disease (%DIS) is the sum of all components. Mixed effects regression analyses were utilized to describe the association between clinical predictors and CT scores adjusted for relevant covariates. Results Chest CTs ( N = 424) were obtained from 142 children over a mean (SD) of 4.9 (3.7) years. Mean (SD) age at first CT was 8.5 (4.6) years. Mean %DIS increased with age for the cohort (0.09% per year, 95% CI: 0.02–0.15, p < 0.01), driven by increased %BE (0.06 higher per year, 95% CI: 0.04–0.08, p = 0.0001) and increased odds of MP (1.14 higher odds per year, 95% CI: 1.08–1.21, p < 0.0001). Children with inner dynein arm and microtubular defects had increased mean %DIS and increased odds of MP compared to other ciliary abnormalities (1.73% higher, 95% CI: 0.71–2.74, p = 0.001; 3.21 higher odds per year, 95% CI: 1.73–5.95, p < 0.001). Annual increase in CT scores did not differ between defect groups. Conclusions Children with PCD experience progressive bronchiectasis and worsening mucus plugging with age.