Lung ultrasound in children with primary ciliary dyskinesia: is it able to detect structural and functional...

Primary ciliary dyskinesia (PCD) is a chronic disorder of mucociliary clearance that leads to recurrent respiratory infections and progressive structural lung disease. Lung ultrasound (LUS) is a radiation-free bedside imaging modality; however, its use in PCD is limited, and no validated scoring system is available. This study aimed to evaluate LUS findings in children with PCD; assess the relationship between LUS aeration score and clinical characteristics, pulmonary function parameters, and chest radiograph severity; and to describe ultrasound-detected atelectatic findings. This prospective cross-sectional study included children with PCD evaluated at a tertiary center between December 2025 and February 2026. Lung ultrasound was performed using a standardized 12-zone scanning protocol and assessed using a conventional LUS aeration score (0-36). Atelectasis was recorded as a separate sonographic finding and was not incorporated into the scoring system. Chest radiographs were evaluated using the modified Chrispin-Norman score (CNS), and spirometric measurements were obtained in eligible patients. Associations between LUS aeration score, radiographic severity, and clinical parameters were analyzed. A total of 42 children with primary ciliary dyskinesia were included, of whom 24 (57.1%) were male. The median LUS aeration score was 1.0 (0.0-2.0), and the median modified CNS was 4.0 (2.0-6.0). A moderate positive correlation was observed between the LUS aeration score and CNS (r = 0.430, p = 0.005). The LUS aeration score also showed a moderate positive correlation with the number of respiratory exacerbations in the previous year (r = 0.342, p = 0.026) and with the number of bronchiectatic lobes (r = 0.490, p = 0.001). Atelectatic findings detected by LUS were associated with significantly higher CNS scores (p = 0.031), although they were not associated with higher LUS aeration scores.

Lung ultrasound is a valuable, radiation-free, bedside, and reproducible imaging modality for assessing structural lung involvement in children with PCD. The LUS aeration score correlates with radiographic severity and clinical disease burden, supporting its potential role as a complementary tool in clinical follow-up. Atelectatic findings detected by LUS appear clinically significant and are associated with greater radiographic severity. However, according to current guidelines, atelectasis should be documented as an individual sonographic finding rather than included in the scoring system. Taken together, these findings suggest that lung ultrasound may help assess both structural lung involvement and overall disease burden in children with primary ciliary dyskinesia.

• Lung ultrasound is a radiation-free bedside tool, but its use in primary ciliary dyskinesia is limited and no validated LUS-based scoring system is available. • Atelectasis is a common and clinically important sign of lung disease in children with primary ciliary dyskinesia.

• In children with primary ciliary dyskinesia, the conventional LUS aeration score shows a moderate correlation with chest radiograph severity (modified Chrispin-Norman score), frequency of respiratory exacerbations, and the number of bronchiectatic lobes. • Ultrasound-detected atelectasis - documented as a separate descriptive finding according to current international guidelines - is linked to significantly higher radiographic disease severity, and lung ultrasound may serve as a radiation-free, complementary bedside tool for ongoing monitoring of structural lung disease in children with primary ciliary dyskinesia.