The prevalence of tracheobronchomalacia in children with Primary Ciliary Dyskinesia

Background: The estimated prevalence of tracheobronchomalacia (TBM) in the general population is about 1:2100 and is reported to be increased in patients with cystic fibrosis. We could find no reports of TBM prevalence in primary ciliary dyskinesia (PCD). Aims: To study the prevalence of TBM in children with PCD aged Methods: We performed a retrospective review of all children with confirmed or highly likely PCD at Oslo University Hospital undergoing transnasal flexible bronchoscopy (FB) between 2012–2019 for suspected TBM, atelectasis or diagnostic work-up, and who were assessed for TBM. TBM and lobar bronchomalacia (LBM) were defined as a subjective reduction of >50% in the airway cross-sectional area during quiet respiration or coughing. Results: We identified 22 (10F) patients, median (range) age 6.0 (0.4-15.3) yr who underwent FB; TBM was diagnosed in 7 (32%). 6 patients had LBM affecting at least one lobe, including 2 of 7 with TBM. In a further 8 patients with middle lobe atelectasis, LBM affecting the same lobe was present in 4. Excluding patients with atelectasis in whom LBM may be secondary, TBM or LBM was present in 10 (2:8, F:M) children (45%). One patient (no TBM/LBM) had chronic Pseudomonas Aeruginosa (PA) infection. Method: The high prevalence of TBM/LBM may partly be due to selection bias. Even allowing for bias, the prevalence was higher than expected and was not associated with chronic PA infection. These findings should be confirmed in larger studies.