Association of Neonatal Hospital Length of Stay with Lung Function in Primary Ciliary Dyskinesia.

Rationale: Primary ciliary dyskinesia (PCD), an inherited lung disease, is characterized by abnormal ciliary function leading to progressive bronchiectasis. There is wide variability in respiratory disease severity at birth and later in life. Objectives: To evaluate the association between neonatal hospital length of stay (neonatal-LOS) and supplemental oxygen duration (SuppO2) with lung function in pediatric PCD. We hypothesized that longer neonatal-LOS and SuppO2 are associated with worse lung function (i.e., forced expiratory volume in 1 second percent predicted [FEV1pp]). Methods: We performed a secondary analysis of the Genetic Disorders of Mucociliary Clearance Consortium prospective longitudinal multicenter cohort study. Participants enrolled, during 2006-2011, were <19 years old with a confirmed PCD diagnosis and followed annually for 5 years. The exposure variables were neonatal-LOS and SuppO2, counted in days since birth. The outcome, FEV1pp, was measured annually by spirometry. The associations of neonatal-LOS and SuppO2 with FEV1pp were evaluated with a linear mixed-effects model with repeated measures and random intercepts, adjusted for age and ciliary ultrastructural defects. Results: Included were 123 participants (male, 47%; mean enrollment age, 8.3 yr [range, 0 to 18 yr]) with 578 visits (median follow-up, 5 yr). The median neonatal-LOS was 9 d (range, 1 to 90 d), and median SuppO2 was 5 d (range, 0 to 180 d). Neonatal-LOS was associated with worse lung function (-0.27 FEV1pp/d [95% confidence interval, -0.53 to -0.01]; P = 0.04). SuppO2 was not associated with lung function. Conclusions: Neonatal-LOS is associated with worse lung function in pediatric PCD, independent of age and ultrastructural defects. Future research on the mechanisms of neonatal respiratory distress and its management may help us understand the variability of lung health outcomes in PCD.

Going beyond the chest X-ray: Investigating laterality defects in primary ciliary dyskinesia.

BACKGROUND: Organ laterality defects in primary ciliary dyskinesia (PCD) are common, ranging from complete mirror image organ arrangement, situs inversus totalis (SIT), to situs ambiguus (SA), which falls along the spectrum of situs solitus (SS) and SIT. Targeted investigations for organ laterality defects are not universally recommended in PCD consensus statements. Without investigations beyond chest radiography (CXR), clinically significant defects may go undetected leading to increased morbidity. We hypothesize that clinically significant SA defects remain undetected on CXR and targeted investigations are needed to detect various laterality defects associated with morbidity. METHODS: This retrospective study collected data from PCD clinics at two Canadian children's hospitals from 2012 to 2020. Participants <30 years old with a confirmed or clinical diagnosis of PCD were enrolled. CXR images were reviewed, and reports of other targeted investigations, including chest computed tomography, abdominal ultrasound, echocardiogram, upper gastrointestinal series, and splenic function studies, were extracted from medical records. Situs classifications from CXR alone versus CXR with add-on targeted investigations were compared using Cochran's q and McNemar tests. RESULTS: One hundred and fifty-nine PCD patients were included, median age at PCD diagnosis of 6.1 years (range: 0-28). The situs classification differed significantly from CXR images alone versus CXR with add-on targeted investigations (p < 0.001); SS 88 (55%) versus 75 (47%), SIT 59 (37%) versus 46 (29%), and SA 12 (8%) versus 38 (24%). Identified SA defects were cardiovascular (21, 13%), intestinal (9, 6%), and/or splenic (16,10%). CONCLUSIONS: In PCD patients, clinically significant SA defects may not be detected by CXR alone. Our results suggest that the routine use of CXR with add-on targeted investigations may be justified.