Clinical Features and Management of Children With Primary Ciliary Dyskinesia in England

To provide detailed characterization of children with primary ciliary dyskinesia (PCD) from the National Health Service in England and compare lung function to children with cystic fibrosis (CF).

All children (n = 333) with PCD who had an annual visit at the nationally commissioned PCD centers in England during 2015 were included. Lung function was compared with 2970 children with CF from England’s National CF registry.

Visit data were evaluated for multiple factors, including height, weight, BMI, spirometry, audiometry, airway microbiology samples, and antibiotic use (prophylactic and exacerbations). Global Lung Initiative (GLI) equations were used to estimate z-scores for forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC). Hearing loss was defined as mild if 20–40 dB, moderate if 40–70 dB, severe if 70–95 dB, and profound if >95 dB.

The median age of children with PCD at the annual visit was 9.8 years, 52.6% were male, 36.6% white, and 36.3% Pakistani/British Pakistani. The median age of PCD diagnosis was 2.6 years and was much sooner (1.0 vs 6.0 years) if a patient had dextrocardia (53%) versus levocardia (47%). Spirometry demonstrated mean predicted (SD) FEV₁ z scores for children with PCD were −1.9 (1.4) and FVC scores were −1.3 (1.5). Overall FEV₁ was 76.8% in PCD and 85.0% in CF, and FEV₁ dropped significantly in older PCD children (decrease in 0.6 z score for every increase in 10 years). Compared with children with CF, the mean predicted FEV₁ was significantly lower in children with PCD up to age 15, with no difference from 16–18 years of age. The most substantial difference was at age 5–7 (FEV₁%, was 91.3% in CF versus 78.3% in PCD). Children with a lower BMI also had lower FEV₁ (P < .001). Microbiology data obtained from PCD children demonstrated only 33% cultured a respiratory pathogen, including Hemophilus influenza (17.9%), S aureus (5.1%), S pneumoniae (4.2%), and P aeruginosa (2.6%). No correlation existed between respiratory pathogens and FEV₁ scores. Hearing impairment was common, with 34% having a mild loss, 21.8% moderate loss, and 23.6% required hearing aids. 30% of children with PCD had at least one course of antibiotics over the preceding 12 months (average was two courses), with 10% requiring regular doses every 3–6 months. 59% were prescribed prophylactic antibiotics, and over half used azithromycin (59.8%). A significantly lower mean FEV₁ z score was found in children taking prophylactic antibiotics, adjusted for antibiotics and cultured pathogens (n = 162, regression coefficient: −0.66, 95% CI: −1.23 to −0.08, P = .0008, adjusted R² = 8.3%).

PCD is not a mild respiratory condition, and children with PCD often have worse lung function than children with CF, particularly at younger ages. Lower BMI correlated significantly with lower FEV₁.

This extensive national cross-sectional analysis of children with PCD illustrates this condition has an earlier and more significant decline in lung function than previously thought. Spirometry was significantly lower in children with PCD than children with CF, a group known to have significant respiratory impairment. This study also elucidated the additional care these children need including regular hearing screening and possibly prophylactic antibiotics. Like in CF, BMI had a significant predictive value for lung function and should be managed aggressively in this population.