NP is a more severe disease with prolonged morbidity and hospitalization in spite of prior antibiotic treatment. All types had favorable outcome regardless of treatment-protocol. Complicated pneumonia has an ethnic predominance. Pediatr Pulmonol. 2017;52:247-254. © 2016 Wiley Periodicals, Inc.

The clinical spectrum of ciliopathies affecting motile cilia spans impaired mucociliary clearance in the respiratory system, laterality defects including heart malformations, infertility and hydrocephalus. Using linkage analysis and whole exome sequencing, we identified two recessive loss-of-function MNS1 mutations in five individuals from four consanguineous families: 1) a homozygous nonsense mutation p.Arg242* in four males with laterality defects and infertility and 2) a homozygous nonsense mutation p.Gln203* in one female with laterality defects and recurrent respiratory infections additionally carrying homozygous mutations in DNAH5. Consistent with the laterality defects observed in these individuals, we found Mns1 to be expressed in mouse embryonic ventral node. Immunofluorescence analysis further revealed that MNS1 localizes to the axonemes of respiratory cilia as well as sperm flagella in human. In-depth ultrastructural analyses confirmed a subtle outer dynein arm (ODA) defect in the axonemes of respiratory epithelial cells resembling findings reported in Mns1-deficient mice. Ultrastructural analyses in the female carrying combined mutations in MNS1 and DNAH5 indicated a role for MNS1 in the process of ODA docking (ODA-DC) in the distal respiratory axonemes. Furthermore, co-immunoprecipitation and yeast two hybrid analyses demonstrated that MNS1 dimerizes and interacts with the ODA docking complex component CCDC114. Overall, we demonstrate that MNS1 deficiency in humans causes laterality defects (situs inversus) and likely male infertility and that MNS1 plays a role in the ODA-DC assembly.

Lung PA colonization in PCD is associated with more severe disease as shown by the FEV and CT score. However, the magnitude of decline in pulmonary function was similar in colonized and non-colonized PCD patients.

Rationale: Historical studies suggest that airway infection in cystic fibrosis (CF) initiates with Staphylococcus aureus and Haemophilus influenzae with later emergence of Pseudomonas aeruginosa. Aspergillus species are regarded as relatively infrequent, late occurring infections. Objectives: To assess the prevalence and change in prevalence of early lower airway infections in a modern cohort of children with CF. Methods: All infants diagnosed with CF after newborn screening, participating in the AREST-CF cohort study between 2000-2018, were included. Participants prospectively underwent bronchoalveolar lavage (BAL) at 3-6 months,1 year and annually up to 6 years of age. Lower airway infection prevalence was described. Changes in prevalence patterns were assessed longitudinally using generalized estimating equations controlling for age and repeated visits. Measurements and Main Results: A total of 380 infants underwent 1,759 BALs. The overall prevalence and median age of first acquisition of the most common infections were: S. aureus 11%, 2.5yrs, P. aeruginosa 8%, 2.4yrs, Aspergillus species 11%, 3.2yrs, H. influenzae 9%, 3.1yrs. During the study, a significant decrease in prevalence of P. aeruginosa (p<0.001) and S. aureus (p<0.001) was observed with significant change towards more aggressive treatment. Prevalence of Aspergillus infections did not significantly change (p=0.669). Conclusion: Aspergillus species and P. aeruginosa are commonly present in the lower airways from infancy. The decrease in prevalence of P. aeruginosa and S. aureus since 2000, coinciding with more aggressive therapeutic approach, has resulted in Aspergillus becoming the most commonly isolated pathogen in young children. Further research is warranted to understand the implication of these findings.