In this single-center, retrospective study of chronic airway infections in PCD, chronic infection with PA was associated with a greater rate of pulmonary exacerbations but ppFEV1 decline was only associated with chronic AF infection.
Key Findings
Results
Chronic Pseudomonas aeruginosa infection was associated with a significantly higher pulmonary exacerbation rate in people with PCD.
The exacerbation rate ratio for chronic PA infection was 5.03 [95% CI 1.41, 18.0] (p = 0.013).
5 of 32 participants (16%) had chronic PA infection.
This was the only chronic infection type to reach statistical significance for exacerbation rate association.
Poisson mixed models were used to analyze the association of chronic infection with exacerbation rates.
Results
Chronic Aspergillus fumigatus infection was associated with lower percent predicted FEV1 in people with PCD.
A lower ppFEV1 was associated with chronic AF but not with other chronic infections.
2 of 32 participants (6%) had chronic AF infection.
The exacerbation rate ratio for chronic AF infection was 2.19 [95% CI 0.39, 12.30] (p = 0.373), which was not statistically significant.
Linear mixed effects models were used to analyze the association of chronic infection with ppFEV1.
Results
Chronic Haemophilus influenzae infection was not significantly associated with pulmonary exacerbation rate or ppFEV1 decline in PCD.
The exacerbation rate ratio for chronic HI infection was 1.29 [95% CI 0.72, 2.30] (p = 0.388).
Chronic HI was the most common chronic infection, occurring in 10 of 32 participants (31%).
No statistically significant association with ppFEV1 was found for chronic HI infection.
Results
Chronic methicillin-sensitive Staphylococcus aureus infection was associated with a non-significantly lower exacerbation rate ratio in people with PCD.
The exacerbation rate ratio for chronic MSSA infection was 0.41 [95% CI 0.16, 1.08] (p = 0.072).
2 of 32 participants (6%) had chronic MSSA infection.
The association did not reach statistical significance.
Results
The majority of the PCD cohort had at least one chronic airway infection.
32 people with PCD were included in the study.
19 of 32 (59%) had chronic infection of any type.
Chronic infections identified included PA (16%), HI (31%), MSSA (6%), and AF (6%).
This was a single-center, retrospective cohort study.
What This Means
This research looked at how chronic (long-lasting) bacterial and fungal lung infections affect outcomes in people with Primary Ciliary Dyskinesia (PCD), a rare genetic condition that impairs the tiny hair-like structures that normally clear mucus and germs from the airways. The study followed 32 people with PCD at a single center and found that 59% had at least one type of chronic airway infection, with the most common being Haemophilus influenzae (HI), followed by Pseudomonas aeruginosa (PA), and less commonly Staphylococcus aureus (MSSA) and Aspergillus fumigatus (AF, a fungus).
The study found that different infections had different effects on lung health. Chronic PA infection was linked to a five-fold higher rate of pulmonary exacerbations (episodes of worsening lung symptoms requiring treatment), which was a statistically significant finding. Chronic AF infection was associated with worse lung function as measured by a breathing test called FEV1. In contrast, chronic HI infection — despite being the most common — was not significantly associated with worse exacerbation rates or lung function decline.
This research suggests that the type of chronic infection matters when it comes to predicting how PCD may progress, with PA and AF potentially being particularly harmful pathogens in this population. However, because the study was small and conducted at only one center, further research with larger groups of patients will be needed to confirm these findings and to understand whether treating or preventing specific infections could improve long-term outcomes for people with PCD.
Saba T, Zimbric M, McCaffery H, Caverly L. (2026). Clinical Outcomes of Chronic Airway Infection in Primary Ciliary Dyskinesia.. Pediatric pulmonology. https://doi.org/10.1002/ppul.71828