airway infection is associated with lung disease severity in children with cystic fibrosis.

Background: Despite the increasing prevalence of lung infection in patients with cystic fibrosis (CF), its clinical pathogenicity remains controversial. The objective of this study was to evaluate the effects of this emerging bacterium on lung disease severity in CF children.

Methods: This case-control retrospective study took place in two French paediatric CF centres. 45 cases infected by were matched for age, sex, genotypes and pancreatic status to 45 never-infected controls. Clinical data were retrieved from clinical records over the 2 years before and after initial infection.

Results: At infection onset, lung function was lower in cases compared with controls (p=0.006). Over the 2 years prior to acquisition, compared with controls, cases had more frequent pulmonary exacerbations (p=0.02), hospitalisations (p=0.05), and intravenous (p=0.03) and oral (p=0.001) antibiotic courses. In the 2 years following infection, cases remained more severe with more frequent pulmonary exacerbations (p=0.0001), hospitalisations (p=0.0001), and intravenous (p=0.0001) and oral antibiotic courses (p=0.0001). Lung function decline tended to be faster in cases (-5.5% per year) compared with controls (-0.5% per year).

Conclusions: This case-control study demonstrates that occurs more frequently in the patients with the worse lung disease. Further studies assessing the pathogenicity of this emerging pathogen and international treatment recommendations are warranted.