[Early lung disease in cystic fibrosis].

Recent data has shown that lung inflammation and infection subvene very early in very young infants with Cystic Fibrosis (CF). This leads to impaired lung function and structural damage, even in asymptomatic children. In the CF-pig model constitutional airway narrowing is present at birth, and is associated with defective mucus migration, and impaired bacterial clearance. At the age of 3 months, 25% of screened CF infants show decreased lung function. Air trapping is also present in 68% and bronchiectasis in 28% of patients. At the same age, the presence of neutrophil elastase in the bronchoalveolar lavage is an ominous sign since it triples the risk of bronchiectasis at the age of 3 years. Since only very few drug therapies have been validated in the preschool children, adapted clinical trials are warranted in this age group. Early interventions may have a huge impact on the natural history of CF, on the condition of not interfering with normal lung growth.