Early structural lung changes in young children with cystic fibrosis: a call to action.

Objective: Cystic fibrosis (CF) lung disease begins in early childhood, despite close follow-up and monitoring. Although imaging methods such as chest CT may detect structural changes before significant clinical manifestations, their role in preschool children remains debated. Evidence from low- and middle-income countries is limited. We sought to investigate the age at first chest CT, as well as imaging findings and their impact on treatment decisions. Methods: We conducted a retrospective cross-sectional study including children with CF attending a referral center in the city of São Paulo, Brazil, between 2009 and 2019. Clinical data were obtained from patient medical records and the Brazilian CF Registry database. Results: A total of 90 children were included, of whom 56.7% were male and 71.1% carried at least one F508del variant. The median age at CF diagnosis was 2.4 months (IQR, 1.5-4.5). The first chest CT was performed at a median age of 36.7 months (IQR, 28.1-47.8). Structural lung abnormalities were common, including air trapping (in 86.6% of the children), mucoid impaction (in 75.5%), bronchiectasis (in 45.5%), and atelectasis (in 35.5%), with only 4.4% of the scans being considered normal. Prescription of dornase alfa was based on CT findings in 74% of the cases, with initiation at a median age of 36.9 months (IQR, 28.9-57.6). A strong correlation was observed between age at first chest CT and age at initiation of dornase alfa therapy (r = 0.658; p < 0.001). Conclusions: Early chest CT revealed a high prevalence of structural lung disease in Brazilian infants and preschool children with CF and strongly influenced the initiation of dornase alfa.