USA: Pulmonary exacerbations remain a major clinical challenge in the early life of children with cystic fibrosis (CF), with new evidence highlighting their frequency, key risk factors, and long-term consequences.A large registry-based study, published in Pediatric Pulmonology by Aoife Corcoran, a Pediatric Pulmonary Attending at the Children’s Hospital of Philadelphia, Pennsylvania, USA, and colleagues, shows that pulmonary exacerbations during the first three years of life are common and are associated with poorer lung function and growth outcomes later in childhood.Using data from the Cystic Fibrosis Foundation Patient Registry, the researchers evaluated infants and young children with CF born between 2003 and 2017. The analysis included 7,342 patients who were diagnosed through newborn screening or at their first CF center visit by 60 days of age and who had continuous follow-up data available for the first six years of life. Nearly half of the children who experienced at least one pulmonary exacerbation were girls.The primary objective was to identify early-life factors associated with pulmonary exacerbations between ages one and three years. Secondary outcomes focused on nutritional status and lung function, measured as body mass index (BMI) z-scores around age three and percent predicted forced expiratory volume in one second (ppFEV1) at age six. Pulmonary function testing data at six years and BMI measurements between three and four years of age were used to assess longer-term outcomes. The study led to the following notable findings:About 35% of children with cystic fibrosis experienced at least one pulmonary exacerbation within the first three years of life, indicating very early disease activity.Nearly two-thirds of children who developed pulmonary exacerbations had their first episode during the first year of life.Medicaid insurance coverage was independently associated with a higher likelihood of early pulmonary exacerbations.Pancreatic insufficiency increased the risk of pulmonary exacerbations in early childhood.A diagnosis of asthma before the age of three was linked to a higher risk of exacerbations.Early use of hypertonic saline was associated with increased odds of pulmonary exacerbations.Positive infant respiratory cultures for methicillin-resistant Staphylococcus aureus or Stenotrophomonas maltophilia were associated with a higher risk of exacerbations.Exclusive breastfeeding for the first six months of life was associated with a significantly lower risk of pulmonary exacerbations compared with no breastfeeding.Children with more than one pulmonary exacerbation before age three had significantly lower percent predicted FEV1 values at age six.Even a single pulmonary exacerbation in early life was associated with lower BMI z-scores at age three, reflecting adverse effects on growth.According to the authors, these findings provide valuable insights for clinicians caring for very young people with cystic fibrosis. Identifying infants at higher risk of early pulmonary exacerbations may allow for closer monitoring, targeted interventions, and informed discussions with caregivers.”By recognizing both modifiable and non-modifiable risk factors, healthcare teams can better tailor early management strategies aimed at preserving lung function and supporting healthy growth during this critical developmental period,” they concluded. Reference:Corcoran, A., Bennett, L., Faerber, J. A., & Ren, C. L. (2025). Risk Factors and Outcomes of Pulmonary Exacerbations in Infants and Young Children With Cystic Fibrosis. Pediatric Pulmonology, 60(12), e71423. https://doi.org/10.1002/ppul.71423