reported Nynke R. Bouma, BSc, and colleagues.
“Even though bronchiectasis is present in 60% to 80% of children with CF in school age, the extent and severity of bronchiectasis in preschool children are generally lower ... however, diffuse airway abnormalities such as airway wall thickening and mucus plugging are observed in many preschool children. It is hypothesized that these preschool airway changes reflect diffuse airway disease that eventually will result in bronchiectasis in school age,” they noted.
The PRAGMA-CF image scoring system can measure airway disease and can also be used to monitor disease progression, noted Ms. Bouma of Sophia Children’s Hospital, Rotterdam, and colleagues. The study was published in Pediatric Pulmonology. PRAGMA-CF is a composite score of airway wall thickening, mucus plugging, and bronchiectasis as percent disease (%disease). “In preschool children, %disease measured by PRAGMA-CF on chest CT allows quantification of early clinically relevant morphological features of CF airway disease and it is associated with later school-age bronchiectasis,” the team wrote. “These findings support the use of %disease as a clinically relevant outcome measure in early CF lung disease.”
The team conducted a prospective cohort study of 61 children (mean age 4 years) with cystic fibrosis, following them for a mean of 5 years. A total of 122 CT scans were available from this group, in addition to spirometry data and cystic fibrosis quality of life scores.
From preschool age to school age, the %disease on PRAGMA-CF increased significantly, from a mean of 0.7% to 1.73%. Scores on another composite measuring tool (%MUPAT, a composite score of airway wall thickening and mucus plugging) went from 0.46 to 0.58 – not a significant difference.
A multivariate analysis corrected for age in each school group and the type of scanner used to acquire the images. That analysis determined that each 1% increase in %disease at preschool age resulted in an increase of 1.18% of bronchiectasis at school age.
A cross-sectional analysis of the group at school age found significant associations between the %disease and percent of forced expiratory volume and the cystic fibrosis quality of life score.
At least one pulmonary exacerbation requiring intravenous antibiotics occurred in 19 of the patients. However, the investigators didn’t find any significant interactions between the %disease in preschool and these exacerbations..
“These findings are in line with previous studies in school‐aged children that showed that mucus plugging is associated with inflammation and airway wall thickening, and that these are thought to be risk factors for later bronchiectasis,” they concluded. “On the basis of our findings, we suggest that %disease and %MUPAT could be used as a clinically relevant outcome measure in clinical studies in preschool patients with cystic fibrosis, as these measures predict later bronchiectasis. Percent disease may be preferred as it captures all the principal features of CF airways disease including bronchiectasis.”
Ms. Bouma had no financial disclosures.
SOURCE: Bouma NR et al. Pediatr Pulmonol. 2019 Sep 9 doi: 10.1002/ppul.24498; Rosenow et al. Am J Respir Crit Care Med. 2015 May 15. doi: 10.1164/rccm.201501-0061OC.