Azithromycin therapy shows positive effect on lung perfusion in infants with cystic fibrosis, finds research

A new study published in the Journal of Cystic Fibrosis found that infants with cystic fibrosis who get azithromycin exhibit a decrease in the thickness of their bronchial walls and may benefit from improved lung perfusion.

The COMBAT-CF research examined the effectiveness of azithromycin as an anti-inflammatory medication in newborns with CF. From the time of diagnosis until the age of 3, children with CF identified by newborn screening were stratified by site and randomly assigned 1:1 to maintenance therapy with azithromycin or a placebo.

The main outcome measure was structural airway illness as determined by the manual Perth-Rotterdam Annotated Grid Morphometric for CF (PRAGMA-CF) grading technique using chest computed tomography images (CTs). At 3 years old, there were no discernible variations in PRAGMA-CF sub-scores across treatment groups. On the other hand, children treated with azithromycin had fewer exacerbations, fewer days needing antibiotic therapy, and less inflammation in their bronchoalveolar lavage fluid.

Reanalyzing of the COMBAT-CF CTs utilized the AI-based BA-method and an AI-based technique to assess low attenuation regions (LAR, trapped air) was the goal of the post hoc investigation. Yuxin Chen and colleagues postulated that children receiving azithromycin would have thinner bronchial walls and lower LAR than those receiving a placebo.

The CT scans of the lungs at 12 and 36 months were examined. Measures of BA-analysis for the BA-diameters are the artery (A), bronchial wall thickness (Bwt), bronchial outer wall (Bout), and bronchial inner wall (Bin). BA-ratios: Bwt/A and Bwa/Boa (bronchial wall area/bronchial outer area) for bronchial wall thickening, and Bout/A and Bin/A for bronchial widening. An automated technique was used to analyze low attenuation regions (LAR). BA-outcomes at 36 months were compared between treatment groups using a mixed-effect model.

Analysis was done on 228 CTs (59 placebo, 66 azithromycin). When compared to the placebo group, the azithromycin group expressed increased Bin/A (p = 0.001) and lower Bwa/Boa (p = 0.0034). Because of a decrease in artery diameters, which was associated with a decrease in LAR, Bout/A (p = 0.0088) was greater.

Overall, the favorable impact of azithromycin maintenance treatment is further supported by the automated BA-analysis, which revealed a decrease in bronchial wall thickness in young children with CF receiving azithromycin. Also, the azithromycin group showed a decrease in artery diameter, indicating that azithromycin has a beneficial effect on small airway disease and related lung perfusion. 

Source:

Chen, Y., Charbonnier, J.-P., Andrinopoulou, E.-R., Sly, P. D., Stick, S. M., & Tiddens, H. A. W. M. (2024). Azithromycin reduces bronchial wall thickening in infants with cystic fibrosis. In Journal of Cystic Fibrosis (Vol. 23, Issue 5, pp. 870–873). Elsevier BV. https://doi.org/10.1016/j.jcf.2024.04.001