As respiratory paediatricians, we were disappointed to see the negative results reported previously in the AZTEC trial1 as we have found it to be a useful treatment in a range of lung diseases affecting children. Although the effects are modest, there is compelling evidence to show azithromycin is useful in cystic fibrosis,2 3 primary ciliary dyskinesia4 and severe asthma.5 Despite a paucity of evidence, it is also widely used in children with protracted bacterial bronchitis6 as well as in those with bronchiolitis obliterans7 and interstitial lung disease.8

The first placebo-controlled randomised controlled trial of azithromycin in extremely low birth weight neonates was conducted in 2007.9 This small pilot study had just 19 children in the azithromycin group and 16 children in the placebo group. It nonetheless showed some promise, with a significant reduction…