Randomised controlled trial of nebulised gentamicin in children with bronchiectasis.

Aim: Following trials of inhaled antibiotics in adults, this study investigates the efficacy of nebulised gentamicin to improve respiratory function in children with bronchiectasis.

Methods: This is a randomised, double-blind, placebo-controlled, crossover trial of 12-week nebulised placebo/gentamicin, 6-week washout, 12-week gentamicin/placebo. Participants were children (5-15 years) with bronchiectasis, chronic infection (any pathogen), and able to perform spirometry from a hospital bronchiectasis clinic. Primary outcomes were change in forced expiratory volume in 1 s (FEV ) and hospitalisation days. Secondary outcomes included sputum bacterial density, sputum inflammatory markers, additional antibiotics and symptom severity. Analyses were on an intention-to-treat basis.

Results: Fifteen children (mean 11.7-years-old) completed the study. There was no significant change in mean FEV (56%/55%, P = 0.38) or annual rate of hospital admissions (1.1/0, P = 0.12) between gentamicin and placebo, respectively. However, Haemophilus influenzae sputum growth (27% vs. 80%, P = 0.002) and bacterial density (2.4 log cfu/mL lower P < 0.001) improved with gentamicin. Sputum inflammatory markers interleukin-1β (P < 0.001), interleukin-8 (P < 0.001) and tumour necrosis factor-α (P = 0.003) were lower with gentamicin. Poor recruitment limited study power and treatment adherence was challenging for this cohort.

Conclusions: In this crossover study of nebulised gentamicin in children with bronchiectasis, there was a reduction in sputum bacterial density and inflammation. However, there were no major improvements in clinical outcomes and adherence was a challenge.