Effect of montelukast on clinical score and cytokine levels of infants for clinically diagnosed acute bronchiolitis.

Background: Acute bronchiolitis comprises a major cause for morbidity in infants with viral infection which induces an immune inflammatory response that may produce long lasting harmful effects. Currently, there is no effective therapy for bronchiolitis.

Objective: Our aim was to investigate the efficacy of five-day montelukast therapy in acute bronchiolitis management.

Methods: The study included 50 infants with acute bronchiolitis. The infants with first episode of acute bronchiolitis were randomly assigned to receive daily montelukast dose of 4mg over five days after admission or no treatment. Plasma eotaxin, IL-4, IL-8 and IFN-gamma levels were evaluated before and after treatment by ELISA method. In the present study, the primary outcome measure was change in clinical severity score, whilst secondary outcome measures were changes in plasma eotaxin, IL-4, IL-8, IFN-gamma levels.

Results: No significant differences was found in clinical severity score with five-day montelukast treatment (p>0.05, Mann-Whitney U test). There were no significant differences in plasma eotaxin, IL-4, IL-8, IFN-gamma levels between the groups (p>0.05 Mann-Whitney U test). There was significant decrease in plasma IFN-gamma levels following five-day montelukast treatment (p=0.027, Wilcoxon). There were no significant differences in plasma IL-4, IL-8, IFN-gamma levels between the groups after five-day montelukast treatment (p>0.05, Wilcoxon). There was significant increase in eotaxin levels after five-day montelukast treatment (p=0.009, Wilcoxon).

Conclusion: Our study showed that montelukast affected plasma IFN-gamma and eotaxin levels after five days of treatment. Further studies are needed to demonstrate effects of montelukast on chemokine levels in bronchiolitis.