Exhaled nitric oxide in asthmatic children exposed to relevant allergens: effect of flunisolide

Inhaled corticosteroids are capable of reducing the level of exhaled nitric oxide (expiratory nitric oxide fraction (FE,NO)) in asthmatic patients in a dose-dependent fashion, The aim of this study was to evaluate whether or not treatment with an inhaled steroid can prevent changes in FE,NO after th e exposure to relevant allergens, following avoidance, in asthmatic childre n allergic to house dust mite. Thirty-two house dust mite-allergy asthmatic children were randomly allocat ed to treatment with inhaled flunisolide (500 mu g b.i.d.) or placebo and e valuated before and 2 weeks after a period of natural exposure to mite anti gens, Lung function and FE,NO were evaluated. FE,NO was increased in the placebo-treated group after antigen exposure, Tr eatment with inhaled flunisolide prevented such increase in FE,NO (p<0.001) . No change was observed in lung function parameters. Inhaled flunisolide is effective in preventing the increase in airway infla mmation observed in allergic asthmatic children re-exposed to allergens.