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

Abstract

Inhaled corticosteroids are capable of reducing the level of exhaled nitric oxide (expiratory nitric oxide fraction (FE,NO)) in asthmatic patients in a dosedependent fashion. The aim of this study was to evaluate whether or not treatment with an inhaled steroid can prevent changes in FE,NO after the exposure to relevant allergens, following avoidance, in asthmatic children allergic to house dust mite.Thirty-two house dust mite-allergy asthmatic children were randomly allocated to treatment with inhaled flunisolide (500 mg b.i.d.) or placebo and evaluated before and 2 weeks after a period of natural exposure to mite antigens. Lung function and FE,NO were evaluated.FE,NO was increased in the placebo-treated group after antigen exposure. Treatment 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 inflammation observed in allergic asthmatic children re-exposed to allergens. It is well recognized that asthma is an inflammatory disease and that indoor allergens, in particular house dust mite, represent a relevant factor in the aetiology of the disease [1]. It has been demonstrated that the development or worsening of asthma symptoms in children may be alleviated by allergen avoidance [2,3] or by suppressing the bronchial response to allergen challenge [4±9].In recent years, different markers have been proposed for the evaluation of level of airway inflammation [10]. Among these, the measurement of exhaled nitric oxide levels (expiratory nitric oxide fraction (FE,NO)) is considered a noninvasive means of assessing the degree of airway inflammation in asthmatics [11±13].Recent studies have shown that inhaled corticosteroids are capable of decreasing the FE,NO in asthmatic patients in a dose-dependent fashion [14,15].In this study, whether treatment with an inhaled steroid can prevent changes in FE,NO after a brief period of exposure to relevant allergens was evaluated in a group of asthmatic children allergic to house dust mite. Material and methods SubjectsThirty-two children (26 males and six females), ranging in age 6±15 yrs and with a history of bronchial asthma and a positive skin-prick test to house dust mite, were evaluated at the "Istituto Pio XII" long-stay hospital (Misurina, Belluno, Italy), situated at an altitude of 1,756 m in the Italian Alps. None of the patients had had respiratory infections for $2 months before the beginning of the study and none of them were allergic to furry pets.None of the children had received oral corticosteroids for $2 months or inhaled corticosteroids for $1 month before the study since they were staying in a house dust mite-free environment.The study was approved by the Istituto Pio XII Ethics Committee and both children and their parents gave informed consent. Study designThe study was performed between December 1997 and January 1998. The children admitted to the study had been living at the Istituto Pio XII, an environment fre...

Measurement of exhaled nitric oxide in children, 2001: E. Baraldi and J.C. de Jongste on behalf of the Task Force

“…In addition, a prompt decrease in the FENO levels was observed when mite-allergic asthmatic children moved to a mite-free mountain environment [135]. However, an increase in FENO was found after a short period of natural re-exposure to mite [136].…”

High‐altitude treatment: a therapeutic option for patients with severe, refractory asthma?

“…There was a decrease in serum total IgE and specific IgE to HDM [21], as well as a decrease in serum eosinophil cationic protein (ECP) and urine eosinophil protein X [20, 25]. Also, the percentage of eosinophils and epithelial cells in induced sputum [24, 27, 29], as well as the level of exhaled nitric oxide [28, 30–32] and the concentrations of cys ‐leukotrienes and 8‐isoprostane in exhaled breath condensate [27] were reduced after a few months' stay at high altitude. Forced expiratory volume in 1 s (FEV 1 ) did not change in most studies, but measures of small airways function (FEF 25–75 and residual volume) improved [23, 26, 29], and there was a significant improvement in deep‐breath‐induced bronchodilatation [35].…”

Measurement of exhaled nitric oxide in young children during tidal breathing through a facemask

“…Exhaled nitric oxide (eNO) could become a useful tool in diagnosing and monitoring airway inflammation in asthma (1–8). The methods employed for measurement of eNO can be categorized as either on‐line or off‐line methods.…”