Exhaled nitrix oxide in asthma: relationship with blood eosinophils and total IgE

<bold>Background:</bold> Exhaled nitrix oxide (FeNO) is significantly increased in asthma (1). Purpose of the study. To assess the correlations between FeNO and blood eosinophils, total IgE <bold>Methods:</bold> This was a prospective study. FeNO were measured in 122 patients with asthma. FeNO were measured in patients with positive and with negative blood eosinophils. Total IgE was measured for 93 patients with asthma: 59 patients had positive IgE (≥240 ng/mL) and 34 patients had normal IgE (<240 ng/mL). Independent sample t-test and analysis of variance –ANOVA were used to compare the means of continuous variables. Significance was defined as a p value of <0.05. <bold>Results:</bold> The mean of FeNO in asthma is 41.7 (±36.6). The mean of FeNO in patients with positive blood eosinophils is 46.2(±24.9), with negative eosinophils is 37.8 (±36.2). There is significant difference between them (t=1.2 p=0.03). A statistically significant average correlation is observed between the % of blood eosinophils and FeNO(r=0.38p<0.01). FeNO in patients with normal IgE is 26.7(±26.8), with pozitive IgE is 53.9 (±44.7). There is significant difference between them (t=3.1 p<0.01). A statistically significant moderate correlation is observed between FeNO and total IgE (r=0.4 p<0.01) <bold>Conclusions:</bold> Measurement of FeNO in asthma is an important examination in the diagnosis of eosinophilic bronchial inflammation and be used to identify subjects with atopic asthma. Since there is a significant correlation between total IgE and FeNO, thus measurement of FeNO is not necessary as a diagnostic test but as a test to follow the efficacy of the medication in asthma. <bold>References:</bold> 1. P. Martins at al. exhaled nitric oxide in diagnosis and menagement of respiratory diseases.2009