Exhaled Nitric Oxide Concentration in Children with Asthma and Allergic Rhinitis: Association with Atopy and Bronchial Hyperresponsiveness

PURPOSE: A new airway inflammatory marker, exhaled nitric oxide(ENO) has been reported to correlate with bronchial hyperresponsiveness(BHR) and atopy. The purpose of this study was to analyze the relationship of ENO with BHR or atopy in patients with asthma and with allergic rhinitis. METHODS: The subjects consisted of 55 children with asthma, 17 with allergic rhinitis, and 14 healthy controls. The asthma group was subdivided into the atopic asthma group(n=37) and the nonatopic asthma group(n=18) and the allergic rhinitis group into BHR group(n=7) and non-BHR group(n=10). All were investigated with spirometry and measurements of ENO concentration. The correlations between ENO concentration and both methacholine PC20(provocative concentration causing a 20% decrease in forced expiratory volume in one second) and the number of allergen skin test positivity were analyzed. RESULTS: ENO concentrations of both asthma and allergic rhinitis groups were significantly greater than that of control(P<0.01). ENO concentration of atopic asthma was significantly greater than that of nonatopic asthma(P<0.01). In allergic rhinitis, ENO concentration did not differ according to the presence or absence of BHR(P=0.50). ENO concentrations correlated significantly with the number of skin test positivity(r=0.32, P=0.02) or methacholine PC20(r=-0.38, P<0.01) in asthma group, but not in the allergic rhinitis group(r=0.42, P=0.09; r=-0.06, P=0.83). CONCLUSION: In asthma patients, some pathogenetic mechanisms associated with atopy and BHR seem to influence ENO concentration. In allergic rhinitis patients, some factors other than BHR may be important in determining ENO concentration.

Comparison of Obesity between Children with Asthma and Healthy Children / 소아알레르기및호흡기학회지

PURPOSE: An increase in the prevalence of obesity and asthma over recent decades has been reported. While there is evidence of a positive association between asthma and obesity, there is no report about association between asthma and obesity in Korea. The aim of this study was to determine if obesity is more prevalent in children with asthma compared with healthy children and to determine if obesity is associated with atopy in children with asthma. METHODS: We studied 291 atopic asthmatic children, 85 nonatopic asthmatic children and 149 healthy children. BMI (kg/m2) and obesity index were calculated using height and weight which were measured on the same day of methacholine challenge test. Obesity was defined as percentile of BMI over 95 percentile. BMI, obesity index and prevalence of obesity were compared among the three groups. Association between obesity and PC20 was also assessed in asthmatics. RESULTS: The prevalence of obesity was similar for atopic asthmatic group (11.6%), nonatopic asthmatic group (11.7%) and healthy group (12.7%). The prevalence of being at risk of overweight was similar for atopic asthmatic group (18.2%), nonatopic asthmatic group (24.7%) and healthy group (18.1%). There was no difference in BMI and obesity index among the three groups. In asthmatics, obesity index was not correlated with PC20 and there was no difference in obesity index among the asthmatics classified by PC20; < 2 mg/mL, 2-8 mg/mL, 8-18 mg/mL. CONCLUSION: These results suggest that obesity is not associated with asthma. Further studies are needed to confirm these findings in general population, and a prospective study is needed to follow younger children through adolescence.

Comparison of Eosinophil Markers between Acute and Recovery Stages in Children with Mycoplasma pneumoniae Pneumonia

PURPOSE: Several studies have shown that increases of eosinophil markers are common findings of asthma and Mycoplasma pneumoniae infection, and eosinophil markers reflect the clinical stage of asthma. The purpose of this study was to investigate the change of eosinophil markers according to the clinical stage of Mycoplasma pneumonia. METHODS: The patient group consisted of 33 outpatient children with Mycoplasma pneumonia. Peripheral blood total eosinophil count(TEC) and serum eosinophilic cationic protein(ECP) level were measured at both acute and recovery stages and were compared between both stages. The patient group was subdivided into the wheezing(n=16) and the nonwheezing group(n=17), and the TECs and the ECPs of one group were compared with those of the other group. The correlation between Mycoplasma antibody titer and the eosinophil markers of acute stage were analyzed. RESULTS: In the whole patient group, the TECs and the ECPs of the acute stage were significantly higher than those of the recovery stage(P=0.018, P=0.005), but there were no differences in the TEC and the ECP between the wheezing and the nonwheezing group. In the wheezing group, there were no significant differences in the TEC and the ECP between acute and recovery stages. There were no correlations between acute stage Mycoplasma antibody titer and the eosinophil markers. CONCLUSION: Eosinophil markers reflect the clinical stage of Mycoplasma pneumonia and eosinophilic inflammations may continue even after the acute stage in wheezing patients with Mycoplasma pneumonia.