The Study Of Subtype Of Asthma With Children Based On Induced Sputum Cytology

Background:There was now evidence that not all asthmatics are attributable to eosinophilic airway inflammation.Recently it had been suggested that patients with asthma could be divided into two(or more)inflammatory subtypes, eosinophilic and non-eosinophilic,The former was attributable to eosinophilic airway inflammation,the latter was attributable to non-eosinophilic airway inflammation.But so far there was no prospective study on inflammatory subtype of asthma with children in China.Objective:The aim of our study was to test the hypothesis that there are two(or more) inflammatory subtypes in the asthma with children according to induced sputum cytology.Method:46 children with exacerbated asthmatics and 33 with remission asthmatics, and 18 healthy control subjects were recruited,i e,56 mild to moderate asthmatics,23 severe asthmatics.Exacerbated asthmatics were divided into two groups,subjects in group 1(n =33)received only a short-acting inhaledβ₂-agonist as required,subjects in group 2(n=13)were all treated with inhaled steroid regularly.Lung function,skin prick test,EOS count of the peripheral blood,differential cell count of induce sputum,culture bacteria and mycoplasma were tested among the asthmatics.Statistical analysis was performed by using rank sum test,Chi-spquare or one-way factorial ANOVA.Correlations were measured using Spearman rank correlation(SPSS13.0).P values less than 0.05 were considered statically significant.Result:1.The percentage of EOS in the SI of group 1 was 0.0491±0.1836%,which was higher than that in remission asthmatics group and healthy control(P＜0.05),the percentage of EOS in the SI of group 2 was 0.0501±0.2138%,which was higher than that in remission asthmatics group and healthy control (respectively P＜0.05).The percentage of EOS in the SI of remission asthmatics was 0.0097±0.0255%,which was higher than that in healthy control (P＜0.05);There were no significant differences of NEU%in the SI between four groups(respectively P＞0.05).2.Based on the criteria of eosinophilic percentage≥2%,79 asthmatic subjects were divided into two subtypes,40 cases(50.63%)were EA and 39 cases(49.37%)were NEA.3.The percentage of EOS≥2%in the SI of group 1 was higher than that in remission asthmatics group(P＜0.05),but there was no significant difference between the group 2 and the group 1(P＞0.05)4.There was no significant difference between the group of mild asthmatics received only a short-acting inhaledβ₂-agonist as required and the group of mild asthmatics treated with inhaled steroid regularly(P＞0.05),as well as the same result was found in the severe asthmatics(P＞0.05)5.There were no significant differences between the positive rates of the skin prink test,allergic history of asthmatics and allergic family history among the subtypes of asthmatics with NEU%≥61%,EOS%≥2%,NEU%＜61%+EOS%＜2%(respectively P＞0.05). 6.The percentage of EOS in the SI was correlated negatively with ventilation parameter of lung function significantly(respectively P＜0.05),there was no correlation to the percentage of NEU in the SI and the lung function (respectively P＞0.05)Conclusion:1.The percentage of EOS in the SI of exacerbated asthmatics was higher than that remission asthmatics and healthy control(respectively P＜0.05)2. There were no significant differences of NEU%in the SI between three groups. 3.There were two subtypes in 79 asthmatic,i e EA and NEA.4.In the NEA subtype,there was 51.3%of cases to be NEU≥61%in the SI.5.There were no significant differences between the positive rates of the skin prink test, allergic history of asthmatics and allergic family history among the subtypes of asthmatics with NEU%≥61%,EOS%≥2%,NEU%＜61%+EOS%＜2%.6. The percentage of EOS in the SI was correlated negatively with ventilation parameter of lung function significantly,there was no correlation to the percentage of NEU in the SI and the lung function.