目的：观察急性发作期哮喘患儿诱导痰中白细胞介素-5(IL -5)水平变化及其与哮喘发作期病情分度的关系，探讨其在哮喘发病机制中的作用和在临床诊治中的意义。方法：按随机分层设计，65例急性发作期哮喘患儿被分为 轻、中、重度发作组，34例健康儿童作为对照组。采用超声雾化高渗盐水诱导痰液，以酶联 免疫法(ELISA)测定诱导痰中IL5水平，同时进行诱导痰中嗜酸细胞(EOS)计数，测定用力 呼气比值(FEV-1)。结果：哮喘急性发作期患儿诱导痰中EOS计数、IL-5 水平均高于健康儿童组，FEV-1则低于健康儿童组，差异均具有显著性(P<0.01)。 急性发作期哮喘患儿轻、中、重度各组间诱导痰中EOS逐渐增高，但差异无显著性(P> 0.05)；而IL-5水平随发作程度的加重而明显升高，轻、中、重度发作各组间两两比较差异均有显著性(P<0.05)；重度哮喘患儿FEV-1低于轻、中度哮喘(P<0.05) 。痰液中IL-5水平与EOS计数之间呈显著正相关(r=0.482，P<0.05)，与F EV-1值之间呈显著负相关(r=-0.647，P<0.01)。结论：诱导痰中IL-5水平可能较EOS计数更能准确反映哮喘患儿气道炎症和哮喘发作时的病情程度，可以作为临床评价哮喘病情和药物疗效的准确灵敏的指标。

OBJECTIVE: To study the relationship between the change of interleukin 5 (IL 5) level in induced sputum and degrees of asthma attack in children with acute asthma, and to study the role of IL 5 in pathogenesis of asthma. METHODS: Sixty five cases of acute asthma were divided into 3 groups according to the degrees of asthma attack: mild, moderate and severe groups. Thirty four healthy children were served as the control group. Ultrasonically nebulized hypertonic saline was used to induce sputum. The IL 5 level in induced sputum was determined using ELISA. The forced expiratory ratio (FEV 1) and the eosinephils (EOS) counting in the sputum were measured. RESULTS: The EOS counting and IL 5 level in the induced sputum of children with acute asthma attack increased compared with those in the control group, whereas the FEV 1 decreased in the former (P<0.01 ). As asthma state became worse, EOS counting in induced sputum increased, but no significant difference was noted among different degrees of athma attack. The IL 5 level in the induced sputum was obviously different among the mild, moderate and severe cases [( 8.8 ± 4.9 ), ( 82.7 ± 173.5 ) and ( 225.1 ± 228.9 ) pg/ml, respectively] (P< 0.05 ). The FEV 1 in the severe group was significantly lower than those in the mild and moderate groups (P< 0.05 ). The IL 5 level in induced sputum was significantly positively correlated with EOS counting (r= 0.482 ,P< 0.05 ) and significantly negatively correlated with FEV 1 (r= -0.647 ,P< 0.01 ). CONCLUSIONS: Compared with EOS counting, the IL 5 level in induced sputum can more accurately reflect the degrees of asthma attack, indicating that it may be used as a sensitive index for evaluating the asthmatic state of children and the therepeutic effectiveness of drugs.