Clinical significance of small airway function and inflammatory markers in induced sputum among patients with clinically controlled asthma / 中华全科医师杂志

ABSTRACT

Objective To investigate clinical significance of small airway function and eosinophil (Eos) percentage,levels of eosinophil cationic protein (ECP) and IL-5 in induced sputum among patients with clinically controlled asthma. Methods Sixty-two patients with clinically controlled asthma were selected for the study. Lung function was performed and percentage of Eos, levels of ECP and IL-5 in induced sputum were measured by Wrights' stain, fluorescence immuno-CAP system and ELISA,respectively. Thirty patients of asthma at acute exacerbation period and 20 healthy subjects were selected as controls. Results In 62 patients with clinically controlled asthma, 43 (69. 4% ) showed abnormal small airway function and 19(30. 6% ) normal one. Percentage of Eos [(5. 6 ±2. 9)%], levels of ECP [( 129 ±100) μg/L] and IL-5 [(21± 12) μg/L] in induced sputum were significantly lower in patients with clinically controlled asthma than those of asthma at acute exacerbation period [( 16. 2 ± 9. 7 ) %, ( 362 ±182) μg/L and IL-5(51 ±26) μg/L, respectively] (all P ＜0. 01 ), but significantly higher than those in healthy controls ( all P ＜ 0. 01 ). Percentage of Eos, levels of ECP and IL-5 in induced sputum were significantly higher in patients with clinically controlled asthma with abnormal small airway function than those with normal ane [(6.9±3.1)% vs. (2.0±1.1)%, (148±90) μg/Lvs. (54±29) μg/L and (24 ±12) μg/L vs. ( 13 ± 5 ) μg/L, respectively] ( all P ＜ 0. 01 ). Conclusions Abnormal small airway function and airway inflammation persistently exist in patients with clinically controlled asthma and it may be helpful to guild treatment during clinical control to determine small airway function and inflammatory markers in their induced sputum.