Korean J Asthma Allergy Clin Immunol.  2004 Sep;24(3):294-298.

Relation between Eosinophils in Induced Sputum and Severity of Exercise-Induced Asthma

Abstract

BACKGROUND
Exercise-induced asthma (EIA) is a common problem whose mechanism is not clearly understood. Few studies have been reported regarding the effect of eosinophilic airway inflammation on EIA. The aim of this study was to evaluate the relationship between the eosinophilic airway inflammation and the severity of EIA in asthmatic patients. METHOD: The percentage of eosinophils in induced sputum was determined in 21 asthmatic patients. To evaluate the severity of exercise-induced asthma, in all subjects the exercise provocation test was performed for at least 6 minutes and the maximal percentage fall in forced expired volume in one second (FEV1) was obtained. RESULT: The percentage of sputum eosinophils was significantly higher in EIA-positive subjects (n=11) than in EIA-negative subjects (n=10) (12.7% vs 4.7%, P=0.010). There was a significant correlation between sputum eosinophil counts and maximal percentage fall in FEV1 after exercise (r=0.459, P=0.036). CONCLUSION: Eosinophilic airway inflammation in asthmatic patients is correlated to the severity of exercise-induced asthma.

MeSH Terms

Asthma, Exercise-Induced*
Eosinophils*
Humans
Inflammation
Sputum*