Bronchial responsiveness and serum eosinophil cationic protein levels in preschool children with recurrent wheezing.
BACKGROUND
Bronchial hyperresponsiveness is a universally recognized phenomenon of asthma, and increased levels of eosinophil cationic protein (ECP) have been identified in the serum of patients with asthma.


OBJECTIVE
To investigate whether enhanced bronchial responsiveness and elevated serum ECP levels are associated with recurrent wheezing in preschool children and to examine the possible relationship between these 2 variables.


METHODS
We recruited 130 children aged 4 to 6 years: 59 with at least 3 episodes of wheezing in the previous year (current wheezers), 38 with a documented history of wheezing before 3 years of age but no subsequent wheezing episodes (past wheezers), and 33 who had never experienced wheezing (nonwheezers). The children underwent methacholine bronchial provocation tests using a modified auscultation method and blood sampling for the measurement of ECP levels.


RESULTS
Current wheezers showed greater bronchial responsiveness than past wheezers and nonwheezers, as demonstrated by lower provocation concentrations that caused audible wheeze and lower provocation concentrations that caused a decline in oxygen saturation of at least 5% from baseline. Likewise, current wheezers had higher serum ECP levels than the other 2 groups. Among current wheezers, ECP levels showed a significant negative correlation with provocation concentrations that caused oxygen desaturation and a marginally significant correlation with provocation concentrations that caused audible wheeze.


CONCLUSIONS
Enhanced bronchial responsiveness and elevated serum ECP levels are associated with recurrent wheezing in 4- to 6-year-old children. These results suggest that wheezing during preschool years may be phenotypically similar to wheezing in older children.
Yu
Jinho
J
Department of Pediatrics, College of Medicine, Seoul National University, Seoul, Korea.
Yoo
Young
Y
Kim
Do Kyun
DK
Kang
Hee
H
Koh
Young Yull
YY
D001249:Asthma / Q000175:diagnosis*; D001980:Bronchi / Q000187:drug effects; D016535:Bronchial Hyperreactivity / Q000175:diagnosis*; D016085:Bronchoconstrictor Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D047150:Eosinophil Cationic Protein / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000494:pharmacology; D012008:Recurrence; D012135:Respiratory Sounds
D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride; D047150:Eosinophil Cationic Protein