Serum ECP levels and methacholine challenge in infants with recurrent wheezing.
BACKGROUND
High levels of serum eosinophil cationic protein (sECP) as a marker of eosinophilic airway inflammation have been described as a predictor of childhood asthma. Bronchial hyperreactivity (BHR) appears to be secondary to the release of inflammatory mediators.


OBJECTIVE
We investigated the possible correlation between eosinophilic inflammation and BHR in 72 infants with recurrent wheezing.


METHODS
To determine bronchial reactivity, lung function measurements with methacholine challenge were performed in 72 infants, aged 12 to 30 months, and the degree of BHR to methacholine was compared with sECP values. Patients were grouped according to low (group 1, <10 microg/L, n = 22), medium (group 2, 10 to 20 microg/L, n = 23), and high (group 3, >20 microg/L, n = 27) sECP values.


RESULTS
In group 1, sECP levels ranged from 3.1 to 9.9 microg/L, mean 6.6 microg/L +/- standard deviation [SD] 2.3, in group 2, from 10.3 to 19.8 microg/L, mean 14.3 microg/L +/- SD 2.8, and in group 3 from 23.0 to 66.7 microg/L, mean 34.5 microg/L +/- SD 9.5. Distribution of provocative methacholine concentration among groups was as follows: group 1, 30 to 976 microg, mean 350.9 microg +/- SD 258.3; group 2, 36 to 752 microg, mean 340.7 microg +/- SD 226.3; group 3, 41 to 848 microg, mean 301.3 microg +/- SD 189.8 methacholine.


CONCLUSIONS
There was no significant correlation between sECP levels and bronchial reactivity in all groups (r = -0.076, P = 0.6), indicating that these parameters reflect two independent pathogenic mechanisms in the etiology of childhood asthma.
Reichenbach
Janine
J
University Children's Hospital Frankfurt am Main, Germany.
Jarisch
Andrea
A
Khan
Saima
S
Hömberg
Miriam
M
Bez
Christina
C
Zielen
Stefan
S
D001798:Blood Proteins / Q000378:metabolism*; D001985:Bronchial Provocation Tests / Q000379:methods; D016085:Bronchoconstrictor Agents; D002675:Child, Preschool; D047091:Eosinophil Granule Proteins; D004804:Eosinophils; D005260:Female; D006801:Humans; D007223:Infant; D018836:Inflammation Mediators / Q000097:blood*; D008297:Male; D016210:Methacholine Chloride; D012008:Recurrence; D012129:Respiratory Function Tests; D012135:Respiratory Sounds / Q000209:etiology / Q000503:physiopathology*; D012260:Ribonucleases
D001798:Blood Proteins; D016085:Bronchoconstrictor Agents; D047091:Eosinophil Granule Proteins; D018836:Inflammation Mediators; D016210:Methacholine Chloride; D012260:Ribonucleases