SERUM EOSINOPHIL CATIONIC PROTEIN IN THE EVALUATION OF ASTHMA SEVERITY IN CHILDREN

To assess the sensitivity and specificity of serum eosinophil cationic protein (ECP) in the diagnosis of asthma and evaluation of asthma sev erity, we conducted a prospective study to compare parameters of asthm a severity, peripheral blood eosinophilia, and serum ECP concentration s in 88 children presenting to a university hospital outpatient clinic with suspected (n=59) or recently diagnosed asthma (n=29). Serum ECP correlated significantly (r(s)=0.676, P=0.0001) with peripheral eosino phil counts, but only weakly with asthma severity (r(s)=0.21, P=0.046) . Serum ECP was significantly higher in atopic children (25+/-11 mu g/ l) than in nonatopic children (16+/-15 mu g/l) (P=0.01). Bronchial hyp erresponsiveness had no significant correlation (r(s)=-0.21, P=0.30) w ith serum ECP. Lung function test results had no (peak flow) or only a weak (FEV1) correlation with serum ECP, In distinguishing between chi ldren with and without asthma or in assessing asthma severity, serum E CP is not superior to the peripheral blood eosinophil count. The diagn ostic sensitivity and specificity of ECP in serum for detecting sympto matically active asthma, evaluated against the cutoff level of ECP in serum of 16 mg/l, were 54% and 71%, respectively.