ELEVATED SERUM EOSINOPHIL CATIONIC PROTEIN-LEVELS IN CYSTIC-FIBROSIS,PEDIATRIC ASTHMA, AND BRONCHIOLITIS

Serum levels of eosinophil cationic protein (ECP) may correlate with a ctivity in certain disease states, suggesting that eosinophils and the ir toxic granular products are involved in the pathogenesis of the dis ease, The aim of this study was to measure the serum concentration of ECP in patients with cystic fibrosis (CF), pediatric asthma, and viral bronchiolitis. The absolute number of blood eosinophils and IgE level s were determined simultaneously. Serum ECP levels were the highest in CF patients (median, 3101 mu g/L, +/- 463, N = 18), followed by those with asthma (median, 1113 mu g/L, +/- 795, N = 10) and those with vir al bronchiolitis (median, 1281 mu g/L, +/- 274, N = 9), Control patien ts with no infection or lung disease all had ECP levels between 2 and 58 mu g/L (median, 3.7 +/- 14.7 mu g/L, N = 10). The CF patients studi ed had a significantly higher level of ECP when compared to pediatric asthma and viral bronchiolitis patients (p = 0.008), There was no corr elation between the IgE level or absolute eosinophil count and the ECP level, Among the CF patients studied, the forced expiratory volume in 1 second (FEV(1)) and ECP level did show a significant inverse correl ation, (p < 0.01, probability). The finding of elevated ECP levels in CF patients indicates the presence of eosinophil activation in these p atients, The correlation between ECP and airflow obstruction suggests a role for activated eosinophils in disease pathogenesis.