Eosinophil soluble protein levels, eosinophil peroxidase and eosinophil cationic protein in asthmatic patients

Eosinophil granular proteins are useful eosinophil activation markers in as thmatic patients. In this study, eosinophil peroxidase (EPO) and eosinophil cationic protein (ECP) levels were assessed in different stages of bronchi al asthma in 123 patients suffering from intrinsic (n = 42) and extrinsic ( n = 81) asthma, with the aim of evaluating the difference in the protein le vels between both types of asthma and their importance as a severity marker of the disease. The geometric mean serum level of EPO was 12.3 +/- 2.17 ng /ml (mean +/- SD) in controls, and 38.6 +/- 3.4 ng/ml in the asthmatic pati ents. Mean ECP levels were 13.22 +/- 1.11 ng/ml in controls and 30.5 +/- 2. 38 ng/ml in patients. Depending on the asthma severity, the EPO levels were 30.4 +/- 4.35 38.7 +/- 5.29, and 54.46 +/- 9.46 ng/ml in mild, moderate an d severe asthmatics, respectively, with the differences being significant b etween the groups of patients with mild and severe asthma (p <0.001). ECP l evels were 24.23 +/- 3.37 in mild, 31.69 +/- 4.21 in moderate, and 37.61 +/ - 4.52 ng/ml in severe asthma. There were significant differences in ECP le vels between mild and moderate asthma (p <0.001) and between mild and sever e asthma (p <0.001). Peripheral eosinophil count was 157 +/- 20 eosinophils /mm(3) in controls, 334 +/- 35 eosinophils/mm(3) in mild asthmatics, 510 +/ - 87 eosinophils/mm(3) in moderate asthmatics and 658 +/- 72 eosinophil/mm( 3) in severe asthmatics, with significant differences between all groups (p <0.05-p <0.001). Serum EPO and ECP levels and peripheral eosinophil count were significantly greater in patients with active asthma than in patients with silent asthma (p <0.001). Significant negative correlations (p <0.001) were found between serum EPO levels and FEV1 (r(s) = -0.30), MEF25-75 (r(s ) = -0.33), MEF50 (r(s) = -0.34). There was also a significant (p <0.001) a nd negative correlation between ECP levels and FEV1 (r(s) = -0.31), MEF25-7 5 (r(s) = -0.3 1), MEF50 (r(s) = -0.32). A good positive correlation was fo und between peripheral eosinophil count and EPO levels (r(s) = 0.80, p <0.0 01), and ECP levels (r(s) = 0.67 p <0.001). We also found a significant pos itive correlation between clinical score and peripheral eosinophil count (r (s) = 0.54, p <0.001), EPO levels (r(s) = 0.46, p <0.001) and ECP levels (r (s) = 0.52, p <0.001).