Serum Eosinophil Cationic Protein Is a Useful Marker for Assessing the Efficacy of Inhaled Corticosteroid Therapy in Children with Bronchial Asthma.

Abstract

Bronchial asthma (BA) is a chronic inflammatory disorder of airways for which the effective therapies include inhaled corticosteroids (ICS) and short-acting β2-adrenoreceptor agonist (SABA). Serum eosinophil cationic protein (ECP) has been reported to reflect the degree of airway inflammation. We, therefore, explored the implication of serum ECP in assessing the efficacy of ICS therapy in BA children. Our prospective randomized control study enrolled 126 BA children and 78 healthy children (the control group). The BA patients were randomly assigned as two groups; 59 children were treated with ICS, twice a day, for three months and 67 patients received SABA inhalation only if necessary. After the 3-month therapy, the serum levels of ECP, endothelin-1, and nitric oxide and the eosinophil percentage (EOS%) in induced sputum were significantly lower in the ICS group, compared with the SABA group, but were still higher than the control group (all P < 0.05). The forced expiratory volume (FEV1%pred) and forced vital capacity (FEV1/FVC) were improved to the levels of the control group after therapy. Pearson correlation analysis presented that higher serum ECP levels were associated with higher EOS% in serum and with lower pulmonary function indices (FEVl%pred and FEV1/FVC). Importantly, the ICS group exhibited higher quality of life scores and lower symptom scores compared with the SABA group (all P < 0.05). ROC results revealed the diagnostic efficiency of serum ECP levels on the efficacy of ICS. In conclusion, measuring serum ECP levels is helpful for assessing the efficacy of ICS therapy in BA children.