Eosinophil cationic protein as a diagnostic marker for asthmatic children treated by immunotherapy.

We estimated the eosinophil cationic protein (ECP) levels in serum and sputum of 20 children with bronchial asthma to find whether it correlates with disease activity and examine the effect of immunotherapy. Ten-age- and sex- matched healthy children were also included. Children were subjected to full history, clinical examination and investigation including skin prick test, chest x-ray, complete blood count, and estimation of eosinophil cationic protein. In addition, examination of sputum to determine the eosinophil count and eosinophil cationic protein level was carried out. Patients were classified into 2 groups (10 patients each) according to the line of treatment used (5 mild and 5 moderate in severity). Group I received pharmacotherapy only and was followed for one year, while group II, received pharmacotherapy plus immunotherapy for one year. A significant increase in eosinophil count and ECP of blood and sputum was found in asthmatic patients as compared to controls. The ECP levels were significantly higher in moderate cases when compared with mild cases. On comparing levels of both eosinophil count and ECP in peripheral blood and sputum, before and one year after treatment, there was a significant reduction after therapy among the two groups of patients. The reduction was significant in group II. On the other hand there was a significant decrease in both symptoms and medication scores after one year of therapy. In conclusion, ECP may be a marker of eosinophilic activity and degranulation that correlates with the severity of bronchial asthma. Immunotherapy may be a good adjuvant therapy for atopic bronchial asthma of childhood.