Serum Endothelin-1 Immunoreactivity In Childhood Bronchial Asthma

Abstract

In a trial to evaluate the role of endothelin-1 in the pathogenesis of childhood asthma, 30 asthmatic and 30 healthy children were enrolled in the study. The asthmatic children were selected in a stratified non random manner ti•mn the Pediatric Allergy and Immunology Unit of Children's Hospital , Ain Shams University, and were studied during asthmatic attacks of varying severity and then followed up till disappearance of symptoms and they were re-evaluated . All subjects in the study were aged (6 •- 12 years). They were subjected to clinical evaluation, estimation of growth parameters and measurement of the absolute eosinophil count, total serum IgE and circulating plasma endothelin-1 (ET-1) activity by ELISA.

ET-1 immunoreactivity was significantly increased in the asthmatic children during the attacks (18.7 ± I 0.4 pg/ml) in comparison to the levels during quiescence of symptoms ( 1.4 ± 3.1 pg/ml). Moreover, both values were significantly higher than the control value (0.22 ± 0.3 pg/ml). Asthmatic severity did not significantly influence the ET-I results neither did the presence of increased bronchovascular markings on chest X-ray. We could not find a significant effect of steroid therapy on ET-1 levels. On the other hand, the total IgE levels were positively correlated to the ET-1 concentration while the absolute eosinophilic counts did not bear such a relation. Moreover, there was a positive correlation between the plasma ET-1 levels measured during the asthmatic attacks and those taken during quiescence