EOSINOPHIL AND MAST-CELL PARAMETERS IN CHILDREN WITH STABLE MODERATE ASTHMA

Mast cells and eosinophils are important cells that contribute to the process of inflammation in asthma either by activating other cells or by secreting products which are potentially toxic to the respiratory e pithelium. The influx of these cells in the airways and the secretion of toxic products by these cells is abrogated by inhaled corticosteroi ds. Methods - In a double blind randomised, placebo controlled, study in children with stable moderate asthma (N = 34, 15 children received fluticasone propionate (FP), an inhaled corticosteroid, and 19 childre n used a placebo), we investigated the influence of treatment with FP 100 mu g bd on Various parameters of inflammation: number of eosinophi ls, secretory products of eosinophils i.e. ECP and EDN (in serum and u rine) and a secretory product of mast cells, histamine, which is deter mined as the compound to which histamine is converted and excreted by the human body: NT-methyl-histamine. Results - Previously we reported that lung function increased and bronchial hyperresponsiveness decreas ed in the 30 children that completed the study during treatment with F P. In these children we found that none of the laboratory parameters o f inflammation changed significantly during treatment with either FP o r placebo. However, the decrease in urinary EDN almost reached signifi cance (P = 0.07). Conclusions - Our results indicate that the number o f eosinophils, serum ECP and EDN and urinary EDN as well as urinary N- T-methyl-histamine do not reflect asthma disease activity in children with stable moderate asthma. Our data on urinary EDN warrant further s tudy of the use of this parameter to monitor asthma in children.