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Notes: Blood eosinophils, and serum levels of the eosinophil proteins, eosinophil cationic protein (ECP) and eosinophil protein X (EPX) were measured in childhood asthma. Seventeen patients mean age 11–9 years who were symptomatic with asthma, were enrolled in a study examining the eosinophil counts and eosinophil proteins at the onset of study and after treatment in relation to changes in their baseline forced expiratory volume at 1 second (FEV1) and % predicted FEV1. The patients with symptomatic asthma were compared with 17 patients mean age 12.0 years with asymptomatic asthma maintained on daily inhaled steroid and 13 patients, mean age 12.0 years, without asthma but with urticaria who served as non-asthma controls. Patients with symptomatic asthma did not have significantly higher initial eosinophil counts compared with those with asymptomatic asthma (0.43 × 109/1 vs 0.26 × 109/1, P= 0.09) but had higher serum ECP levels (28.9 μ/1 vs 18.5 μg/1). Both asthma patient groups had significantly higher serum ECP levels (P〈0.01) than the controls (9.8 μg/1). After therapy consisting of increased dose of inhaled steroids and/or oral steroids, patients in the symptomatic asthma group demonstrated a significant rise in FEV1 (1.67 1/sec at Visit 1 vs 2.08 1/ sec at Visit 2, 1〈0.01). A similar rise was seen for % predicted FEV1. Patients in the asymptomatic asthma group showed no significant change in FEV1 between visits (2.23 1/sec vs 2.37 1/sec), which was verified with the % predicted FEV1, Patients in the symptomatic asthma group showed a significant decrease in ECP level following treatment (28.9 μ/1 to 9.6 μ/1. P〈0.001) while the values in the asymptomatic group did not change (18.6 μ/1 to 15.2 μ/1 not significant). There was a significant correlation between the initial ECP level in the symptomatic asthma group and the change in the FEV| with treatment. Serum EPX levels showed similar trends but there was no significant correlation between the initial EPX levels and the changes in FEV1. Neither did blood eosinophil counts show such a correlation. This data suggests that the changes in serum ECP levels correlate with the changes in lung function subsequently to anti-inflammation therapy.

Notes: Children less than 5 years of age with asthma were assessed for total eosinophil counts and scrum levels of the eosinophil proteins, eosinophil cationic protein (ECP) and eosinophil protein X (EPX). to determine whether these measurements would reflect eosinophilic inflammation in the airways. Initially 27 symptomatic patients, 14 atopic and 13 non-atopic were investigated. They had a mean age of 1.8 years and had never been treated with inhaled steroid and had not received Intal for 2 weeks prior to the assessment. The 14 atopic patients proved to have higher mean total eosinophil counts and serum levels of ECP and EPX than the 13 non-atopic patients (eosinophil counts 0.63 109/1 vs 0.26 × 109/1, P 〈 0.001; ECP 36.9 μg/1 vs 10.8 μg/1, P 〈 0.001; EPX 69.0 μg/1 v.s 19.6 μg/l, P 〈 0.01. Thirteen of these patients required treatment with daily doses of inhaled steroid and 11 had a repeal assessment (seven atopic and four non-atopic). The mean serum EC'P of the seven atopic patients had fallen significantly (40.6 to 22.9. P 〈 0.05) while the total eosinophil counts did not. These results suggest a difference in numbers and activity of eosinophils in a topic compared with non-atopic asthma in young children.To determine whether the results were influenced by treatment with inhaled steroids. 31 patients who were being treated with daily inhaled steroid underwent assessment when they were symptomatic (22 samples) or asymptomatic (19 samples). Of the 31 patients. 11 were atopic and 20 non-atopic, Atopic asthmatics had higher levels of eosinophils and serum ECP than non-atopic patients when symptomatic patients were compared, despite treatment with inhaled steroid.Finally, in order to determine whether the ECP correlates with atopy rather than asthma, 19 patients who were seen for assessment of a reaction to a food (usually peanut or egg) and who had a positive skin lest to the appropriate food were examined. Twelve of these patients had a history of intermittent asthma and a mean ECP of 31 9μg/I while seven patients had no asthma and a mean ECP of 13.4 μg/l (P 〈 0.05), The total eosinophil counts showed the same difference. This suggests that atopy in the absence of asthma may not be associated with an elevated eosinophil count or ECP level. The data suggest that atopy contributes lo childhood asthma, even in infancy, by mobilization and activation of eosinophils. Scrum ECP might be a useful measure of eosinophil activation in asthma of early childhood.

Notes: Childhood asthma often begins in children under 3 years of age. Allergy contributes to the severity and persistence of childhood asthma so we examined the application of mixed allergen RAST discs (Paediatric Mix, a mixture of food antigens and Phadiatop, a mixture of inhalants) to the diagnosis of allergy. One hundred and nine children with a median age of 3 years, 71.6% of whom had asthma, were first assessed by one allergist who recorded their atopic status as positive, negative or questionable, on clinical grounds. Serum from each of these patients was used to determine a total IgE and 13 RAST assays. A laboratory definition of atopy was defined as a serum IgE 〉 1 standard deviation from normal, plus one or more positive RAST assays. The laboratory results influenced the assessment of atopy in 41% of cases. The use of just two mixed allergen discs (Paediatric Mix and Phadiatop) correctly assigned the presence or absence of atopy with a sensitivity of 98% and specificity of 98%, compared with the full laboratory evaluation. Very young infants were often just positive to food allergens but the Phadiatop disc could be used to suggest the onset of immunological sensitivity to inhalant antigens. Thus the application of mixed allergen RAST discs facilitated the diagnosis of atopy in young children.