Prediction of Severe Attacks of Exercise-induced Bronchial Asthma in Children using Immunological Blood Parameters

Abstract

Bronchial asthma is considered an umbrella diagnosis for various diseases with certain pathophysiological mechanisms (endotypes) and variable clinical manifestations (phenotypes). The phenotype of exercise-induced asthma is one of the most common variants of the disease in children and adolescents. The treatment tactic of acute asthma attack is unified and depends of the severity in contrast to preventive therapy the vector of which provides an individualized approach. However, the issues concerning the duration, frequency of administration and amount of drugs prescription not finally resolved. The purpose of the study was to evaluate the blood immunological parameters in patients with exercise-induced asthma phenotype to predict the severity of disease exacerbation and optimize the reliever therapy. Material and methods. We examined 43 children suffering from exercise-induced asthma. Two clinical groups were formed according to the severity of the exacerbation. The first group included 22 patients with moderate exacerbation of asthma, and the second group had 21 children with severe symptoms of the disease, which was interpreted as a severe asthma attack. There were not any significant differences by sex, place of residence, age and diseases duration among comparison groups. The obtained results showed a significant increase in the level of B-lymphocytes in patients of first clinical group (26.64 %) compared with children with severe exacerbation (20.40 %), increase content of T-lymphocytes (due to T-helper cells) in schoolchildren of the second clinical group (42.32 %) compared with patients with moderate asthma attack (33.32 %). The attributive risk of more severe disease exacerbation with B-lymphocytes ≤20 % and T- helper cells ≥20 % was 36.6 %, the relative risk was 1.9 with odds ratio 5.0. A significantly higher level of pharmazan-positive neutrophils in spontaneous and stimulated modifications of the nitro blue tetrazolium test was recorded in patients with moderate exacerbation (35.18 % and 45.09 %) compared with children of the second clinical group (19.33 % and 27.81 %). The content of neutrophils in the spontaneous nitro blue tetrazolium test ≤15 % allowed evaluating severe compared with moderate asthma attack with specificity of 95.5 %, positive predictive value of 90.9 %, and positive likelihood ratio 10.5. Conclusion. The use of certain immunological parameters allows working out an individual plan for asthma attacks and may reduce the frequency of severe exacerbations in children suffering from exercise-induced bronchial asthma