Significance of certain genotypic characteristics to form exercise-induced bronchial asthma in children

Abstract

Accordingtoatopicalup-to-datedefinitionsuggestedinPRACTALL [1], exercise-inducedbronchialasthma (EIBA) isaseparatevariantofbronchialasthma (BA) whentransientbronchialobstructionassociatedwithphysicalactivityisdetected. ItsoccurrenceinchildrenwithoutBAisdeterminedas “bronchialspasm” or “exercise-inducedbronchialconstriction”[2, 3]. Exercise-inducedbronchialspasm (EIBS) isobjectivelydeterminedas10% reductionofFEV1 (forcedexpiratoryvolumein 1 second) andmorethanthatoftheinitialvalueafterappropriatebronchialprovocationtest[4, 5]. AlthoughthemostfrequenttriggerofEIBAisintensiveandrelativelylongphysicalactivity, thisdiseaseischaracterizedbyamulti-triggercharacterofexacerbationsalteringthecourseofBAintomoresevereone[6]. According to these authors in addition to physical activity the following triggers of BA are: meteorological factors (32,9%), acute respiratory viral infection (ARVI) of effect of cold (22,3%), pollen (19,0%), animal epidermis (14,4%), house dust (11,0%), and exposure to tobacco smoke (8,0%). AtthesametimetherearecertaindataprovingtheroleofageneticcomponentinthedevelopmentofBAasamultifactorialdisease[7-8]. These investigations deal with the study of the role of deletion gene polymorphism coding the activity of glutathione-S-transferase for the course of BA in children [9-10]. Atthesametime, itshouldbenotedthatpathogenesisofBAphenotypehasnotbeenstudiedcompletelyyet, whichisevidentinunsolvedquestionsofdiagnosticsandindividualizedapproachestotreatment. Modernscientificliteratureavailabledoesnotpresentsufficientevidenceconcerningthevalueofgeneticcomponent, anddeletionsofGSTT1andGSTM1 genesin particular, and/or mutation polymorphism of еNOSgene in the formation of exercise-induced bronchial spasm.