title: Airway hyper-responsiveness to adenosine 5'-monophosphate in preschool-age children with asthma.
abstract: Airway hyper-responsiveness (AHR) to adenosine 5'-monophosphate (AMP) is closely associated with airway inflammation; however, not all asthmatic patients are responsive to it. This study was planned to investigate the predictive factors of AHR to AMP in asthmatic children aged between 3 and 6 yr. We performed a retrospective analysis of data from 63 asthmatic preschool-age children who were challenged by AMP in our department. All children were characterized by skin-prick tests, serum immunoglobulin E (IgE) levels, peripheral blood eosinophil percentage and bronchial challenge with methacholine (MCH) and AMP. Potential determinants for AHR to AMP were assessed within the group. AHR to AMP was found in 46% of preschool-age children with asthma, while that of MCH was 93.7%. All children responsive to AMP were also responsive to MCH. The geometric mean provocative concentration of MCH and AMP causing a 15% fall in transcutaneous oxygen tension (PC(15)PtcO(2)MCH and AMP) were 0.55 mg/ml (0.004-9.19) and 10.53 mg/ml (0.59-342.89), respectively. AMP-responsive children did not differ from non-responsive ones with respect to demographic factors, geometric mean PC(15)PtcO(2)MCH and atopic status. The median serum IgE level was significantly higher in AMP-responsive group than the non-responsive ones (p = 0.011). The peripheral blood eosinophilia was more frequent among responsive children (p = 0.019), and it was found as the only predictive factor for AMP responsiveness in preschool-age children with asthma in logistic regression model (odds ratio: 5.14; 95% CI: 1.23-21.47; p = 0.025). AMP responsiveness may be predicted by peripheral blood eosinophilia but not with atopy markers in young children with asthma.
authors.affiliation: Gazi University, Faculty of Medicine, Department of Pediatric Allergy and Asthma, Ankara, Turkey. arzub@gazi.edu.tr
authors.forename: Arzu
authors.initials: A
authors.lastname: Bakirtas
authors.forename: Ipek
authors.initials: I
authors.lastname: Turktas
mesh_terms: D000249:Adenosine Monophosphate; D001249:Asthma / Q000097:blood / Q000276:immunology / Q000503:physiopathology*; D001785:Blood Gas Monitoring, Transcutaneous; D016535:Bronchial Hyperreactivity / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D002675:Child, Preschool; D004804:Eosinophils / Q000276:immunology; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008297:Male; D016210:Methacholine Chloride; D012882:Skin Tests
chemical_list: D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride; D007073:Immunoglobulin E; D000249:Adenosine Monophosphate