RT Journal Article SR Electronic T1 Gene expression of inflammatory markers in wheezing preschool children; the ADEM study JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p3289 VO 38 IS Suppl 55 A1 Ester M.M. Klaassen A1 Kim D.G. van de Kant A1 John Penders A1 Gertjan M. den Hartog A1 Shufan Qi A1 Quirijn Jöbsis A1 Onno C.P. van Schayck A1 Gerard H. Koppelman A1 Guillaume van Eys A1 Edward Dompeling YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p3289.abstract AB Background: Wheeze affects 20-40% of preschool children. Of all wheezers 30% will have persisting symptoms after the age of six that develop into asthma which is characterized by chronic airway inflammation. Whether airway inflammation is a characteristic of preschool wheezing is poorly documented.Aim: To assess cross-sectional differences in gene expression of several important inflammatory markers in venous blood cells in preschool children with recurrent wheeze compared to healthy controls.Methods: In total, 202 children with recurrent wheeze (ISAAC questionnaire ≥2 wheezing episodes) and 50 children without respiratory symptoms, age 2-3 year were selected. Total RNA was extracted from peripheral blood mononuclear cells. Gene expression of 21 genes was assessed and corrected for geometric mean of 3 housekeeping genes. Both unadjusted and adjusted (controlling for age, gender, passive smoking and pet exposure) logistic regression analysis was subsequently conducted.Results: Gene expression was successfully analysed in 223 children. Expression of the catalase gene (CAT) showed a statistically significant inverse association with recurrent wheeze (ORadjusted 0.65 (0.48-0.88) p=0.005). Expression of interleukin-17 (IL17) showed a statistically significant positive association with recurrent wheeze (ORadjusted 3.04 (1.33-6.92) p=0.008). None of the other genes showed a significant relationship between gene expression level and recurrent wheeze.Discussion: A decrease of CAT expression and an increase of IL17 expression was observed in preschool children with recurrent wheeze. This may point towards the importance of different inflammatory pathways in children with preschool wheezing.