Objectives To study the roles of Th17 cells in peripheral blood and the serum level of IL-17 in children with acute respiratory syncytial virus (RSV) bronchiolitis. Methods A total of 28 children with RSV bronchiolitis were selected as bronchiolitis group, among whom twelve cases were assigned into severe group and sixteen cases were assigned into mild group according to the severity of illness. Twelve cases with acute asthma were selected as asthma group. Ten children without recent infection waiting for surgery were chosen as controls. The percentage of Th17 cells in peripheral blood was measured by lfow cytometry. The serum level of IL-17 was detected by ELISA. The association of severity of illness with the percentage of Th17 cells and the level of IL-17 was studied in children with acute RSV bronchiolitis. Results The serum level of IL-17 and the percentage of Th17 cells were signiifcantly higher in the severe bronchiolitis group than those in the control group and mild bronchiolitis group (P<0.05). However, there was no signiifcant difference between the severe bronchiolitis group and the asthma group (P>0.05). Conclusions The percentage of Th17 cells and serum level of IL-17 are increased in children with acute RSV bronchiolitis, and may be involved in the pathogenesis of RSV bronchiolitis. (J Clin Pediatr,2013,31(9):850-853)

Objective To investigate the effects of leukotriene in children with respiratory syncytial (RSV)viral bronchiolitis.Methods The blood and sputum levels of Ieukotriene were detected in 33 cases diagnosed RSV bronchiolitis and 12 cases which were diagnosed pneumonia without RSV infection.Thirty-three cases of bronchiolitis were devided into mild-moderate group(n =22)and severe group(n =11)according to the lowell score.Results The blood and sputum levels of leukotriene in mild-moderate group,severe group,and pneumonia group were(76.96 ± 28.19)pg/ml,(103.53 ± 16.85)pg/ml,(18.14.± 7.49)pg/ml;(31.83 ± 19.14)pg/ml,(67.11 ± 15.11)pg/ml,(6.81 ± 2.90)pg/ml in acute period,and(36.04 ±16.38)pg/ml,(52.27 ± 17.03)pg/m l,(18.14 ± 7.49)pg/ml of serum in recovery period.There were significant differences among three groups(F =48.09,P ＜ 0.001 ; F =15.50,P ＜ 0.001 ; F =44.43,P ＜0.001).After treatment,the blood levels of leukotriene were significantly decreased,but were still higher than that of pneumonia group(P ＜ 0.05).Conclusion The blood and sputum levels of leukotriene increase in children with RSV bronchiolitis,which is related with the severity of bronchiolitis.