An Analysis of Virus Types and IL-4 Level after Bronchiolitis in Infan ts

Objective To evaluate the possible relati onship between virus types and the level of IL-4 after bronchiolitis.M ethods First,multiple respiratory viral antigens in nasopharyngeal se cretions from these infants with bronchiolitis were detected with immunofluoresc ence assay.Then,eighty cases with a history of bronchiolitis were divided into f our groups(respiratory syncytial virus group,adenovirus group,influenza virus gr oup and parainfluenza virus group) at random according to the virus they had inf ected.Finally,the level of IL-4 in serum of these cases was determined by ELISA before treatment,during recovery and three months later after recovery. Results Before treatment,the levels of IL-4 from these virus groups were significantly higher than that from control group(P0.01),during re covery,the levels of IL-4 from all groups showed no significantly difference(P 0.05).Three months later after recovery,the level of IL-4 from respiratory syncytial virus group 〔(72.8±21.3)ng/L〕 was significantly higher than tha t from the control group 〔(51.7±16.2)ng/L〕(P0.01),and higher than that from adenovirus group 〔(59.1±19.4)ng/L〕,influenza virus groups 〔( 57.5±19.5)ng/L〕 and parainfluenza virus group 〔(56.3±18.5)ng/L〕 also (P0.05).Conclusion The level of IL-4 increases agai n three months later after recovery in these infants with bronchiolitis infected by respiratory syncytial virus,which indicates that the respiratory syncytial v irus may modify Th 1/Th 2 imbalance,and leads to the development of asthma.