Clinical study on bacille calmette-guerin alone or combined with interferon gamma and vitamin A in preventing asthma children after bronchiolitis

Objective To discuss the effects of bacille calmette guerin(BCG) alone of combined with interferon gamma(IFN-γ) and vitamin A in preventing asthma after bronchiolitis.Methods Fourty-four bronchiolitis infants(RBI) were treated with BCG alone or combined with vitamin A/IFN-γ.Protein purified derivative(PPD) skin test were observed before and 3 months after interference and all infants enrolled in the study were followed up for average one year to observe the wheezing episodes. Ninteen cases of RBI without BCG treatment were control group.Results The average diameter of PPD skin test in RBI after BCG inoculation was significantly larger than that of before inoculation and control group(P0.005,0.05) respectively,and infants treated with BCG inoculation combined with IFN-γ/vitamin A more effective (P0.05 ).The frequency and persistence of wheezing was lower in interfered infants with acute bronchiolitis either by BCG alone or BCG combined with IFN-γ/vit A than that of control group in 1 year(χ2=6.97 P0.05), but no obvious difference exists between the group used BCG alone and the group used BCG combined with vitamin A/IFN-γ(P0.05).Conclusions BCG inoculation can enhance the positive diverson rate of the PPD skin tests and prevent recurrent wheezing after acute bronchiolitis. Vitamin A and IFN-γ have some synergism with BCG.