A Systematic Review And Meta-analysis On Efficacy And Safety Of Bacterial Lysatestherapyforchildhood Asthma

Background: Bronchial asthma is the most common respiratory allergic disease in childhood,which seriously affects the quality of life of children.Severe and critical asthma attacks even can endanger the lives of children.Inhaled glucocorticoid is an important first-line anti-inflammatory drug in the treatment of asthma,but it is still poorly controlled in some patients.Acute respiratory infection is one of the important risk factors.With the further research on the role of immune imbalance mechanism in childhood asthma,immunomodulator have been paid more and more attention.In recent years,more and more studies have discovered the immunomodulatory effects of bacterial lysates,which have been confirmed in some children’s allergic diseases.Objective: To evaluate the efficacy and safety of bacterial lysates in childhood asthma.Methods: We searched English and Chinese database(Pub Med,Medline,Embase,Cochrane Library,CNKI,Wan Fang Periodical Database and VIP Database)until January 2020 for randomized controlled trials(RCTs)that reported the use of bacterial lysates for childhood asthma.The bias risk was assessed using Cochrane Collaboration’s tool and the classification of evidence level was performed in accordance with the GRADE.Results: A total of 19 RCTs,including 1760 pediatric patients,were included for this systematic review and meta-analysis.The bacterial lysates showed a positive correlation with reducing frequency of asthmatic attacks(MD=-1.21,95%CI:-1.75～-0.67,P<0.0001),days of wheezing(MD=-2.86,95%CI:-4.57～-1.15,P=0.001),and frequency of respiratory infections(MD=-1.66,95%CI:-2.26～-1.06,P<0.00001)in comparison with the control group.The intervention group was also more effective than control groups in promoting level of pulmonary function index [FEV1(MD=0.17,95%CI: 0.12～0.21,P<0.00001),PEF(MD=0.43,95%CI:0.32～0.54,P<0.00001)and FVC(MD=0.21,95%CI:0.09～0.32,P=0.0003)],improving the effective rate of treatment(RR=1.45,95%CI: 1.20～ 1.74,P<0.0001)and increasing IL-10 level(MD=15.82,95%CI: 6.04～ 25.60,P=0.002);although adverse reaction rate in the intervention group increased(RR=1.74,95%CI: 1.11～2.72,P=0.02),they were all mild and transient reactions.Conclusion: This systematic review and meta-analysis reveals that bacterial lysates have a protective effect on childhood asthma,including improving clinical symptoms and enhancing lung function,and will not cause serious adverse reactions.However,most of the literature included in this study are of low quality,and the level of evidence is generally not high,which still needs to be verified by well-designed multicenter,large sample RCTs.