目的:了解婴幼儿急性下呼吸道感染和支气管哮喘抗肺炎支原体、肺炎衣原体和RSV抗体水平。方法:采用回顾性分析方法,将接受间接免疫荧光法检测的急性下呼吸道感染和支气管哮喘的婴幼儿患儿120例和对照组100例无相关呼吸道疾病婴幼儿的血清抗肺炎支原体(MP)抗体、抗肺炎衣原体(CP)抗体和抗呼吸道合胞病毒(RSV)抗体检测结果进行对比分析。结果:①观察组血清抗MP抗体阳性率最高,为35.83%,抗CP抗体阳性率最低,为22.50%,与对照组相比差异有统计学意义(χ2=14.78,P<0.05;χ2=7.22,P<0.05)。②婴幼儿患儿各年龄段中MP IgM、CP IgM和RSV IgM分布情况,血清MP IgM和CP IgM阳性率在1~3岁组最高,RSVIgM阳性率30天~1岁组中最高。③抗RSV抗体在支气管哮喘中阳性率最高分别为55.56%,抗MP抗体阳性率在非典型肺炎中最高,为46.27%。④观察组患儿MP抗体、抗CP抗体和抗RSV抗体检测,单项指标的临床诊断实验评价抗MP抗体的敏感性和真实性最高,分别为37.66%和54.00%。结论:抗MP抗体、抗CP抗体和抗RSV抗体的检测是诊断婴幼儿急性下呼吸道感染和支气管哮喘中重要的参考指标,对病因诊断和治疗均有重要意义。 OBJECTIVE: To understand the levels of anti-Mycoplasma pneumoniae, Chlamydia pneumoniae and RSV antibodies in acute lower respiratory tract infection and bronchial asthma in infants and young children. Methods: A retrospective analysis was conducted in 120 infants and toddlers with acute lower respiratory tract infection and bronchial asthma who underwent indirect immunofluorescence assay, and 100 controls with no respiratory diseases related to serum anti-Mycoplasma pneumoniae (MP) antibody , Anti-Chlamydia pneumoniae (CP) antibodies and anti-respiratory syncytial virus (RSV) antibody test results were compared. Results: ① The positive rate of anti-MP antibody in observation group was the highest (35.83%), the lowest was anti-CP antibody (22.50%), the difference was statistically significant compared with control group (χ2 = 14.78, P < , P <0.05). ② The distribution of MP IgM, CP IgM and RSV IgM in infants and young children were the highest in 1 ~ 3 years old group, and the highest positive rate of RSVIgM was in 30 days ~ 1 year old group. ③ The highest positive rate of anti-RSV antibodies in bronchial asthma was 55.56%, the highest positive rate of anti-MP antibodies in atypical pneumonia was 46.27%. In the observation group, the detection of MP antibodies, anti-CP antibodies and anti-RSV antibodies in children in the observation group was the highest. The sensitivity and authenticity of the anti-MP antibodies in the clinical diagnosis of single index were the highest, 37.66% and 54.00% respectively. Conclusion: The detection of anti-MP antibody, anti-CP antibody and anti-RSV antibody is an important reference for diagnosis of acute lower respiratory tract infection and bronchial asthma in infants and young children. It is of great significance for the diagnosis and treatment of etiology.