12岁以下儿童肺炎支原体感染后分类抗体变化趋势分析

Analysis of the variation trend of classified antibodies after Mycoplasma pneumoniae infection in children under 12 years old

目的 探讨12岁以下儿童肺炎支原体(Mycoplasma pneumoniae,MP)感染后体内IgM和IgG抗体变化趋势,为临床诊治该病提供科学依据。方法 选择2017年1月至2019年12月某医院就诊的MP感染患儿240例,其中肺炎支原体肺炎(Mycoplasma pneumoniae pneumonia, MPP)100例和难治性肺炎支原体肺炎(refractory Mycoplasma pneumoniae pneumonia, RMPP)140例,根据年龄分为0~<3岁组、3~<6岁组、6~<9岁组、9~<12岁组,动态检测MP感染患儿不同时间的体内IgM和IgG抗体水平。结果 0~7d IgM和IgG的抗体阳性率分别为65.2%和50.5%,8~15d IgM抗体阳性率高达100.0%,IgG抗体阳性率为85.2%,16~30d IgM抗体阳性率逐渐降低,IgG抗体阳性率高达100.0%,随后抗体阳性率开始逐渐降低,维持在80.0%;MPP和RMPP组30d内IgM和IgG抗体水平逐渐升高,30d后开始下降,RMPP患儿30d内IgM抗体水平低,而RMPP患儿在发病31~180d的IgG抗体水平较MPP患儿更高,差异有统计学意义(Z=3.324、3.422、2.876,P<0.001);与其他年龄组(0~<3岁组和9~<12岁组)相比,学龄前期儿童和学龄期儿童IgM抗体水平最低,发病31~180d,学龄前期儿童和学龄期儿童IgG抗体水平明显高于其他年龄组,差异有统计学意义(Z=3.021、2.211、2.569,P<0.001)。结论 MP感染的特异性IgM和IgG抗体水平随时间变化呈先上升后下降趋势,RMPP患儿特异性IgG抗体更明显,尤其是学龄前期儿童和学龄期儿童。

Objective To investigate the variation trend of IgM and IgG antibodies in children under 12 years old after Mycoplasma pneumoniae(MP)infection,and to provide scientific basis for clinical diagnosis and treatment of the disease.Methods A total of 240 cases of children with MP infection who attended a hospital from January 2017 to December 2019 were selected,including 100 cases of Mycoplasma pneumoniae pneumonia(MPP)and 140 cases of refractory Mycoplasma pneumoniae pneumonia(RMPP).According to the age,they were divided into groups of O to<3 years old,3 to<6 years old,6 to<9 years old,and 9 to<12 years old.The levels of IgM and IgG antibodies were dynamically detected at different time points in the children infected with MP.Results The positive rates of IgM and IgG antibodies were 65.2%and 50.5%in 0 to 7 days,respectively.The positive rates of IgM and IgG antibodies were 100.0%and 85.2%in 8 to 15 days.The positive rate of IgM antibody gradually decreased in 16 to 30 days,and the positive rate of IgG antibody was as high as 100.0%,and then the positive rate began to gradually decrease and maintained at a positive level of 80.0%.In the MPP and RMPP groups,IgM and IgG antibody levels gradually increased within 30 days and began to decrease after 30 days.The IgM antibody levels were low within 30 days in children with RMPP,while the IgG antibody levels were higher in children with RMPP patients than that in children with MPP from 31 to 180 days after onset,and the differences were statistically significant(Z=3.324,3.422 and 2.876,P<0.001).Compared with other age groups(0 to<3 years old group and 9 to<12 years old group),IgM antibody levels were lowest in pre-school age and school-age children.IgG antibody levels were significantly higher in pre-school age and school-age children than those in other age groups from 31 to 180 days after onset,and the differences were statistically significant(Z=3.021,2.211,and 2.569,P<0.001).Conclusion The levels of specific IgM and IgG antibodies of MP infections tend to increase first and then decrease with time variation,and the specific IgG antibodies are more obvious in children with RMPP,