哮喘合并肺炎支原体感染患儿血清CD4^(+)/CD8^(+)、IL-5、维生素D对肺功能的影响

Effects of serum levels of CD4^(+)/CD8^(+),interleukin-5 and vitamin D on pulmonary function of children with asthma complicated with mycoplasma pneumonia infection

目的探讨哮喘合并肺炎支原体(MP)感染患儿血清CD4^(+)/CD8^(+)、白细胞介素-5(IL-5)、维生素D水平对肺功能的影响。方法选取2019年7月至2021年7月西部战区总医院儿科收治的哮喘患儿120例,根据是否感染MP将其分为感染组69例与未感染组51例,另外纳入同期体检健康儿童40例作为对照组。比较三组的T淋巴细胞亚群检测结果及免疫球蛋白G(IgG)、IL-5、维生素D、超敏C反应蛋白(hs-CRP)水平,以及肺功能指标[用力肺活量(FVC)、潮气量(Vt)、潮气呼气峰流速(PTEF)]。利用Pearson法分析MP感染患儿的CD4^(+)/CD8^(+)、IL-5、IgG、维生素D、hs-CRP与肺功能指标的相关性。结果(1)三组小儿的CD4^(+)T、CD8^(+)T、CD4^(+)/CD8^(+)及IgG水平比较差异均有统计学意义(F值分别为141.053、117.220、242.024、619.257,P<0.05);感染组和未感染组的CD4^(+)T、CD4^(+)/CD8^(+)比值均明显低于对照组,而CD8^(+)T、IgG水平均明显高于对照组,感染组的CD4^(+)T、CD4^(+)/CD8^(+)比值均明显低于未感染组,而CD8^(+)T、IgG水平均明显高于未感染组,差异均有统计学意义(t=4.450~30.419,P<0.05)。(2)三组小儿的IL-5、维生素D、hs-CRP水平比较差异均有统计学意义(F值分别为304.313、90.464、124.196,P<0.05);感染组和未感染组的维生素D水平均明显低于对照组,而IL-5、hs-CRP水平均明显高于对照组,感染组的维生素D水平明显低于未感染组,而IL-5、hs-CRP水平均明显高于未感染组,差异均有统计学意义(t=5.632~25.103,P<0.05)。(3)三组小儿的FVC、Vt和PTEF水平比较差异均有统计学意义(F值分别为47.175、34.759、25.371,P<0.05);感染组和未感染组的FVC、Vt、PTEF水平均明显低于对照组,感染组的FVC、Vt和PTEF水平均明显低于未感染组,差异均有统计学意义(t=3.142~10.955,P<0.05)。(4)哮喘合并MP患儿的CD4^(+)/CD8^(+)和维生素D分别与FVC、Vt和PTEF呈正相关(r=0.323~0.670,P<0.05),而IL-5和IgG及hs-CRP分别与FVC、Vt、PTEF呈负相关(r=-0.682~-0.397,P<0.05)。结论MP感染可能导致哮喘患儿维生素D缺乏、IL-5上调、CD4^(+)/CD8^(+)比值下降,影响患儿肺功能,临床治疗哮喘时应加强对MP感染的控制。

Objective To explore effects of serum levels of CD4^(+)/CD8^(+),interleukin-5(IL-5)and vitamin D on pulmonary function of children with asthma complicated with mycoplasma pneumonia(MP)infection.Methods A total of 120 children with asthma who admitted to Department of Pediatrics of our hospital from July,2019 to July,2021 were enrolled.According to presence or absence of MP antibody,the children were divided into MP infection group and non-MP infection group.40 healthy children who received physical examination in the same period were enrolled as control group.The serum levels of T lymphocyte subsets,immunoglobulin G(IgG),interleukin-5(IL-5),vitamin D,high-sensitivity C-reactive protein(hs-CRP)and pulmonary function parameters[forced vital capacity(FVC),tidal volume(Vt),tidal peak expiratory flow rate(PTEF)]of all children were compared among the three groups.Pearson correlation analysis method was used to analyze correlations of serum levels of CD4^(+)/CD8^(+),IL-5,vitamin D with pulmonary function parameters.Results(1)There were significant differences in serum levels of CD4^(+)T,CD8^(+)T,CD4^(+)/CD8^(+)and IgG of the children among the three groups(F=141.053,117.220,242.024 and 619.257 respectively,all P<0.05).The serum levels of CD4^(+)T and CD4^(+)/CD8^(+)of the children in the MP infection group and the non-MP infection group were significantly lower than those in the control group,while the serum levels of CD8^(+)T and Ig-G were significantly higher than those in the control group.As well,the serum levels of CD4^(+)T and CD4^(+)/CD8^(+)of the children in the MP infection group were significantly lower than those in the non-MP infection group,while the serum levels of CD8^(+)T and Ig-G were significantly higher than those in the non-MP infection group,and the differences were significant(t=4.450-30.419,all P<0.05).(2)There were significant differences in serum levels of IL-5,vitamin D and hs-CRP of the children among the three groups(F=304.313,90.464 and 124.196 respectively,all P<0.05).The serum level of vitamin D of the children in the MP infection group and the non-MP infection group was significantly lower than that in the control group,while the serum levels of IL-5 and hs-CRP of the children in the MP infection group and the non-MP infection group were significantly higher than those in the control group.As well,the serum level of vitamin D of the children in the MP infection group was significantly lower than that in the non-MP infection group,while the serum levels of IL-5 and hs-CRP were significantly higher than those in the non-MP infection group,and the differences were significant(t=5.632-25.103,all P<0.05).(3)There were significant differences in FVC,Vt and PTEF of the children among the three groups(F=47.175,34.759 and 25.371 respectively,all P<0.05).The FVC,Vt and PTEF of the children in the MP infection group and the non-MP infection group were significantly lower than those in the control group.As well,the FVC,Vt and PTEF of the children in the MP infection group were significantly lower than those in the non-MP infection group,and the differences were significant(t=3.142-10.955,all P<0.05).(4)The serum levels of CD4^(+)/CD8^(+)and vitamin D were positively correlated with FVC,Vt and PTEF(r=0.323-0.670,all P<0.05),while the serum levels of IL-5,IgG and hs-CRP were negatively correlated with FVC,Vt and PTEF(r=-0.559,-0.415,-0.682,-0.486,-0.504,-0.397,-0.602,-0.478 and-0.511 respectively,all P<0.05).Conclusion MP infection may lead to vitamin D deficiency,up-regulation of IL-5 and decrease in CD4^(+)/CD8^(+)level in asthmatic children,which may affect pulmonary function of the patients.Therefore,in clinical treatment of asthma,controlling MP infection should be strengthened.