Abstract: Objective To investigate the serum levels of 25-(OH)D₃, humoral immunity and cellular immunity in children with severe and mild pneumonia, and to explore the correlation among serum 25-(OH)D₃ level,the severity and immune function of community-acquired pneumonia (CAP) in children. Methods A total of 175 CAP patients were enrolled in Children′s Hospital Affiliated to Capital Institute of Pediatrics from March 2016 to March 2017,and were divided into severe pneumonia group(n=87) and mild pneumonia group(n=88).Also,100 healthy children whoperformed health examination in this hospital were selected as control group by random number method.The levels of serum 25-(OH)D₃, white blood cell count, neutrophil and lymphocyte ratio, C-reactive protein(CRP),procalcitonin(PCT), humoral immunity (IgA, IgG, IgM), and cellular immunity(CD4, CD8, CD19, CD16/56) were measured.And the correlations among serum 25-(OH)D₃ level, inflammatory cells and immune function were analyzed. Results The levels of serum 25-(OH)D₃ were significantly different among severe pneumonia group,mild pneumonia group and control group(F=76.95, P<0.05).There were significant differences on the white blood cell count, CRP, PCT and IgG levels between severe pneumonia group and mild pneumonia group(all P<0.05).Pearson analysis indicated that serum 25-(OH)D₃ level was negatively correlated with total white blood cell count(r=-0.307, P<0.05).Multifactor analysis showed that 25-(OH) D₃ and IgG levels were the risk factors of severe community-acquired pneumonia in children. Conclusions Serum 25-(OH)D₃ and IgG levels are associated with CAP in children.The levels of serum 25-(OH)D₃ and IgG in children with severe pneumonia are significantly lower than those in mild pneumonia group.So it is of great significance to test serum levels of 25-(OH)D₃ and IgG for early assessment of pneumonia.

Key words: community-acquired pneumonia, severe pneumonia, 25-(OH)D₃ , IgG

摘要： 目的 分析不同严重程度肺炎的患儿25-羟维生素D₃[25-(OH)D₃]、体液免疫及细胞免疫水平,研究血清25-(OH)D₃水平与儿童社区获得性肺炎(CAP)严重程度及免疫功能的相关性。方法 收集2016年3月-2017年3月在首都儿科研究所附属儿童医院收治的175例CAP患儿作为病例组,根据病情严重程度分为重症肺炎组(n=87),轻症肺炎组(n=88)。同期采用随机数字法收集在本院保健科进行健康体检的100例健康儿童作为对照组。测定3组儿童的血清25-(OH)D₃水平,同时检测所有肺炎组患儿白细胞计数、中性粒细胞及淋巴细胞比例、血浆C反应蛋白(CRP)、降钙素原(PCT)、体液免疫(IgA、IgG、IgM),细胞免疫(CD4、CD8、CD19、CD16/56)水平,并分析血清25-(OH)D₃水平与炎性细胞及免疫功能之间的相关性。结果 重症肺炎组、轻症肺炎组和对照组血清25-(OH)D₃水平差异有统计学意义(F＝76.95,P<0.05),轻、重症肺炎组间白细胞计数、CRP、PCT、IgG比较差异有统计学意义(P均<0.05)。Pearson相关分析结果显示血清25-(OH)D₃水平与白细胞总数呈负相关(r=-0.307,P<0.05)。多因素Logistic回归分析显示,25-(OH)D₃和IgG水平是儿童重症社区获得性肺炎的高危因素。结论 血清25-(OH)D₃与IgG水平与儿童社区获得性肺炎病情严重程度关系密切,重症肺炎患儿血清25-(OH)D₃与IgG水平明显低于轻症肺炎组,检测患儿的血清25-(OH)D₃和IgG水平对于疾病的早期评估有重要的意义。

关键词: 社区获得性肺炎, 重症肺炎, 25-羟维生素D₃, IgG