【作者】 陈光明；

【导师】 杨锡强；

【作者基本信息】 重庆医科大学 ， 儿科学， 2002， 博士

【摘要】 背景：先天性心脏病(congenital heart disease，CHD)患儿易伴发感染，传统观点认为其感染与血液动力学改变和机械因素有关，然而近期的文献显示：CHD可能是Digeorge综合征(Digeorge syndrome，DGS)的一部分，CHD患儿对感染的易感性与其存在不同程度的免疫功能缺陷有关。目的：探讨CHD患儿有无免疫功能缺陷，观察CHD新生儿胸腺影改变，了解CHD患儿是否存在甲状旁腺功能低下。结合文献探讨CHD与DGS的关系。方法：（一） 检测28例单纯性CHD患儿和20例对照组儿童（门诊体检的正常儿童）外周血部分免疫学指标：1 用单克隆抗体和流式细胞仪(FCM)检测淋巴细胞亚群的变化。用逆转录聚合酶链反应（reverse transcription and polymerase chain reaction，RT-PCR）半定量测定外周血单个核细胞（peripheral blood monoeuclear cell，PBMC）经植物血凝素（phytohaemagglutinin，PHA）诱导的白细胞介素4（interleukin-4，<WP=9>2 IL-4）和γ-干扰素（interferon-gamma，IFN-γ）mRNA表达，以单克隆抗体酶联免疫吸附法（enzyme-linked immuno-sorbent assay，ELISA）测定培养上清中IL-4和IFN-γ含量。3 用3H胸腺嘧啶核苷（3H-thymidine，3H-TdR）掺入法测定PBMC经PHA和脂多糖（lipopolysaccharide，LPS）诱导的增殖功能。4 用免疫散射比浊法（immuno-scatter turbidmetry，ISTM）测定血清免疫球蛋白和C3水平。（二）用胸部X光片回顾性测定72例单纯性心脏畸形CHD、34例复杂性心脏畸形CHD新生儿及50例对照组新生儿（同日龄肺炎新生儿）胸腺影的大小。（三）检测18例单纯性CHD患儿和17例对照组儿童（门诊体检的健康儿童）外周血清甲状旁腺素（parathyroid hormone，PTH）水平及离子Ca2+、Mg2+浓度。PTH用放射免疫法(immunoradiometric assay，IRMA)测定，离子Ca2+用离子选择电极法（ion selective electrode，ISE）测定，Mg2+用甲基麝香草酚蓝比色法(methyl thyme camphor blue，MTB)测定。结果：与对照组儿童比较，CHD患儿外周血总T细胞和CD8+T细胞数稍增高，CD4/CD8比值、NK细胞和B细胞数略降低，但无统计学意义，CD4+T细胞数与对照组儿童无差别。两组儿童的<WP=10>1 淋巴细胞亚群均随年龄的增加而有轻度改变，但各年龄段之间比较无统计学意义。各年龄段CHD患儿与同年龄段对照组患儿比较以上指标均无显著性差异。2 CHD患儿PBMC增殖功能正常，3H-TdR每分钟放射脉冲数（counts of per minut impulse，cpm值）和增殖指数（proliferative index，PI）与对照组儿童比较均无显著性差异。两组儿童的cpm值和PI均随年龄的增长略有改变，但各年龄段之间比较无统计学意义。各年龄段CHD患儿与同年龄段对照组儿童比较cpm值和PI均无显著性差异。3 与对照组儿童比较，CHD患儿PBMC IL-4mRNA表达稍低，IFN-γmRNA表达稍高，培养上清中IL-4水平稍低，IFN-γ水平稍高，但无统计学意义。两组儿童的IL-4mRNA表达和IL-4水平均随年龄增长略有降低，而IFN-γmRNA表达和IFN-γ水平均随年龄增长略有增高，但无统计学意义。各年龄段CHD患儿与同年龄段对照组儿童比较以上四个指标均无显著性差异。4 CHD患儿血清IgG和IgA水平较对照组略高，而IgM和C3较对照组略低，但无统计学意义。两组儿童的IgG水平随年龄的增加略有升高，IgM、IgA和C3水平随年龄变化亦略有改变，但同年龄段之间比较无统计学意义。各年龄段CHD患儿血清IgG、IgA、IgM及C3水平与同年龄段对照组儿童比较均无显著性差异。<WP=11>5 所有新生儿的X光片上均可见到胸腺影，目测结果形状多变，大小有异。单纯性心脏畸形CHD新生儿和复杂性心脏畸形CHD新生儿的胸腺影大小与同日龄肺炎新生儿比较均无显著性差异。6 CHD患儿血清PTH水平较对照组明显降低，二者比较有显著性差异(p<0.05)，CHD患儿有8例（44.4%）PTH<10ng/L，而对照组无一例<10ng/L；CHD患儿血清Ca2+和Mg2+较对照组稍低，但无统计学意义。结论：1 并非所有的CHD患儿均并发免疫功能缺陷。2 单纯的CHD可能不是DGS的一个部分，即使是DGS也可能属于部分性DGS(partial DGS，pDGS)而非完全性DGS(complete DGS，cDGS)，其免疫功能低下不明显。3 CHD患儿易感染不一定是先天性免疫功能低下的表现。4 CHD新生儿无胸腺的先天性发育不全。5 CHD患儿PTH分泌的储备不足，存在亚临床甲状旁腺功能低下。6 CHD患儿甲状旁腺功能低下可能是因合并部分的先天性甲状旁腺发育不良所致。更多还原

【Abstract】 Background：Children with congenital heart disease(CHD) are vulnerable for infections. The alteration of blood kinetic and mechanic factors are traditionally thought to be the cause，but literatures in the last years show that CHD may be a part of Digeorge syndrome(DGS) and that the susceptibility to infection in children with CHD may be related to partial primary immunodeficiency.Objective：To explore whether there is immunodeficiency in children with CHD in terms of measurement of thymus shadow on X-ray film during neonate stage，the immunologic and parathroid functions in the early childhood were observed and to clarify the relationship between CHD and DGS by reviewing literatures.Methods：1 Partial immunologic laboratory data from peripheral blood were observed in 28 children with simple CHD and 20 age matched healthy children servered as a control.1.1 Classification of lymphocytic subsets measured by monoclone<WP=13>antibodies and flow cytometer.1.2 The mRNA expression of IL-4 and IFN-γin peripheral blood monoeuclear cell（PBMC） stimulated with phytohaemagglutinin(PHA)and the levels of IL-4 and IFN-γin supernatant were measured by reverse transcription and polymerase chain reaction(RT-PCR) and enzyme-linked immuno-sorbent assay(ELISA) respectively. 1.3 The proliferative response of PBMC stimulated with PHA and lipopolysaccharide(LPS) were measured by intake of 3H-thymidine(3H-TdR) technique.1.4 Serum IgG、IgA、IgM and C3 levels were estimated by immune scatter turbidimetry.2 The size of thymus shadow of chest X ray films in 106 neonates including 74 simple and 34 complex CHD were measured retrospectively.50 neonates with pneumonia enrolled in the control.3 The serum parathyrin(PTH)、Ca2+ and Mg2 in 18 children with simple CHD and 17 age matched healthy children were estimated by immunoradiometric assay(IRMA),ion selective electrode(ISE) and methyl thyme camphor blue(MTB) respectively.Results：<WP=14>1 The amount of total T and CD8+T lymphocytes was higher and the ratio of CD4/CD8, the amount of NK cells and total B cells were lower in children with CHD as compared with control，but no significant statistic difference was found. The number of CD4+T lymphocytes in both CHD and control was the same. The peripheral blood lymphocytic subsets in children with CHD and control were changed along with age increasing，but no significant statistic difference.2 Comparing with normal control, proliferative response of PBMC stimulated with PHA and LPS in children with CHD was normal.3 The IL-4mRNA expression in PBMC and the levels of IL-4 in supernatants of PBMC were lower gently，IFN-γmRNA expression in PBMC and the levels of IFN-γ in supernatants of PBMC were higher gently in children with CHD as compared with controls，but there were no significant statistic differences.4 The serum levels of IgG and IgA in CHD children were higher，and IgM and complement C3 were lower than those in controls，.but no significant differences were found. The levels of IgG rised gently as their age increased in both groups，but no significant statistic difference were found.<WP=15>5 The thymus shadow of X-ray film was found in all neonates both CHD and controls with variance in shape and size. The sizes of thumus shadow for simple and complex CHD were no different.6 The serum levels of PTH in children with CHD were significantly lower as compared with controls. The level of PTH below 10ng/L was found in 8 cases in CHD group，but none of the controls.The serum concentration of Ca2+ and Mg2+ was mildly decreased in CHD group in comparation with controls，but there were no statistic significance.Conclusion：1 Immunodeficiency does not exist in children with CHD enrolled in this study.2 Simple CHD probably is not a part of DGS. Even if it belongs to DGS，it would not be complete DGS(cDGS), may be partial DGS(pDGS)，without significant immunodeficiency.3 It is unlikely that children with CHD tending to pulmonary infection is caused by primary immunode更多还原