髓样分化因子88的表达变化在新生儿窒息后多器官功能障碍综合征的意义

目的:研究窒息新生儿外周血单个核细胞(Peripheral blood monocytes,PBMCs)髓样分化因子88(Myeloid dif-ferentiation factor88,MyD88)的表达变化与新生儿窒息后多器官功能障碍综合征(Multiple organ dysfunction syndrome,MODS)的关系及其与病情预后的关系。方法:窒息后24h之内入院的足月新生儿50例,采集生后第1天及第3、7天的外周血及10例正常健康足月新生儿的外周血,分离单个核细胞。用免疫组化的方法检测单核细胞内MyD88的表达情况。所有新生儿均常规进行经皮血氧饱和度和心电监测3天,同时作血肝功、肾功、心肌酶、电解质、血常规、尿常规、血气分析及心电图和头颅CT等检查,结合临床表现统计窒息后全身炎症反应综合征(Systemic inflammmory response syndrome,SIRS)和MODS的发生情况及其疾病的转归情况。结果:①新生儿窒息后SIRS的发生率是80%,轻度窒息组有71%发生了SIRS,重度窒息组有91%发生了SIRS。MODS的发生率是72%,轻度窒息组有61%发生MODS,重度窒息组有86%发生MODS。50例窒息新生儿有46例治愈出院,2例病情危重放弃治疗,2例抢救无效死亡。②正常健康足月新生儿的单个核细胞MyD88的表达比较弱。窒息新生儿单个核细胞内的MyD88在窒息后第1天的表达增强,3天开始减弱,7天左右恢复正常。③在窒息后第1天,MyD88表达与新生儿危重症评分呈显著负相关关系(r=-0.73,P<0.01),与SIRS和MODS的发生率呈显著正相关关系;发生了SIRS和MODS的病例,其MyD88的表达呈(++)～(+++)的比例增多,差异具有统计学意义(P<0.01);预后差的病例,MyD88的表达呈(++)～(+++)的比例增多,差异具有统计学意义(P<0.05)。结论:新生儿窒息后SIRS和MODS的发生率都很高,窒息早期可能激活了Toll样受体转导通路中的转载分子MyD88,引起单核-巨噬细胞系统释放一系列炎症因子导致了SIRS和MODS的发生。MyD88可以作为诊断新生儿窒息后SIRS和MODS的早期指标和估计预后的指标之一。

The significance of the expression of myeloid differentiation factor 88 in multiple organ dysfunction syndrome induced by neonatal asphyxia

Objective:To investigate the relationship between the expression of myeloid differentiation factor 88(MyD88) in peripheral blood monocytes(PBMCs) and multiple organ dysfunction syndrome(MODS) in asphyxiated neonates.Methods:50 asphyxiated neonates admitted hospital within 24 hours after their birth and 10 normal neonates were enrolled in this study,their peripheral blood were collected to segregate monocytes for detecting the expression of MyD88 by immunohistochemical method on the first day,the third day and the seventh day.At the same time,all neonates' transcutaneous oxygen saturation and electrocardiogram were monitored for 3 days,and their hepatic functions,renal functions,myocardial enzymes,electrolytes,blood counts,urinalysis,blood gas analysis,electrocardiogram and CT scans were tested.The incidence and the prognosis of SIRS and MODS in those asphyxiated neonates were assessed.Results:①The total incidence of SIRS in those asphyxiated neonates was 80%:71% in mild asphyxia group and 91% in severe asphyxia group;the incidence of MODS was 72%:61% in mild asphyxia group and 86% in severe asphyxia group.Among those asphyxiated neonates,46 c were cured,2 neonates were given up,and 2 neonates were dead.②The expression of MyD88 was very little in normal neonates,while it was strong in asphyxiated neonates on the first day,then began to decrease on the third day,finally became normal on the seventh day.③There was a negative correlation between the expression of MyD88 and the score of neonatal critical degree(γ=-0.73,P<0.01) on the first day of asphyxia,and was positively correlated with the incidence of SIRS and MODS.In the neonates with SIRS and MODS,the ratio of MyD88 expression was++～+++ rises(P<0.01),in the neonates with bad prognosis,the ratio of MyD88 expression was ++～+++ rises(P<0.05).Conclusion:The incidences of SIRS and MODS are very high in asphyxiated neonates,it is related to the activation of MyD88 in PBMCs,which can induce mononuclear macrophage to release inflammatory factors,then SIRS and MODS occurred.The expression of MyD88 in PBMCs can be regarded as an early index in the diagnosis and estimate prognosis of SIRS and MODS in asphyxiated neonates.