周　琴　张　勤　周素芽.浙江省人民医院儿科，浙江杭州　3004；.杭州市儿童医院新生儿科，浙江杭州　30006

TLR4在晚发型新生儿败血症中的意义

周琴1张勤1周素芽2
1.浙江省人民医院儿科，浙江杭州310014；2.杭州市儿童医院新生儿科，浙江杭州310006

目的探讨Toll样受体4（TLR4）对晚发型新生儿败血症诊断的临床意义。方法选取2011年8月～2014年11月我院收治的血培养阳性的新生儿38例作为败血症组，根据感染病原体将其分为革兰阳性菌感染组（G+组）23例，革兰阴性菌感染组（G-组）15例，另选取我院同期收治的无感染性疾病的新生儿20例作为对照组，采集各组患儿外周血，应用密度梯度离心法分离出外周血单个核细胞，采用RT-PCR法检测TLR4 mRNA表达水平，免疫投射比浊法检测血清CRP水平。比较组间各指标的差异，并分析两者的相关性。结果 G+组与G-组TLR4 mRNA及CRP水平与对照组相比均明显升高（P<0.01）；CRP在G+组与G-组两组间差异无统计学意义（P>0.05）；G-组TLR4 mRNA的表达明显高于G+组（P<0.05）。TLR4与CRP呈正相关（r=0.749，P＜0.01）。结论TLR4可以作为诊断晚发型新生儿败血症的有效指标，尤其对于识别革兰阴性菌感染更有意义。

Toll样受体4；C反应蛋白；新生儿；败血症

[Abstract]Objective To investigate the clinical significance of toll-like receptor 4(TLR4)in the diagnosis of late-onset neonatal septicemia.Methods A total of 38 newborns with positive blood culture who were admitted from August 2011 to November 2014 were selected as the septicemia group.According to the infection pathogens,the newborns were divided into gram positive bacteria infection group(G+)with 23 cases,gram negative bacteria infection group(G-)with 15 cases and 20 newborns without infectious diseases from the same period of time were selected as the control group. The peripheral blood of the newborns was collected and peripheral blood mononuclear cells were isolated with the density gradient centrifugation.The expression level of TLR4 mRNA was detected with RT-PCR method and serum CRP level was detected with immunity transmission turbidity.Compare the differences of each index of the two groups and analyze the correlation of the two groups.Results G+group and G-group both had significant higher TLR4 mRNA and CRP level compared with that of the control group(P<0.05);the difference of CRP level of the G+group and G-group had no statistical significance(P>0.05);the TLR4 mRNA level of G-group was significantly higher than that of the G+group(P<0.05).TLR4 and CRP had positive correlation(r=0.749,P<0.01).Conclusion TLR4 can be taken as the effective index in the diagnosis of late-onset neonatal septicemia,especially for the identification of G+infection.

[Key words]Toll-like receptor 4;C-reactive protein;Newborn;Septicemia

新生儿免疫系统未成熟，免疫功能较差，极易发生细菌感染，发生感染后很难局限而导致败血症[1]。新生儿败血症早期临床表现不典型，病情发展迅速，是新生儿死亡的重要原因[2]，因此选取敏感性、特异性高的指标对新生儿败血症的早期诊断具有非常重要的意义。虽然C反应蛋白（C-reaction protein，CRP）是新生儿败血症经典的指标之一，但其仍缺乏一定的特异性[3]。Toll样受体4（Toll-like receptor 4，TLR4）是连接天然免疫和获得性免疫的桥梁，可与病原识别模式分子结合，通过介导细胞信号转导致炎症因子释放，从而识别病原微生物、启动炎症应答[4]。……