血清白细胞介素-6水平与极低出生体重儿脑白质损伤的关系

Value of serum interleukin-6 level in predicting white matter damage in very and extremely low birth weight infants

目的 探讨出生后早期血清白细胞介素-6（interleukin-6,IL-6）水平预测早产极低出生体重儿和超低出生体重儿脑白质损伤的价值. 方法 选择2012年6月至201 3年6月在华中科技大学同济医学院附属同济医院儿科住院的早产极低出生体重儿和超低出生体重儿共98例,根据头颅影像学结果将患儿分为脑白质损伤组46例和无脑白质损伤组52例.采用酶联免疫吸附试验检测患儿生后1h内和7d时的血清IL-6水平.采用两独立样本t检验、x2检验及Wilcoxon秩和检验进行统计学分析.采用受试者工作特性曲线分析血清IL-6水平预测早产儿脑白质损伤的敏感性和特异性. 结果 98例早产儿出生胎龄平均为（29.8±1.8）周（26～34周）;出生体重平均为（1 261±162）g（780～1 490g）.脑白质损伤组宫内感染、接受气管插管-肺表面活性物质-拔管治疗、Ⅰ～Ⅱ级和Ⅲ～Ⅳ级脑室周围-脑室内出血的比例分别为56.5％（26/46）、67.4％（31/46）、60.9％（28/46）和28.3％（13/46）,均高于无脑白质损伤组[分别为19.2％（10/52）、32.7％（17/52）、34.6％（18/52）和11.5％（6/52）,x2值分别为14.605、11.760、6.755和4.367,P值均＜0.05];5 min Apgar评分低于无脑白质损伤组[（4.6±2.1）分与（6.2±1.5）分,t=1.983,P=0.000].脑白质损伤组新生儿生后1h内血清IL-6水平明显高于无脑白质损伤组[130.7 pg/ml（38.2～1 020.0 pg/ml）与46.3 pg/ml（13.6～336.0 pg/ml）,Z=-6.929,P=0.000],生后7d时,2组差异无统计学意义[18.2 pg/ml（3.0～231.0 pg/ml）与16.4 pg/ml（1.0～121.0 pg/ml）,Z=-0.246,P=0.806].以55.0 pg/ml作为界值,生后1h内血清IL-6水平预测早产儿脑白质损伤的敏感性和特异性分别为93.5％和72.3％,曲线下面积为0.907（95％CI：0.844～0.970,P=0.000）. 结论 生后1h内血清IL-6水平可用于预测早产极低出生体重儿和超低出生体重儿脑白质损伤的发生风险.

Objective To investigate the value of serum interleukin-6 （IL-6） level in predicting white matter injury in preterm very low birth weight infants （VLBWI） and extremely low birth weight infants （ELBWI）.Methods Totally,98 VLBWI and ELBWI were admitted to Tongji Hospital between June 2012 and June 2013,and were divided into two groups according to the neuroimaging findings：46 infants with white matter injury as white matter injury group and 52 infants without white matter injury as control group.Serum IL-6 levels within one hour and at day 7 after birth were detected by enzyme-linked immunosorbent assay.Receiver operating characteristic curve was used to analyze the sensitivity and specificity of serum IL-6 levels in predicting white matter injury.Two-sample t test,Chi-square test and Wilcoxon rank sum test were used for statistical analysis.Results The mean gestational age and mean birth weight of all infants were （29.8± 1.8） weeks （26-34 weeks） and （1 261 ±162） g （780-1 490 g）.Compared with the control group,the white matter injury group infants had lower 5 min Apgar score （4.6±2.1 vs 6.2± 1.5,t=1.983） and higher incidence of intrauterine infection [56.5％ （26/46） vs 19.2％ （10/52）,x2=14.605],intubation-surfactantextubation [67.4％ （31/46） vs 32.7％ （17/52）,x2=11.760],and Ⅰ-Ⅱ and Ⅲ-Ⅳ grade of periventricularintraventricular hemorrhage [60.9％ （28/46） vs 34.6％ （18/52）,x2=6.755; 28.3％ （13/46） vs 11.5％ （6/52）,x2=4.367; all P＜0.05].The serum IL-6 levels within one hour after birth were significantly increased in the white matter injury group compared with the control group [130.7 pg/ml （38.2-1 020.0 pg/ml） vs 46.3 pg/ml （13.6-336.0 pg/ml）,Z=-6.929,P=0.000].Receiver operating characteristic curve showed that,if the cut-off point of serum IL-6 level was 55.0 pg/ml,the sensitivity and specificity of IL-6 within one hour after birth were 93.5％ and 72.3％,respectively,in predicting white matter injury in VLBWI and ELBWI,with the area under the curve of 0.907 （95％CI：0.844-0.970,P=0.000）.There were no significant differences of IL-6 levels between the two groups at day 7 after birth [18.2 pg/ml （3.0-231.0 pg/ml） vs 16.4 pg/ml （1.0-121.0 pg/ml）,Z=-0.246,P=0.806].Conclusions Serum IL 6 level within one hour after birth can be used as a biomarker to predict whitez matter injury in VLBWI and ELBWI.