线粒体偶联因子6、细胞色素C在新生儿败血症中的变化及临床意义

目的 检测新生儿败血症时血浆线粒体偶联因子6(coupling factor 6,CF6)、细胞色素C水平的变化,探讨其在新生儿败血症中的临床意义.方法 以2015年1月至2015年4月湖南省儿童医院新生儿科收治的日龄3~28d内的足月新生儿88例为研究对象,根据感染情况将患儿分为非败血症组(42例)和败血症组(46例);根据感染严重程度,进一步将非败血症组分为无感染组(20例)、感染致炎症反应组(22例),败血症组分为普通败血症组(31例,无器官功能衰竭)和重症败血症组(15例,有多器官功能衰竭).所有患儿均在入院后未用抗生素前采集股静脉血,用ELISA法检测入院后血浆CF6、细胞色素C的活性水平,同时检测C-反应蛋白(C-reactive protein,CRP)、降钙素原(procalcitonin,PCT),比较血浆CF6、细胞色素C的变化情况;与传统临床诊断新生儿败血症的非特异性指标(CRP、PCT)进行比较,探讨其敏感度及特异度;对CF6、细胞色素C的活性水平与新生儿危重症评分进行相关性分析.结果 (1)入院时败血症组CF6、细胞色素C水平分别为(109.7±8.9)pg/ml和(44.5±4.9)ng/ml,显著高于非败血症组(46.3±6.0)pg/ml、(31.8±6.7)ng/ml,P均<0.01];(2)无感染组、感染致炎症反应组、普通败血症组、重症败血症组CF6水平分别为(32.1±8.9)pg/ml、(59.3±7.2)pg/ml、(79.3±5.9)pg/ml、(172.6±6.1)pg/ml;细胞色素C水平分别为(29.3±8.6)ng/ml、(35.4±4.1)ng/ml、(43.1±5.9)ng/ml、(44.5±5.9)ng/ml;各组间比较差异有统计学意义(P<0.01);(3)受试者工作特征曲线分析显示,CF6、细胞色素C的敏感度和特异度分别为0.761、0.732,0.739、0.714;(4)血浆CF6、细胞色素C与新生儿危重症评分呈负相关(r=-0.599,P<0.001;r=-0.337,P<0.01).CF6、细胞色素C随着病情严重程度的加重而升高.结论 新生儿败血症时血浆CF6、细胞色素C水平有升高趋势,其可能与线粒体受损有关.血浆CF6、细胞色素C水平与新生儿败血症病情严重程度具有相关性,对临床有一定指导意义.

Changes and clinical significances of mitochondrial coupling factor 6 and cytochrome C in neonatal sepsis

Objective To evaluate the levels of plasma coupling factor 6(CF6) and cytochrome C(Cyt-c) in neonatal sepsis,and to explore the clinical significance in neonatal sepsis.Methods A total of 88 neonates admitted to Hunan Children's Hospital from January 2015 to April 2015 were collected.Neonates were divided into non-sepsis group(n=42) and sepsis group(n=46).According to the severity of infection,the non-sepsis group was further divided into non-infection group(n=20) and common infection group(n=22);the sepsis group was further divided into general sepsis group (31 cases,no organ failure) and severe sepsis group (15 cases,combined with multiple organ failure).Femoral venous blood was collected in all patients before the use of antibiotics after admission.The levels of Cyt-c and CF6 in plasma were measured by ELISA,and the levels of C-reactive protein(CRP),procalcitonin (PCT) were measured.The changes of CF6 and Cyt-c between these groups were compared,and the sensitivity and specificity with the traditional sepsis index (CRP,PCT) were analyzed.The correlation between the levels of CF6,Cyt-c and neonatal critical illness score was analyzed.Results (1)In sepsis group,the levels of CF6 and Cyt-c(109.7±8.9)pg/ml and (44.5±4.9)ng/ml] were significantly higher than those in the non-sepsis group(46.3±6.0)pg/ml,(31.8±6.7)ng/ml,P<0.01,respectively].(2) In the non-infection group,common infection group,general sepsis group and severe sepsis group,the levels of CF6 were (32.1±8.9)pg/ml,(59.3±7.2)pg/ml,(79.3±5.9)pg/ml,and (172.6±6.1)pg/ml,respectively;the levels of Cyt-c were (29.3±8.6)ng/ml,(35.4±4.1) ng/ml,(43.1±5.9) ng/ml,and (44.5±5.9)ng/ml,respectively.The differences between these groups were significant(P<0.01).(3)The receiver operating characteristic curve showed that the sensitivity and specificity of CF6 were 0.761,0.732,and the Cyt-c were 0.739,0.714.(4)Cyt-C and CF6 were negatively correlated with the neonatal critical illness score(r=-0.599,P<0.001;r=-0.337,P<0.01).Conclusion The levels of CF6 and Cyt-c increase in neonatal sepsis.The damage of mitochondria may be one of the pathological mechanisms in neonatal sepsis.The levels of CF6 and Cyt-c were closely related to the severity of neonatal sepsis.