感染性心内膜炎患者外周血中性粒细胞外诱捕网水平与T 细胞水平表达和预后的相关性研究

目的 探讨感染性心内膜炎(infective endocarditis，IE) 患者外周血中性粒细胞外诱捕网(neutrophil extracellulartrap nets，NETs) 水平与T 细胞水平表达和预后的相关性。方法 选取2018 年11 月～ 2021 年2 月在青岛阜外心血管病医院治疗的53 例IE 患者作为IE 组，选取同期进行体检的50 例健康人群，作为对照组。比较两组血浆NETs 水平和T 细胞表达水平之间的差异，采用Pearson 相关性检验分析血浆NETs 水平和 T 细胞水平表达的相关性。根据IE 患者生存情况分为存活组（29 例）和死亡组（24 例），采用受试者工作特征曲线（ROC 曲线）分析血浆NETs 水平对IE患者死亡的预测价值。结果 IE 组患者cf-DNA/NETs（465.15±146.38μg/L），WBC（16.14±5.36）×109/L，NEUT（75.42±10.25）%，hs-CRP（39.38±10.75g/L），CD3+（66.23±6.74）%，CD4+（44.35±4.26）%和CD4+/CD8+（1.65±0.43）水平均显著高于对照组135.76±37.52 μg/L，（6.24±1.53）×109/L，（62.28±6.45）%，2.37±1.04g/L，（54.21±5.13）%，（35.14±3.52）%，1.34±0.33]，差异有统计学意义（t=18.093，11.036，7.352，22.960，9.505，10.298，5.289，均P ＜ 0.01）。血清Alb（35.38±10.75g/L vs 42.15±9.78 g/L）和CD8+ 水平(23.75±3.68)% vs(26.75±3.66)%] 显著低于对照组，差异有统计学意义（t=-4.039，-4.961，均P ＜ 0.01)。IE 死亡组cf-DNA/NETs 水平显著高于存活组(611.46±102.15μg/L vs407.53±76.49μg/L)，差异均有统计学意义（t=7.007，P ＜ 0.01）。血浆cf-DNA/NETs 水平与CD8+ 水平、患者预后不良呈正相关（r=0.282，0.352，均P ＜ 0.05)，与CD3+，CD4+ 和CD4+/CD8+ 水平呈负相关(r=-0.424，-0.535, -0.328，均P ＜ 0.05）。ROC 曲线分析NETs 预测IE 患者死亡的曲线下面积为0.736（95%CI:0.684 ～ 0.829，P ＜ 0.01）。结论 感染性心内膜炎患者血浆NETs 水平显著升高，血浆NETs 水平与T 细胞水平表达及患者预后不良显著相关，对预测IE 患者死亡有一定临床价值。

Correlation between the Level of Peripheral Blood Neutrophil Extracellular Trap Nets and T Cell Expression and Prognosis in Patients with Infective Endocarditis

Objective To investigate the correlation between the level of peripheral blood neutrophil extracellular trap nets (NETs) and T cell expression and prognosis in patients with infective endocarditis (IE). Methods 53 patients with IE treated in Qingdao Fuwai Cardiovascular Hospital from November 2018 to February 2021 were selected as IE group, and 50 healthy people who underwent physical examination in the hospital during the same period were selected as control group. Plasma NETs levels and T cell expression levels were measured and compared between the two groups. Pearson correlation test was used to analyze the correlation between plasma NETs level and T cell level expression. According to the survival of IE patients, the patients were divided into the survival group (29 cases)and the death group (24 cases). Receiver operating characteristic curve (ROC curve) was used to analyze the predictive value of plasma NETs levels for death in IE patients. Results The levels of cf-DNA/NETs （465.15±146.38μg/L），WBC（16.14±5.36）×109/L, NEUT（75.42±10.25）%, hs-CRP（39.38±10.75g/L）, CD3+ （66.23±6.74）%, CD4+（44.35±4.26）% and CD4+/CD8+（1.65±0.43）in IE group were significantly higher than those in control group135.76±37.52 μg/L，（6.24±1.53）×109/L，（62.28±6.45）%，2.37±1.04g/L，（54.21±±5.13）%，（35.14±3.52）%, 1.34±0.33]，the differences were statistically significant（t=18.093，11.036，7.352，22.960，9.505，10.298, 5.289, all P ＜ 0.01）. Serum Alb （35.38±10.75g/L vs 42.15±9.78 g/L）and CD8+(23.75±3.68)% vs (26.75±3.66)%]levels were significantly lower than control group ，the differences were statistically significant （t=-4.039，-4.961，all P ＜ 0.01). The cf-DNA/NETs level in IE death group was significantly higher than that in IE survival group (611.46±102.15μg/L vs 407.53±76.49μg/L) ，the difference was statistically significant (t=7.007, P ＜ 0.01). Plasma cf-DNA/NETs levels were positively correlated with CD8+ and poor prognosis in IE group (r=0.282 ，0.352, all P ＜ 0.05), and negatively correlated with CD3+, CD4+ and CD4+/CD8+ (r=-0.424, -0.535，-0.328, all P ＜ 0.05).The ROC curve analysis showed that the area under the curve for NETs to predict death in IE patients was 0.736 (95%CI: 0.684 ～ 0.829, P ＜ 0.01). Conclusion Plasma NETs was significantly increased in patients with infective endocarditis. plasma NETs level was significantly correlated with T cell level expression and poor prognosis, which has certain clinical value in predicting death in patients with IE.