[Clinical features and significance of coagulation dysfunction in severe fever with thrombocytopenia syndrome]

To analyze the changes of coagulation function in severe fever with thrombocytopenia syndrome (SFTS) and its relationship with thrombocytopenia, and to explore its value as an early predictor of the severity of SFTS. The clinical data of 428 SFTS patients (70 deaths and 358 survivors) admitted to the Department of Infectious Disease at Wuhan Union Hospital from January 2014 to July 2020 were retrospectively analyzed. The differences of coagulation parameters and disseminated intravascular coagulation (DIC) scores between the two groups were compared. The results showed that abnormal coagulation function was commonly presented in SFTS patients. Bleeding was more frequent in mortality group (41.4% vs. 26.5%). The D-dimer levels in mortality patients were significantly higher above normal range. Activated partial thrombin time (APTT) and thrombin time (TT) were significantly prolonged. The levels of prothrombin time (PT), TT, APTT, international standardized ratio (INR) and D-dimer between mortality group and survival group started to separate from day 5-6. The difference of fibrinogen (FIB) level developed on day 7-8, while platelet counts between the two groups were significant different from day 9-10. The mortality rate increased according to the increase of baseline DIC score. When DIC score reached 6, the mortality rate surged to 66.67%. Excessive platelet consumption is mediated by significant coagulation abnormalities during disease course, and coagulation parameters are more sensitive than platelet count as an early predictor of severe SFTS.分析发热伴血小板减少综合征（severe fever with thrombocytopenia syndrome，SFTS）患者凝血功能的临床变化特点及其与血小板减少的关系，探索其作为早期预测SFTS患者重症化趋势的价值。分析2014年1月至2020年7月华中科技大学同济医学院附属协和医院感染科收治的428例SFTS患者（其中死亡组70例，存活组358例）的临床资料，统计分析两组患者凝血相关指标以及弥散性血管内凝血（DIC）评分的差异。结果显示，SFTS患者凝血功能异常常见，死亡组较存活组更易出现出血症状（出血发生率41.4%比26.5%）；死亡组D-二聚体水平显著高于正常水平，活化部分凝血酶时间（APTT）、凝血酶时间（TT）均显著延长。死亡组与存活组患者凝血酶原时间（PT）、TT、APTT、国际标准化比值（INR）、D-二聚体在第5~6天开始出现统计学差异；纤维蛋白原（FIB）水平在第7~8天开始出现统计学差异，均早于血小板计数水平在两组患者中出现差异的时间（第9~10天）。SFTS病死率随基线DIC评分升高而升高，当DIC评分达到6时，病死率达到66.67%。疾病过程中显著的凝血异常介导血小板消耗过多，凝血相关指标较血小板计数对早期识别SFTS重症化更有帮助。.