Identification of soluble thrombomodulin and tissue plasminogen activator-inhibitor complex as biomarkers for prognosis and early evaluation of septic shock and sepsis-induced disseminated intravascular coagulation

Endothelium injury and coagulation dysfunction play an important role in the pathogenesis of sepsis. Soluble thrombomodulin (sTM), tissue plasminogen activator-inhibitor complex (t-PAIC), thrombin-antithrombin complex (TAT) and α2-plasmin inhibitor-plasmin complex (PIC) are biomarkers of endothelium injury and coagulation dysfunction. This study aimed to explore the prognostic values and diagnostic performance for septic shock and sepsis-induced disseminated intravascular coagulation (DIC) of endothelial biomarkers.We conducted an observational study on patients with sepsis admitted to intensive care unit (ICU) at a teaching hospital from January 2016 to December 2018. Levels of sTM, t-PAIC, TAT and PIC were measured at admission day and day 5-7 after admission and detected by qualitative chemiluminescence enzyme immunoassay performed on HISCL automated analyzers.A total of 179 septic patients and 125 non-septic ICU controls were enrolled. The level of sTM was higher in septic patients compared to ICU controls (OR =1.093, 95% CI: 1.045-1.151, P<0.001). Moreover, higher levels of sTM and t-PAIC were independent predictors of poor 60-day prognosis for septic patients (HR =1.012, 95% CI: 1.003-1.022, P=0.012; HR =1.014, P=0.009). Level of sTM was also higher in patients with septic shock as revealed by multivariate analysis (OR =1.049, 95% CI: 1.020-1.078, P=0.001), as well as in patients with sepsis-induced DIC (OR =1.109, 95% CI: 1.065-1.158, P<0.001). sTM was considered as a sensitive biomarker for the early prediction of septic shock and sepsis-induced DIC, with AUC up to 0.765 (0.687-0.842) and 0.864 (0.794-0.935) of receiver operating characteristic curve.Most patients developed coagulopathy which was closely linked to endothelial injury in initial phase of sepsis, which was demonstrated by abnormalities in endothelial biomarkers and their strong association with poor 60-day prognosis and development of septic shock and sepsis-induced DIC.