Xinghua Ye Jia Wang Le Hu Ying Zhang Yixuan Li Jingchao Xuan Silu Han Yifan Qu Long Yang Jun Yang Junyu Wang Bing Wei ^*

• Emergency Medicine Clinical Research Center, Beijing Chao-Yang Hospital Jingxi Branch, Capital Medical University, & Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing, China

Objective: To determine the diagnostic and prognostic value of soluble suppression of tumorigenicity 2 (sST2) in patients with sepsis.Methods: A total of 113 critically ill patients were enrolled at the emergency department of Beijing Chaoyang Hospital Jing Xi Branch. Venous blood levels of sST2 were measured using the AFIAS-6 dry fluorescence immunoassay analyzer. Based on Sepsis 3.0 criteria, patients were categorized into a sepsis group (76 cases) and a non-sepsis group (37 cases). The sepsis group was further divided into non-survivors (38 cases) and survivors (38 cases) based on 28-day survival outcomes.The vital signs, blood gas analysis, routine blood tests, liver and kidney function tests, procalcitonin (PCT), C-reactive protein (CRP), sST2, left ventricular ejection fraction (LVEF), and other basic characteristics of the patients were recorded. Further, the SOFA, qSOFA and APACHE Ⅱ scores of each patient were calculated. Statistical analysis was performed using SPSS 25.0, including logistic regression and ROC curve analysis to assess prognostic factors.The serum sST2 levels in the sepsis group (125.00±60.32ng/ml) were significantly higher than in the non-sepsis group (58.55±39.03ng/ml) (P<0.05). The SOFA score (8.08±2.88), APACHE Ⅱ score (18.00±4.72), blood sST2 levels (168.06±36.75ng/ml) and lactic acid levels (2.89±3.28) in the non-survivor group were significantly higher than the survivor group (p<0.05).Multiple logistic regression analysis showed that sST2, SOFA score, APACHE Ⅱ score and lactic acid levels were independent risk factors for poor prognosis in patients with sepsis. The ROC curve analysis of the above indexes showed no significant differences between the AUC of sST2 (0.912) and the SOFA score (0.929) (z = 0.389, p = 0.697), or the APACHE Ⅱ score (0.933) (z = 0.484, p = 0.627). However, there was a significant difference between the AUC of sST2 (0.912) and lactic acid levels (0.768) (z = 2.153, p = 0.030).Blood levels of sST2 show a clinically diagnostic and prognostic value in sepsis.Further, sST2 shows a similar predictive ability as the SOFA and APACHE Ⅱ scores in determining the prognosis of sepsis patients. However, sST2 has a higher predictive ability than lactic acid levels in determining prognosis in sepsis.