Abstract: Objective: To investigate the correlation of serum interleukin 33（IL-33）and its receptor soluble suppression of tumorigenicity 2(sST2） with injury severity score(ISS) and prognosis in trauma patients. Methods: According to ISS, 67 trauma patients were divided into 2 groups, mild trauma group (ISS<20 points）and severe trauma group（ISS≥20 points）.Serum levels of IL-33, sST2 were measured at 4 h, 24 h, 72 h, 7 d after trauma, and mortality in 28 days were compared between mild trauma group and severe trauma group .Serum levels of IL- 33 and sST2 were compared between the survival and the dead patients. The receiver operating characteristic（ROC） curve was used to determine the cutoff value of indices for predicting the death of patient. Results: The levels of serum IL-33 and sST2 were significantly higher in severe trauma patients than those with mild trauma at 4 h and 24 h [IL-33, （38.75±28.43） pg/mL vs （19.62±9.98） pg/mL, （42.31±37.37） pg/mL vs （23.47±13.42） pg/mL, P<0.05; sST2,（6.50±3.74） ng/mL vs （4.89±2.40） ng/mL, （8.35±2.69） ng/mL vs （6.78±3.22） ng/mL, P<0.05]. The levels of serum IL-33 and sST2 were significantly higher in dead patients than in survival patients during 24 h-7d after trauma (P<0.01). The area under ROC curve of serum IL-33 and sST2 levels at 24 h after trauma were 0.799 (P=0.003) and 0.751( P=0.012), respectively. The optimal cutoff value of serum IL-33 and sST2 levels at 24 h after trauma were 15.27 pg/mL and 10.99 ng/mL respectively, and the sensitivity and specificity for predicting death were 100% and 70%,and 64% and 83%, respectively. Conclusions: Elevated levels of IL-33 and sST2 are associated with poor prognosis in patients with trauma, and serum IL-33 and sST2 at 24 h after trauma could be used as biomarkers for predicting prognosis in patients with trauma.

Key words: Trauma, Interleukin 33, Soluble suppression of tumorigenicity, Injury severity score, Prognosis