The Application Value Of Interleukin-33 And Procalcitonin In Sepsis Diagnosis And Risk Stratification

1 ObjectiveThrough the comparation of interleukin-33(IL-33),procalcitinin(PCT)and SOFA score between septic patients and non-septic patients,analyze the correlations between IL-33,PCT and SOFA score and investigate the application value of interleukin-33 in sepsis diagnosis and risk stratification.2 Methods 2.1 patient enrollmentThis study enrolled 48 patients with severe infection who admitted to the Second Hospital of Shanxi Medical University from January 2016 to December 2016.Patients were divided into two groups: non-sepsis group with 21 patients and sepsis group with 27 patients.27 septic patients were divided into non-septic shock group with 18 patients and septic shock group with 9 patients depending on whether the patients had septic shock.Sepsis diagnostic criterion: according to the the third version of definition of sepsis,calculate the SOFA score of infectious patients according to the past history or the previous data of patients.The definition of sepsis is the SOFA score increased≥2 in the short term after the onset of the disease.Septic shock diagnostic criterion: according to the the third version of definition of sepsis,septic patients still need vasopressors to maintain the mean arterial pressure≥65mmHg after adequate fluid resuscitation and the lactic acid level≥2mmol/L is definited septic shock.Exclusion criteria:(1)age<18 years;(2)pregnant women;(3)patients with autoimmune diseases;(4)patients with severe immunosuppresive state;(5)patients with hematological diseases;(6)patients or their relatives didn’t agree to participate in the study.2.2 Specimen collection and detectionThe patients enrolled into the study got the blood collection of 3ml within 24 hours after admitted in hospital and centrifuged the blood at 3000 rpm / min with 80-1 high speed centrifugal machine produced in Jintan City Cultural Instrument Company for about 3 minutes.The upper plasma was separated and stored in the EDTA tubes and then marked the patient’s names and specimen numbers.The tubes were stored in the German SIEMENS BCD-254(KK25V61TI)refrigerator with a temperature of minus 70 degrees centigrade.Using the ELISA kit purchased by Shanghai Biotech Company to test the samples’ IL-33 and PCT concentration and strictly followed the instructions.2.3 Data AnalysisThe level of IL-33,PCT level and SOFA score between non-sepsis group and sepsis group were compared by single sample t test using SPSS 17.0 software;in patients with sepsis group,comparation with non-septic shock group and septic shock group between IL-33 level and PCT level were conducted using independent sample t test;correlation analysis between IL-33,PCT levels and SOFA scores were conducted using Pearson correlation analysis and the scatter diagram was conducted using SigmaPlot 12.3 software.3 Results 3.1 The PCT level in sepsis group is 7.13±3.47μg/L and in non-sepsis group is 0.51±0.24μg/L;The IL-33 level in sepsis group is 3.88±0.74ng/L and in non-sepsis group is 5.02±1.27ng/L.The SOFA score in sepsis group is 7.04±2.16 and in non-sepsis group is 1.90±0.83;The level of PCT and SOFA score in sepsis group were significantly higher than those in non-sepsis group(P < 0.05).The level of IL-33 in sepsis group was significantly lower than that in non-sepsis group patients(P < 0.05).3.2 In sepsis group,the PCT level in septic shock group is 10.63±2.81μg/L and in non-septic shock group is 5.76±2.05μg/L;The IL-33 level in septic shock group is 3.44±0.56ng/L and in non-septic shock group is 3.99±0.66ng/L.The SOFA score in septic shock group is 9.78 ± 1.89 and in non-septic shock group is 5.89±1.23.The PCT level and SOFA score in septic shock group were significantly higher than those in non-shock group(P < 0.05).The level of IL-33 in septic shock group was lower than that in non-shock group(P < 0.05).3.3 The PCT level was positively correlated with SOFA score in patients with sepsis,and the correlation between IL-33 and PCT,IL-33 and SOFA score were negative.3.4 The area under the curve(AUC)of the IL-33 group was 0.79,P=0.00 and the AUC of PCT was 0.98,P=0.00.The max Youden index of IL-33 was 0.56,and the best cutoff value was 4.45ng/L;The max Youden index of PCT was 0.96,and the best cutoff value was 1.25μg/L.IL-33 and PCT had high diagnostic accuracy.IL-33 can be used as a diagnostic indicator of sepsis to determine the severity of the disease and for risk stratification.4 ConclusionsIL-33 can be used as one of the indicators,examination of IL-33 and PCT can be used to evaluate the severity of sepsis and for risk stratification.