降钙素原和超敏C反应蛋白预测败血症血液培养阳性的临床价值

Clinical value of procalcitonin and hs-CRP in predicting positive blood culture results in sepsis

目的探讨和比较降钙素原(PCT)和超敏C反应蛋白(hs-CRP)预测败血症患者血液培养阳性的临床价值。方法132例败血症患者纳入该研究,在应用抗菌药物治疗前进行血液培养实验,并检测白细胞计数、中性粒细胞绝对值、PCT、hs-CRP,评价PCT和hs-CRP预测血液培养阳性的应用价值。结果血液培养阳性与血液培养阴性者PCT的中位浓度分别为7.92ng/mL和0.95ng/mL,差异有统计学意义(P<0.01)。PCT预测血液培养阳性的准确率明显高于hs-CRP,曲线下面积(AUC)分别为0.810(P=0.001)和0.690(P=0.247)。PCT与hs-CRP联合应用预测血液培养阳性与单独应用PCT预测血液培养阳性的检测结果相似,AUC为0.885(P=0.001)。PCT的中位截点为0.91ng/mL时,预测血液培养阳性的灵敏度为90%;PCT的截点为1.14ng/mL时,这一灵敏度仍保持不变。这两个截点水平可以减少51%和56%的不必要的血液培养送检申请。结论与hsCRP相比较,PCT水平可更好地预测败血症患者血液培养阳性率。

Objective To investigate and compare the clinical values of serum procalcitonin（PCT）and high sensitivity C-reactive protein（hs-CRP）levels for predicting the blood culture positivity in the patients with sepsis.Methods 132 adult patients with sepsis were enrolled in this study.Blood cultures were performed before the antibacterial therapy.The white blood cell（WBC）count,absolute neutrophil count（ANC）,levels of PCT and hs-CRP were determined.The application value of PCT and hs-CRP for predicting the positive blood culture results were evaluated.Results The median serum PCT levels in the blood culture positive group and the blood culture negative group were 7.92ng/mL and 0.95ng/mL respectively,the difference had statistical significance（P〈0.01）.The receiver operating characteristic（ROC）curves showed that PCT had a higher predictive accuracy for blood culture positivity compared with hs-CRP,the area under the curve（AUC）was 0.810（P=0.001）and 0.690（P=0.274）,respectively.The combined detection of PCT and hs-CRP for predicting the blood culture positive results was similar to the performance of PCT alone,AUC as 0.885（P=0.001）.The median cut point of PCT was 0.91ng/mL,the sensitivity of PCT for predicting blood culture positivity was 90%.This sensitivity remained unchanged when PCT cut point was1.14ng/mL.Using the PCT cut points of 0.91 and 1.14 enabled reducing the submitted blood cultures by 51% and 56% respectively.Conclusion Compared with hs-CRP,serum PCT level could better predict the blood culture positivity in the patients with sepsis.