血清降钙素原鉴别细菌性感染的临床价值

目的比较血清降钙素原(PCT)水平与其他炎症指标对鉴别诊断细菌性感染的临床价值。方法采用回顾性队列研究,按临床病例终诊结果将患者分为细菌性感染和非细菌性感染两组,采用受试者工作特征曲线比较PCT、C反应蛋白(CRP)、白细胞计数(WBC)3项炎症指标对细菌性感染的诊断价值。结果预测细菌性感染的ROC曲线下面积PCT为0.89,CRP为0.70,WBC为0.60;以PCT>0.25 ng/mL为阳性界值诊断细菌性感染的灵敏度为46%,特异度为100%;以PCT≥0.1 ng/mL为临界值则灵敏度达75%,特异度96%;CRP>5 mg/L的诊断灵敏度为85%,特异度为38%;WBC>10.0×109/L的诊断灵敏度为39%,特异度为82%。结论在鉴别细菌性感染和其他炎症疾病上,血清PCT优于CRP和WBC,以PCT≥0.1 ng/mL为阳性界值,对诊断有最佳的灵敏度和特异度。

The clinical significance of serum procalcitonin in discriminating bacterial infection

Objective To compare the clinical value of serum procalcitonin （PCT）and other inflammatory markers in differential diagnosis of bacterial infection from other inflammatory processes. Methods Retrospective cohort study was adopted, and the patients were divided into two groups according to the final clinical diagnosis：group I with bacterial infection and group Ⅱ with abacterial inflammatory disease. Then we compared the levels of serum PCT,C reactive protein（CRP） and white blood cell count（WBC） by ROC curve,and studied the diagnostic value of these three inflammatory markers. Results Area under the ROC curve for the prediction of bacterial infection was 0.89 for PCT,0.70 for CRP and 0.60 for WBC. The diagnostic sensitivity and specificity of bacterial infection were 46% and 100% respectively when PCT was 〉0.25 ng/mL,75%and 96% when PCT was ≥0.1 ng/mL,and diagnostic sensitivity and specificity of bacterial infection were 85% and 38% when CRP was 〉5 mg/L, the sensitivity and specificity of bacterial infection were 39% and 82% when WBC was 〉 10. 0 × 10^9/L. Conclusion The serum PCT is a much better marker than CRP and WBC in differential diagnosis of bacterial infection from other inflamma tory diseases,and the PCT cutoff level that combined the greatest sensitivity and comparatively good sepeificity is ≥0.1 ng/mL.