血清降钙素原水平与细菌感染的相关性分析

Study on the relationship between serum levels of procalcitonin and bacteral infectious disease

目的探讨血清降钙素原(PCT)检测在感染性疾病中的临床意义,分析血清PCT水平与细菌感染的相关性。方法研究对象为356例各种感染性疾病患者,其中细菌感染98例,病毒感染258例,采用半定量固相免疫测定法测定患者血清中的PCT,结果分为<0.5ng/ml;≥0.5ng/ml;≥2.0ng/ml和≥10ng/ml四个等级。组间差异采用卡方检验。结果若以血清PCT≥0.5ng/ml以上为阳性标准,并结合全身炎性反应综合征(SIRS)参数,血清PCT检测对细菌感染诊断的敏感性为98.7％,特异性为72.0％,阳性预测值为49.4％,阴性预测值为99.5％,阳性拟然比为3.53,阴性拟然比为0.018,诊断符合率为77.80％。血清PCT阳性患者SIRS、MODS和MOF的发生率明显高于血清PCT阴性患者(P<0.01),5例死亡患者血清PCT均阳性,其中3例≥2ng/ml,2例PCT≥10ng/ml。结论血清PCT半定量检测可用于细菌感染与病毒感染的鉴别诊断,结合SIRS参数可提高对细菌感染诊断的敏感性和特异性,为抗生素的使用提供可靠依据;同时,PCT水平的高低反映了病情的严重程度,可作为评估病情,判断预后的指标;PCT在由SIRS向多器官功能障碍综合征或多器官功能衰竭的发生发展过程中可能发挥着重要作用。

Objective To investigate clinical significance of detecting serum procalcitonin (PCT) in various infectious diseases, and the relationship be- tween serum levels of procalcitonin and bacterial in- fectious disease. Methods Serum PCT were mea- sured by semi-quantitative solid-phase immunoassay, and PCT levels were categorized into four groups: <0. 5ng/ml, ≥0.5ng/ml, ≥2ng/ml and ≥10ng/ ml. It was analysed that the relationship between serum levels of procalctionin and viral infection or bacterial infection. Results If PCT levels (≥0. 5ng/ ml) was taken as diagnostic standard and adding in systemic inflammatory response syndrome (SIRS) parameter, the test's sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio and accuracy ratio in diagnosing bacterial infectious diseases were 98.7%, 72. 0%, 49. 4%, 99. 5%, 3. 53, 0. 018 and 77. 8%, respectively. Conclusion The study suggests that semi-quantitative detection of serum PCT might help us to identify bacterial infection or non-bacterial infection, and might offer valuable data for antibiotic therapy. On the other hand, serum PCT levels may reflect infectious disease severity. Fi- nally, PCT may have important role in pathogenesis from SIRS to multiple organ failure.