降钙素原与血培养联合检测以改善脓毒症诊断的敏感性及协助鉴别污染菌

目的 比较血培养单检与降钙素原（PCT）加血培养双检对脓毒症诊断的敏感性及协助鉴别污染菌.方法 收集644例急诊或重症监护室临床医师怀疑新发生严重感染患者同天的血培养及PCT样本,对未开PCT检测的病患同时检测PCT,以出院脓毒症确诊为金标比较血培养单检及PCT加血培养双检对脓毒症的诊断及血培养污染诊断的敏感性与特异性.结果 脓毒症病患中血培养单检的敏感性为34.1%,特异性为90.1%,假阳性率为9.9%,假阴性率为65.9%,阳性预测值为57.0%,阴性预测值为78.0%.二者双检的敏感性为98.4%,特异性为90.1%,假阳性率为10.2%,假阴性率为1.6%,阳性预测值为79.2%,阴性预测值为99.3%.结论 血培养单检对脓毒症的诊断存在着污染菌的干扰因素,PCT与血培养联合检测对脓毒症的诊断比血培养单检更具有诊断价值,从而及时有效的指导临床合理应用抗生素治疗,减少耐药株的产生,从而降低死亡率.

The joint detection of PCT and blood culture to improve the sensitivity of sepsis diagnosis and contaminant bacteria differential diagnosis

Objective Comparing the sensitivity of sepsis diagnosis between blood culture and joint detection of blood culture and PCT, helping diagnosis of contaminant bacteria. Methods Collected 644 PCT and blood culture samples from Emer- gency or ICU patients who were doubted new serious infection, each of the patient did blood culture and PCT detection. Compared the sensitivity and specificity of blood culture and the joint detection of the two test for sepsis diagnosis and contaminant bacteria diagnosis of blood culture. Results In sepsis patients, the sensitivity of blood culture and the joint detection is 34. 1% and 98. 4% respectively, specificity is 90. 1% and 90. 1% respectively , false positive rate is 9. 9% and 10. 2% respectively, false negative rate is 65.9% and 1.6% respectively, positive predictive value is 57.0% and 79. 2% respectively, negative predictive value is 78.0% and 99. 3% respectively. Conclusion The contaminant bacteria can interference the sepsis diagnosis in blood culture only. The joint detection of PCT and blood culture is of essential value in diagnosing sepsis than blood culture only, and great improved the positive rate of sepsis diagnosis, and this will guide the rational use of antibiotics in clinical treatment timely and effectively, reduce drug-resistant strain, thus lower the death rate.