Kim So-Young, Jeong Tae Dong, Lee Woochang, Chun Sail, Min Won-Ki
Department of Medicine, Graduate School, Kyung Hee University, Seoul, South Korea.
Department of Laboratory Medicine, University of Ulsan College of Medicine and Asan Medical Center, Seoul, South Korea.
Ann Clin Biochem. 2015 Nov;52(Pt 6):654-9. doi: 10.1177/0004563214568685. Epub 2015 Jan 9.
The aim of this study was to evaluate the use of procalcitonin in the assessment of bacteraemia in patients in the emergency department, both alone and in conjunction with existing inflammatory markers of bacterial infection.
We enrolled 3305 cases (range 20-90 years) for which we retrospectively compared procalcitonin concentration, blood culture results, body temperature, absolute neutrophil count, and C-reactive protein concentration. The positive predictive value and the negative predictive value of procalcitonin were established at different cut-off concentrations. Receiver operating characteristic curves were plotted, and the areas under the ROC curves calculated, to allow assessment of the diagnostic accuracy of (a) a combination of three existing inflammatory markers of bacterial infection (body temperature, C-reactive protein, absolute neutrophil count), and (b) this combination with procalcitonin.
Positive predictive values of procalcitonin using 0.1, 1, 2, and 5 ng/mL as the cut-off values were 21.2, 32.2, 34.2, and 37.0%, respectively. Negative predictive values of procalcitonin using 0.1, 1, 2, and 5 ng/mL as the cut-off values were 95.1, 92.2, 91.1, and 89.0%, respectively. Areas under the curve of three inflammatory markers (absolute neutrophil count, C-reactive protein, and body temperature) combined was 0.879; areas under the curve of these markers combined with procalcitonin was 0.932 (p = 0.018).
When procalcitonin is used as a serum marker for ruling out bacteraemia, a cut-off of 0.1 ng/mL may be used. Procalcitonin improves the diagnostic accuracy of existing markers of bacteraemia.
本研究的目的是评估降钙素原在急诊科患者菌血症评估中的应用，包括单独使用以及与现有的细菌感染炎症标志物联合使用的情况。
我们纳入了3305例患者（年龄范围20 - 90岁），对其降钙素原浓度、血培养结果、体温、绝对中性粒细胞计数和C反应蛋白浓度进行回顾性比较。在不同的截断浓度下确定降钙素原的阳性预测值和阴性预测值。绘制受试者工作特征曲线，并计算曲线下面积，以评估（a）三种现有的细菌感染炎症标志物（体温、C反应蛋白、绝对中性粒细胞计数）组合，以及（b）该组合与降钙素原联合使用时的诊断准确性。
以0.1、1、2和5 ng/mL作为截断值时，降钙素原的阳性预测值分别为21.2%、32.2%、34.2%和37.0%。以0.1、1、2和5 ng/mL作为截断值时，降钙素原的阴性预测值分别为95.1%、92.2%、91.1%和89.0%。三种炎症标志物（绝对中性粒细胞计数、C反应蛋白和体温）组合的曲线下面积为0.879；这些标志物与降钙素原联合使用的曲线下面积为0.932（p = 0.018）。
当使用降钙素原作为排除菌血症的血清标志物时，可采用0.1 ng/mL的截断值。降钙素原提高了现有菌血症标志物的诊断准确性。
