Cabral Luís, Afreixo Vera, Santos Filipe, Almeida Luís, Paiva José Artur
Department of Plastic Surgery and Burns Unit, Coimbra Hospital and University Centre (CHUC), Coimbra, Portugal; Department of Medical Sciences, University of Aveiro, Aveiro, Portugal.
CIDMA - Center for Research and Development in Mathematics and Applications, iBiMED - Institute for Biomedicine, University of Aveiro, Aveiro, Portugal.
Burns. 2017 Nov;43(7):1427-1434. doi: 10.1016/j.burns.2017.03.026. Epub 2017 Apr 25.
The gold standard for sepsis diagnosis in burn patient still relies on microbiological cultures, which take 48-72h to provide results, delaying the start of antimicrobial therapy. Thus, biomarkers allowing an earlier sepsis diagnosis in burn patients are needed.
This retrospective observational study included 150 burn patients with total burned surface area ≥15%. Clinical diagnosis of sepsis among these patients was done according to the American Burn Association criteria. Biomarker (procalcitonin, white blood cells and platelet countings, prothrombinemia, D-dimers, C-reactive protein, blood lactate and temperature) values were available for 48 patients without sepsis (2767 timepoints) and 102 patients with sepsis (652 timepoints). Quantitative variables were compared with Mann-Whitney tests and qualitative variables were compared with Pearson chi-square test. Effect size was measured by the probability of superiority. Receiver operating characteristic (ROC) curves evaluate capacity for sepsis diagnosis. Sensitivity, specificity, positive and negative predictive values were calculated for some cut-off values, including the best cut-off defined by the maximum of Youden index.
Statistically significant differences between the groups of septic and non-septic patients, with medium to large effect size, were detected for all the biomarkers considered, except temperature. PCT was the biomarker with the largest AUC and effect size (AUC=0.71). Analysis of the PCT ROC curve showed that 0.5ng/mL cut-off presented highest sensitivity and lowest specificity, whereas 1.5ng/mL cut-off was associated with lowest sensitivity and highest specificity.
Procalcitonin showed to be the best of the biomarkers studied for an early diagnosis of sepsis. Its use should be considered in antimicrobial stewardship programs in Burn Units.
烧伤患者脓毒症诊断的金标准仍然依赖于微生物培养，而微生物培养需要48 - 72小时才能得出结果，从而延迟了抗菌治疗的开始。因此，需要能够在烧伤患者中更早诊断脓毒症的生物标志物。
这项回顾性观察研究纳入了150例烧伤总面积≥15%的患者。这些患者的脓毒症临床诊断依据美国烧伤协会标准进行。48例无脓毒症患者（2767个时间点）和102例有脓毒症患者（652个时间点）的生物标志物（降钙素原、白细胞和血小板计数、凝血酶原血症、D - 二聚体、C反应蛋白、血乳酸和体温）值可用。定量变量采用曼 - 惠特尼检验进行比较，定性变量采用皮尔逊卡方检验进行比较。效应大小通过优势概率来衡量。采用受试者工作特征（ROC）曲线评估脓毒症诊断能力。针对一些截断值计算了敏感性、特异性、阳性和阴性预测值，包括由约登指数最大值定义的最佳截断值。
除体温外，在所有考虑的生物标志物中，脓毒症患者组和非脓毒症患者组之间均检测到具有中等到大效应大小的统计学显著差异。降钙素原是AUC和效应大小最大的生物标志物（AUC = 0.71）。降钙素原ROC曲线分析表明，0.5ng/mL的截断值具有最高敏感性和最低特异性，而1.5ng/mL的截断值则与最低敏感性和最高特异性相关。
降钙素原是所研究的用于脓毒症早期诊断的最佳生物标志物。在烧伤病房的抗菌管理计划中应考虑使用它。
