降钙素原联合中性粒细胞/淋巴细胞比值在不同类型血流感染中的应用价值

目的研究降钙素原(PCT)、中性粒细胞/淋巴细胞比值(NLR)在不同类型血流感染(BSI)中的变化及其临床价值。方法收集2017年8月至2018年8月251例血培养阳性住院患者临床资料,分为血培养污染组和BSI组。BSI组进一步分为革兰阴性细菌(G~-)组、金黄色葡萄球菌(SA)组、凝固酶阴性葡萄球菌(CNS)组。分析血常规和PCT数据,分别采用F检验和K-W秩和检验比较不同组的NLR和PCT。绘制受试者工作特征(ROC)曲线评价NLR、PCT及二者联合诊断的临床价值。结果 (1)与血培养污染组比较,BSI组NLR、PCT水平明显增加,差异有统计学意义(P0.01);NLR在G~-组与血培养污染组、血培养SA组与血培养污染组、CNS组与血培养污染组、G~-组与CNS组、SA组与CNS组间比较差异有统计学意义(P0.05),PCT在G~-组与血培养污染组、SA组与血培养污染组、CNS组与血培养污染组比较差异有统计学意义(P0.05)。(2)PCT鉴别BSI与血培养污染、G~-与血培养污染、SA与血培养污染、CNS与血培养污染、G~-与血培养污染的AUC分别为0.895、0.951、0.877、0.919、0.680,具有诊断价值(P0.05)。NLR鉴别BSI与血培养污染、G~-与血培养污染、SA与血培养污染、CNS与血培养污染的AUC分别为0.922、0.934、0.929、0.856,具有诊断价值(P0.05)。PCT+NLR联合检测用于鉴别BSI与血培养污染、G~-与血培养污染、SA与血培养污染、CNS与血培养污染、G~-与SA的AUC分别为0.946、0.950、0.947、0.856、0.664,具有诊断价值(P0.05)。结论PCT和NLR炎性指标在判断血培养污染和BSI中有着明显的优势,在区别不同类型BSI中有一定的应用价值,为鉴别BSI提供了新的思路。     

降钙素原、CD64％、中性粒细胞/淋巴细胞比值、C反应蛋白在 监测早期细菌血流感染中的临床意义

目的探讨降钙素原(PCT)、CD64阳性细胞百分比(CD64%)、中性粒细胞/淋巴细胞比值(NLR)、C反应蛋白(CRP)水平对早期血流感染(BSI)的预测价值。方法回顾性分析BSI 125例,其中血培养阳性的BSI患者100例,血培养阴性患者25例,在血培养的同时抽取外周血检测血常规和PCT、CD64%、CRP水平。比较BSI患者血培养阳性及阴性组间上述炎症血清标志物的差异,并分析其对BSI的预测作用。结果BSI患者PCT、CD64%、CRP、NLR及WBC水平均超过正常临界值,除NLR及WBC外,PCT、CD64%、CRP在血培养阳性组及血培养阴性组患者间水平相当,差异无统计学意义(P0.05)。PCT诊断效能最高,曲线下面积(AUC)达到0.92,灵敏度90.00%,特异度100.00%。同时PCT对革兰阳性(G+)菌株及革兰阴性(G-)菌株均有较好的诊断灵敏度。G-菌中PCT水平高于G+菌,差异有统计学意义(P 0.05)。结论PCT、CD64%、CRP、NLR均有助于诊断早期BSI,其中PCT诊断效能最高,适用于早期BSI筛查。     

血清降钙素原、C反应蛋白联合中性粒细胞/淋巴细胞比值检测在血流感染诊断中的价值研究

目的探讨血清降钙素原(PCT)、C反应蛋白(CRP)联合中性粒细胞/淋巴细胞比值(NLR)检测在血流感染(BSI)诊断中的价值。方法我院300例可疑BSI患者,根据血培养结果分为阳性组与阴性组,比较两组血清PCT、CRP及NLR水平,并分析各指标对BSI的诊断价值。结果 300例可疑BSI患者,血培养阳性32例(10. 67%),血培养阴性168例(89. 33%),病原菌以革兰阴性菌为主,占62. 50%。血培养阳性组血清PCT、CRP及NLR均高于血培养阴性组(P 0. 05)。以血培养结果为金标准,血清PCT、CRP及NLR诊断BSI的ROC曲线下面积分别为0. 796、0. 676、0. 725,三项指标联合检测诊断BSI的敏感度、特异度均高于各单项检测(P 0. 05)。结论血清PCT、CRP及NLR均对早期诊断BSI有重要价值,三者联合检测能够提高诊断敏感度、特异度。     

血培养革兰阳性与阴性菌感染血清降钙素原水平比较

目的探讨患者血清降钙素原（PC T ）水平对区分血培养阳性及革兰阳性（G＋）菌和革兰阴性（G-）菌所致感染的临床应用价值。方法通过对患者血标本细菌培养阳性的标本进行革兰染色及同时检测患者血清PC T水平,比较PC T浓度在革兰阴性细菌及阳性细菌之间的差异,并对其进行敏感性和特异性分析。结果血培养阴性患者PCT为（1．02±0．65）ng/mL ,血培养阳性患者PCT为（8．55±3．62）ng/mL ;G -菌感染组血清PCT含量为（10．78±4．83） ng/mL ;G＋菌感染组血清PCT含量为（4．22±3．16） ng/mL ,两者比较差异有统计学意义（P＜0．05）。结论血清PC T水平测定可作为快速排除和诊断血流感染的辅助检测指标,同时有助于迅速区分G＋菌及G-菌所致的血流感染。     

多指标联合检测在血流感染早期诊断中的价值

目的探讨白细胞(WBC)计数、中性粒细胞百分比(NEUT%)、红细胞分布宽度(RDW)、血清降钙素原(PCT)、中性粒细胞/淋巴细胞比值(NLR)单独和联合检测在血流感染(BSI)早期诊断中的应用价值。方法回顾性分析海军军医大学附属长海医院2019年同时行血培养、PCT和血常规检测的住院患者的病历资料。根据血培养结果进行分组,以168例血培养阳性患者为感染组,以168例随机选取的血培养阴性患者为对照组,比较2组各项检测指标的差异。采用二元Logistic回归分析将WBC计数、NEUT%、RDW、PCT、NLR在早期诊断BSI中的作用进行方程拟合,采用受试者工作特征(ROC)曲线评价各项指标单独和联合检测早期诊断BSI的效能。结果感染组WBC计数、NEUT%、RDW、PCT、NLR水平明显高于对照组(P0.05)。二元Logistic回归分析结果显示,PCT预测BSI的比值比(OR)最高(1.246);NEUT%诊断BSI的曲线下面积(AUC)最大(0.785),以86.35%为截断值,其早期诊断BSI的敏感性为68.45%、特异性为73.81%、准确性为71.13%;NEUT%与PCT联合检测,早期诊断BSI的AUC为0.819,以0.461为截断值,2项指标联合检测早期诊断BSI的敏感性为78.57%、特异性为69.64%、准确性为74.11%。结论 NEUT%、PCT、NLR可作为BSI早期诊断的指标,联合检测临床价值更大。     

血清降钙素原在血流感染革兰阳性菌和阴性菌鉴别诊断中的应用价值

目的探讨血清降钙素原(PCT)检测在血流感染(BSI)革兰阳性菌和革兰阴性菌鉴别诊断中的应用价值。方法选取2013年8月至2016年8月该院收治的129例血培养阳性BSI患者和23例血培养阴性者,采用酶联荧光分析法检测所有受试者血清中PCT水平,分析血清PCT检测在BSI革兰阳性菌和革兰阴性菌鉴别诊断中的应用价值。结果 129例血培养阳性BSI患者中,革兰阳性菌感染69例,占53.49%,革兰阴性菌感染60例,占46.51%。革兰阳性菌感染患者血清PCT水平为2.13(0.57~9.12)ng/mL,明显高于血培养阴性者血清PCT水平[0.24(0.09~1.10)ng/mL],差异有统计学意义(P0.05);革兰阴性菌感染患者血清PCT水平为6.02(1.37~20.04)ng/mL,明显高于革兰阳性菌感染患者的血清PCT水平,差异有统计学意义(P0.05)。当血清PCT临界值为4.32ng/mL,受试者工作特征曲线下面积为0.812,95%CI为0.779~0.923时,此时血清PCT鉴别BSI革兰阳性菌和革兰阴性菌的敏感度为82.30%,1-特异度为75.62%。结论血清PCT检测在BSI革兰阳性菌和革兰阴性菌早期鉴别诊断中有一定的应用价值。     

基于Logistic 回归和 ROC 曲线评价外周血 PCT，CRP，NEU% 和 PLT 水平在血流感染中的联合预测价值

目的　探讨降钙素原（procalcitonin,PCT）、C-反应蛋白（C-reactive protein,CRP）、中性粒细胞百分比（neutrophilpercentage,NEU%）和血小板（platelet,PLT）在血流感染（bloodstream infection,BSI）中的联合预测价值。方法　收集103 例 BSI 疑似患者常规指标 PCT,CRP,WBC,NEU% 和淋巴细胞百分比（lymphocyte percentage,LYM%）、中性粒细胞 / 淋巴细胞（neutrophils/lymphocytes,NEU/LYM）和血培养的检测结果及临床诊断资料,比较 BSI 者与非 BSI 者PCT,CRP,WBC,NEU%,LYM% 和 NEU/LYM 水平差异,将差异有统计学意义的指标纳入 Logistic 逐步回归,建立在 BSI 中联合预测模型,确定联合预测组合,通过受试者工作特征曲线（the receiver operating characteristic curve,ROC）比较预测组合中单个指标与联合预测模型在 BSI 中的预测价值。结果　BSI 者与非 BSI 者的 PCT,CRP,NEU%,LYM%,NEU/LYM 及 PLT 比较,差异均有统计学意义（Z=4.006, 3.214, 2.030, 1.956, 1.966, 2.565, 均 P<0.10）,WBC差异无统计学意义（Z=0.227, P>0.10）。PCT,CRP,NEU%,LYM%,NEU/LYM 及 PLT 被纳入 Logistic 回归。经Logistic 回归,PCT,CRP,NEU% 和 PLT 被纳入建模组合;联合预测模型为 Logit P = - 4.890+1.877PCT+1.345 CRP+1.650NEU%+1.610PLT, 且 PCT,CRP,NEU% 和 PLT 的 优 势 比（OR） 分 别 为 6.5, 3.8, 5.2 和 5.0。PCT,CRP,NEU%,PLT 和联合预测模型的 ROC 曲线下面积（area under ROC curve,AUC）分别为 0.732, 0.686, 0.618, 0.649 和 0.859,联合预测模型 AUC 均明显大于单一指标 AUC（P<0.05）。结论　在 BSI 疑似人群中,PCT,CRP,NEU% 和 PLT 的联合预测模型均比各指标单独应用时有更好的预测价值,单独应用 PCT,NEU% 或 PLT 可协助初步识别 BSI,使用联合预测模型进行综合判断可协助确认 BSI。     

白细胞、降钙素原和C反应蛋白在血流感染早期诊断中的应用价值研究

目的探索白细胞(WBC)、C-反应蛋白(CRP)和降钙素原(PCT)在血流感染(BSI)早期诊断中的临床应用价值,为BSI的早期诊断提供依据。方法回顾性分析48例血液培养阳性患者(血培养阳性组)与50例血液培养阴性患者(血培养阴性组)WBC、PCT和CRP测定结果,比较两组及血培养阳性组中革兰阳性菌与革兰阴性菌感染者各指标检测结果;绘制受试者工作特征(ROC)曲线并计算ROC曲线下面积(AUC);采用二分类Logistic回归对3项指标预测血培养阳性的作用大小进行方程拟合。结果血培养阳性组PCT和CRP水平明显高于血培养阴性组,差异有统计学意义(P0.05),而两组WBC计数比较差异无统计学意义(P0.05)。血培养阳性组中革兰阳性菌与革兰阴性菌感染者仅PCT水平比较差异有统计学意义(P0.05)。WBC、PCT和CRP的AUC分别为0.579、0.746和0.624。二分类Logistic回归显示仅PCT对预测诊断具有统计学意义(P=0.013);三者联合预测诊断的阳性率为71.4%。结论三者均可作为BSI的早期诊断指标,而PCT和CRP较WBC有更重要的意义,并且PCT能较好地区分革兰阳性菌与革兰阴性菌感染。     

降钙素原鉴别血液科患者凝固酶阴性葡萄球菌血流感染与污染的临床价值

目的研究降钙素原(PCT)在血液科患者凝固酶阴性葡萄球菌(CNS)血流感染(BSI)和污染血标本的鉴别诊断价值。方法收集2013-2015年苏州大学附属第一医院血液科住院患者中血培养或导管培养CNS阳性并符合入组标准患者156例,分为CNS BSI组(n=66)及血培养污染组(n=90),比较两组患者性别、年龄、诊断、住院时间、中性粒细胞缺乏时间、中性粒细胞及淋巴细胞计数、热峰值、C反应蛋白(CRP)、PCT等有无差异,有差异者用SPSS 21.0绘制受试者工作特征(ROC)曲线,分析其鉴别诊断价值。结果两组患者之间年龄、性别、临床诊断、住院时间、中性粒细胞缺乏时间、中性粒细胞及淋巴细胞计数差异无统计学意义(P0.05),而热峰值(P0.001)、CRP(P=0.002)和PCT(P=0.018)在两组间差别有统计学意义,BSI组测得值高于污染组(P0.05),对PCT结果作ROC曲线提示正确诊断指数最大时PCT=0.374μg/L,其曲线下面积(AUC)为0.830±0.032(95%CI:0.767~0.893,P0.001),灵敏度为54.5%,特异度为94.4%。结论 PCT对于鉴别CNS引起的BSI或污染有一定的辅助诊断价值,其特异度高于目前临床常用实验室指标CRP,可帮助临床医师及时正确诊断BSI,减少不必要抗生素的使用。     

PCT、CRP、NEU%及WBC在血流感染早期诊断中的应用研究

目的 探讨降钙素原(PCT)、C-反应蛋白(CRP)、中性粒细胞百分比(NEU%)及白细胞计数(WBC)在血流感染(BSI)早期诊断中的价值。方法 回顾性分析2020年1月至2022年1月宁乡市人民医院收治的317例疑似细菌性BSI患者的临床资料,根据血培养结果分为血培养阳性组(156例)和血培养阴性组(161例);再将血培养阳性患者分为革兰阳性菌组(40例)、革兰阴性菌组(105例)及真菌组(11例)。观察PCT、CRP、NEU%及WBC的变化,并比较血培养阳性组中革兰阳性菌、革兰阴性菌和真菌的各指标水平差异,采用受试者工作特征(ROC)曲线评价各指标对BSI早期诊断中的价值。结果 血培养阳性组的PCT、CRP、NEU%、WBC水平均明显高于血培养阴性组,差异均有统计学意义(P<0.05)。3组间PCT水平比较,真菌组>革兰阴性菌组>革兰阳性菌组,差异均有统计学意义(P<0.05)。ROC曲线分析结果显示,PCT、CRP、NEU%、WBC单项检测的ROC曲线下面积分别为0.799、0.694、0.715、0.599,均低于4项联合检测的0.895。结论 PCT...     

Performance enhancement of procalcitonin by high-sensitivity C-reactive protein at the optimal cutoff in predicting bacteremia in emergency department adult patients

Pathogenic bacteremia portends a high mortality risk in adult patients admitted to an Emergency Department (ED). This study aims to investigate the effect of adding high-sensitivity C-reactive protein (hs-CRP) to procalcitonin (PCT) and lactate in predicting bacteremia, Gram-negative (GNB) and Gram-positive bacteremia (GPB), using the optimal cutoff derived from the receiver operating characteristics analysis. We evaluated the diagnostic measures, including the positive-test likelihood (LR+), the negative-test likelihood (LR?), and the diagnostic odds ratio (DOR) using a single-center retrospective analysis design. This Standards for Reporting Diagnostic-compliant study comprised 886 consecutive adults who were admitted to the ED in 2010; to this cohort, a 22.2% prevalence of true bacteremia was subsequently confirmed. At the cutoff of 3.9?μg/L, PCT had a DOR of 5.3 (95% confidence interval [CI]: 3.76–7.61) and LR?+?of 2.8 (95% CI: 2.3–3.4) in predicting overall bacteremia. Elevated PCT and lactate (cutoff at 2?mmol/L), increased the DOR and LR?+?to 6.3 (95% CI: 4.27–9.29) and 4.0 (95% CI: 3.1–5.2). The DOR and LR?+?were further improved to 7.1 (95% CI: 4.2–11.95) and 5.6 (95% CI: 3.7–8.6), respectively, when hs-CRP at the cutoff of 1238?nmol/L was added to PCT plus lactate. High-sensitivity CRP at the cutoff of 1,255?nmol/L can enhance the discriminative power raising DOR and LR?+?values for GPB. The elevation of hs-CRP at the optimal cutoff might improve the diagnostic performance to predict unspecified bacteremia and GPB, but not GNB.     

降钙素原与C-反应蛋白在发热患者病因学鉴别诊断中的价值

目的 探讨降钙素原(PCT)与C-反应蛋白(CRP)在发热患者病因学早期诊断中的应用价值.方法 选取本院收治的52例体温大于38℃的患者为研究对象,检测血清中PCT与CRP的含量并根据临床资料和统计学分析评价其与临床病因学之间的关系.结果 所有患者当中,PCT和CRP均无法区别感染性发热和非感染性发热,两者接受者工作特征曲线下面积分别为0.62(95% CI为0.45～0.78,P=0.14)和0.61(95% CI为0.43～0.79,P=0.22).当PCT临界值分别为0.2 μg/L和10.0 μg/L时,其敏感性和特异性分别为59%和67%、3%和100%.此外,PCT和CRP能区分细菌性发热和病毒性发热(P<0.05).结论 仅根据PCT和CRP无法鉴别患者是否为感染性发热,但能区分病毒性性发热与细菌染性感染.     

Serum procalcitonin measurement contribution to the early diagnosis of candidemia in critically ill patients

Background Candidemia is a life-threatening infection in the ICU whose prognosis is highly dependent on the stage at which it is recognized. Procalcitonin (PCT) levels have been shown to accurately distinguish between bacteremia and noninfectious inflammatory states in critically ill patients with clinical signs of sepsis. Little is known about the accuracy of PCT for the diagnosis of candidemia in this setting.Setting A medical intensive care unit in a teaching hospital.Patients and methods Review of the medical records of every non-neutropenic patient with either bacteremia or candidemia and clinical sepsis in whom PCT dosage at the onset of infection was available between May 2004 and December 2005.Results Fifty episodes of either bacteremia (n = 35) or candidemia (n = 15) were included. PCT levels were found to be markedly higher in patients with bacteremia than in those with candidemia. Moreover, a low PCT value was found to be an independent predictor of candidemia in the study population. According to the calculation of the area under the receiver operating characteristic curve, PCT was found to be accurate in distinguishing between candidemia and bacteremia (0.96 [0.03]). A PCT level of higher than 5.5 ng/ml yields a 100% negative predictive value and a 65.2% positive predictive value for candidemia-related sepsis.Conclusion A high PCT value in a critically ill non-neutropenic patient with clinical sepsis is unlikely in the setting of candidemia.     

血清降钙素原水平预示革兰阴性菌血症的价值评估

目的 评估血清降钙素原(PCT)水平预示革兰阴性(GN)菌血症的价值。方法 选取2013年1月～12月同时进行了血液培养和PCT测定的病例,排除污染生长情况,纳入研究的血液培养阳性499例,依据培养鉴定结果将血液培养阳性病例分组:GN菌血症组314例,其中,男性159例,女性155例; 革兰阳性(GP)菌血症组185例,男性107例,女性78例。对研究对象的血清PCT结果进行统计学处理。结果 GN菌血症组PCT水平(中位数=5.16,0.02～450.10 ng/ml)明显高于GP菌血症组(中位数=0.38,0.02～44.70 ng/ml)(P=0.000); 随着PCT水平的升高,GN菌血症所占比例越来越高,当PCT≥45.0 ng/ml,GN菌血症的比例占到100%; 以6.00 ng/ml为判断值,PCT诊断GN菌血症的灵敏度、特异度、阳性预示值和阴性预示值分别为49.4%,85.2%,85.6%和50.0%,ROC曲线下面积(AUC)为0.714,95%可信区间(CI)为0.672～0.753,SE=0.0229,P<0.000 1。结论 PCT是预示GN菌血症早期的和可靠的标记物,可以早期地指导抗生素治疗的药物选择。     

Development of subsequent bloodstream infection in patients with positive Hickman catheter blood cultures and negative peripheral blood cultures

There are limited data on the incidence of subsequent bloodstream infection (BSI) and the effect of systemic antibiotics in patients who had positive catheter-drawn blood cultures (CBC) and negative peripheral blood cultures (PBC). We retrospectively reviewed all paired blood cultures from patients with Hickman catheter in the hematology-oncology ward between January 1997 and December 2008. There were 112 episodes with positive CBC and negative PBC. Nine episodes (8.0%; 95% CI, 3.0-13.1%) led to subsequent BSI within 28 days. Subsequent BSI developed in 6 of 31 episodes (19%) where empiric antibiotics were inappropriate but in 3 of 81 episodes (4%) where empiric antibiotics were appropriate (P = 0.01). Subsequent candidemia (50%, 2 of 4) was more common than subsequent bacteremia (6%, 7 of 108) (P = 0.03). In conclusion, for patients with positive CBC and negative PBC, the overall incidence of subsequent BSI was 8.0%, and inappropriate empiric antibiotics was associated with subsequent BSI.     

Clinical predictors of Pseudomonas aeruginosa or Acinetobacter baumannii bacteremia in patients admitted to the ED

The identification of clinical characteristics that could identify patients at high risk for Pseudomonas aeruginosa or Acinetobacter baumannii bacteremia would aid clinicians in the appropriate management of these life-threatening conditions, especially in patients admitted to the emergency department (ED) with community-onset infections. To determine clinical risk factors for P. aeruginosa or A. baumannii bacteremia in patients with community-onset gram-negative bacteremia (GNB), a post hoc analysis of a nationwide bacteremia surveillance database including patients with microbiologically documented GNB was performed. Ninety-six patients with P. aeruginosa or A. baumannii bacteremia were compared with 1230 patients with Escherichia coli or Klebsiella pneumoniae bacteremia. A solid tumor or hematologic malignancy was more likely to be associated with P. aeruginosa or A. baumannii bacteremia, whereas concurrent neurologic disease was less frequently seen. In regards to the site of infection, pneumonia was more common in P. aeruginosa or A. baumannii bacteremia, whereas a urinary tract infection was less frequently seen. Factors associated with P. aeruginosa or A. baumannii bacteremia in multivariate analysis included pneumonia (odds ratio [OR], 3.60; 95% confidence interval [CI], 1.86-6.99), hematologic malignancy (OR, 2.71; 95% CI, 1.26-5.84), male sex (OR, 2.17; 95% CI, 1.31-3.58), solid tumor (OR, 1.89; 95% CI, 1.15-3.12), and health-care-associated infection (OR, 1.88; 95% CI, 1.48-2.41). Our data suggest that an initial empirical antimicrobial coverage of P. aeruginosa or A. baumannii bacteremia should be seriously considered in patients with pneumonia, a hematologic malignancy, solid tumor, or health-care-associated infection, when GNB is suspected, even in community-onset infections.     

The ability of Procalcitonin,lactate, white blood cell count and neutrophil-lymphocyte count ratio to predict blood stream infection. Analysis of a large database

BackgroundThe global burden of death due to sepsis is considerable. Early diagnosis is essential to improve the outcome of this deadly syndrome. Yet, the diagnosis of sepsis is fraught with difficulties. Patients with blood stream infection (BSI) are at an increased risk of complications and death. The aim of this study was to determine the diagnostic accuracy of four readily available biomarkers to diagnose BSI in patients with suspected sepsis.MethodsIn this retrospective, observational, Electronic Medical Record based study we compared the accuracy of procalcitonin (PCT), serum lactate concentration, total white blood cell (WBC) count and the neutrophil-lymphocyte count ratio (NLCR) to diagnose BSI in adult patients presenting to hospital with suspected sepsis. Based on the blood culture results patients were classified into 1 of the following 5 groups: i) negative blood cultures, ii) positive for a bacterial pathogen, iii) positive for a potential pathogen, iv) fungal pathogen and v) potential contaminant. Group 2 was further divided into Gram –ve and Gram +ve pathogens. Receiver operating characteristic (ROC) curves were constructed to compare the diagnostic performance of the biomarkers.ResultsThere were 1767 discreet patient admissions. The median PCT concentration differed significantly across blood culture groups (p < 0.0001). The highest median PCT concentration was observed in patients with a Gram-negative pathogen (17.1 ng/mL; IQR 3.6–49.7) and the lowest PCT in patients with negative blood cultures (0.6 ng/mL; IQR 0.2–2.8). The AUROC was 0.83 (0.79–0.86) for PCT, 0.68 (0.64–0.72) for the NLCR, 0.55 (0.51–0.60) for lactate concentration and 0.52 (0.48–0.57) for the WBC count. The AUROC for PCT was significantly greater than that of the NLCR (p < 0.0001). A PCT less than 0.5 ng/mL had a negative predictive value of 95% for excluding BSI. The best cut-off value of PCT for predicting BSI was 1.5 ng/ml.ConclusionOur results suggest that PCT of less than 0.5 ng/mL may be an effective screening tool to exclude BSI as the cause of sepsis, while the diagnosis of BSI should be considered in patients with a PCT above this threshold. The total WBC count and blood lactate concentration may not be reliable biomarkers for the diagnosis of BSI. The NLCR may be a useful screening test for BSI when PCT assays are not available.     

3项指标诊断老年菌血症的价值

目的探讨降钙素原(PCT)、C-反应蛋白(CRP)、白细胞计数(WBC)诊断年龄大于65岁的老年患者菌血症的价值。方法采用回顾性研究,对四川省人民医院年龄大于65岁疑似感染的1 688例住院患者检测PCT、CRP和WBC水平。结果 1 688例患者中菌血症患者275例。菌血症患者血清PCT和CRP水平较非菌血症患者高(P0.05)。在菌血症患者中,革兰阴性菌感染患者PCT水平高于革兰阳性菌感染患者,差异具有统计学意义(P0.05)。将患者按年龄分为老年组1(65~74岁)和老年组2(≥75岁)两个组,血清PCT、CRP水平在两组间差异有统计学意义(P0.05)。诊断菌血症,PCT的最适cut off值为1.30ng/mL,其特异度为77.69%,灵敏度为81.81%。CRP的cut off值为3.0mg/L时,灵敏度为97.45%。PCT诊断菌血症的ROC曲线下面积(AUC)为0.835(95%CI:0.809~0.860),优于CRP(AUC=0.608,95%CI:0.571~0.644)和WBC(AUC=0.531,95%CI:0.496~0.567),差异有统计学意义(P0.05)。结论对疑似菌血症的老年患者,PCT较CRP、WBC有更好的诊断效能,PCT可以作为预测老年菌血症患者的快速且可靠的指标。     

Procalcitonin reflects bacteremia and bacterial load in urosepsis syndrome: a prospective observational study

Introduction

Guidelines recommend that two blood cultures be performed in patients with febrile urinary tract infection (UTI), to detect bacteremia and help diagnose urosepsis. The usefulness and cost-effectiveness of this practice have been criticized. This study aimed to evaluate clinical characteristics and the biomarker procalcitonin (PCT) as an aid in predicting bacteremia.

Methods

A prospective observational multicenter cohort study included consecutive adults with febrile UTI in 35 primary care units and 8 emergency departments of 7 regional hospitals. Clinical and microbiological data were collected and PCT and time to positivity (TTP) of blood culture were measured.

Results

Of 581 evaluable patients, 136 (23%) had bacteremia. The median age was 66 years (interquartile range 46 to 78 years) and 219 (38%) were male. We evaluated three different models: a clinical model including seven bed-side characteristics, the clinical model plus PCT, and a PCT only model. The diagnostic abilities of these models as reflected by area under the curve of the receiver operating characteristic were 0.71 (95% confidence interval (CI): 0.66 to 0.76), 0.79 (95% CI: 0.75 to 0.83) and 0.73 (95% CI: 0.68 to 0.77) respectively. Calculating corresponding sensitivity and specificity for the presence of bacteremia after each step of adding a significant predictor in the model yielded that the PCT > 0.25 μg/l only model had the best diagnostic performance (sensitivity 0.95; 95% CI: 0.89 to 0.98, specificity 0.50; 95% CI: 0.46 to 0.55). Using PCT as a single decision tool, this would result in 40% fewer blood cultures being taken, while still identifying 94 to 99% of patients with bacteremia. The TTP of E. coli positive blood cultures was linearly correlated with the PCT log value; the higher the PCT the shorter the TTP (R² = 0.278, P = 0.007).

Conclusions

PCT accurately predicts the presence of bacteremia and bacterial load in patients with febrile UTI. This may be a helpful biomarker to limit use of blood culture resources.     

血清降钙素原水平在血流感染中的临床价值

目的探讨血清降钙素原(PCT)水平在血流感染患者中的临床价值。方法回顾性分析我院568例同时送检PCT检测和血培养的结果,其中有效研究对象538例;比较PCT水平与血培养结果的关系,同时比较PCT在革兰阴性菌、革兰阳性菌及真菌之间的差异;选取多次行PCT检测的血培养阳性患者,并依据3周内转归分为好转组、迁延组及死亡组,比较不同转归患者PCT差异。各组间PCT差异比较采用秩和检验;预后分析中采用Fisher’s精确概率法。结果血培养阳性患者PCT值[3.39(0.69~6.52)μg/L]明显高于血培养阴性患者[0.31(0.09~1.48)μg/L],差异有统计学意义(P0.05);G-菌、G+菌及真菌感染患者PCT分别为4.39(1.80~10.85)μg/L、1.98(0.42~4.05)μg/L及0.62(0.39~3.98)μg/L,差异有统计学意义(P0.05);根据受试者工作特征曲线(ROC),PCT临界值设定为3.315μg/L时,区分G-菌与真菌血流感染的灵敏度为67.9%,特异度为75.0%;设定为4.1μg/L时,PCT区分G+菌与G-菌血流感染的灵敏度为57.7%,特异度为76.5%;46例多次PCT检测血培养阳性患者中,PCT呈下降趋势时患者预后较好。结论血清PCT水平的检测有助于快速排除和诊断血流感染,同时有助于区分G-菌、G+菌及真菌所致的感染;动态监测PCT变化趋势有助于患者预后的判断。