Abstract：
BACKGROUND: We aimed to identify patients at low risk of bloodstream infection (BSI) in the ED.
METHODS: We derived and validated a prediction model to rule out BSI in the ED without the need for laboratory testing by determining variables associated with a positive blood culture (BC) and assigned points according to regression coefficients. This retrospective study included adult patients suspected of having BSI (defined by at least one BC collection) from two European ED between 1 January 2017 and 31 December 2019. The primary end point was the BSI rate in the validation cohort for patients with a negative Bacteremia Rule Out Criteria (BAROC) score. The effect of adding laboratory variables to the model was evaluated as a second step in a two-step diagnostic strategy.
RESULTS: We analysed 2580 patients with a mean age of 64 years±21, of whom 46.1% were women. The derived BAROC score comprises 12 categorical clinical variables. In the validation cohort, it safely ruled out BSI without BCs in 9% (58/648) of patients with a sensitivity of 100% (95% CI 95% to 100%), a specificity of 10% (95% CI 8% to 13%) and a negative predictive value of 100% (95% CI 94% to 100%). Adding laboratory variables (creatinine ≥177 µmol/L (2.0 mg/dL), platelet count ≤150 000/mm3 and neutrophil count ≥12 000/mm3) to the model, ruled out BSI in 10.2% (58/570) of remaining patients who had been positive on the BAROC score. The BAROC score with laboratory results had a sensitivity of 100% (95% CI 94% to 100%), specificity of 11% (95% CI 9% to 14%) and negative predictive value of 100% (95% CI 94 to 100%). In the validation cohort, there was no evidence of a difference in discrimination between the area under the receiver operating characteristic for BAROC score with versus without laboratory testing (p=0.6).
CONCLUSIONS: The BAROC score safely identified patients at low risk of BSI and may reduce BC collection in the ED without the need for laboratory testing.
METHODS: We derived and validated a prediction model to rule out BSI in the ED without the need for laboratory testing by determining variables associated with a positive blood culture (BC) and assigned points according to regression coefficients. This retrospective study included adult patients suspected of having BSI (defined by at least one BC collection) from two European ED between 1 January 2017 and 31 December 2019. The primary end point was the BSI rate in the validation cohort for patients with a negative Bacteremia Rule Out Criteria (BAROC) score. The effect of adding laboratory variables to the model was evaluated as a second step in a two-step diagnostic strategy.
RESULTS: We analysed 2580 patients with a mean age of 64 years±21, of whom 46.1% were women. The derived BAROC score comprises 12 categorical clinical variables. In the validation cohort, it safely ruled out BSI without BCs in 9% (58/648) of patients with a sensitivity of 100% (95% CI 95% to 100%), a specificity of 10% (95% CI 8% to 13%) and a negative predictive value of 100% (95% CI 94% to 100%). Adding laboratory variables (creatinine ≥177 µmol/L (2.0 mg/dL), platelet count ≤150 000/mm3 and neutrophil count ≥12 000/mm3) to the model, ruled out BSI in 10.2% (58/570) of remaining patients who had been positive on the BAROC score. The BAROC score with laboratory results had a sensitivity of 100% (95% CI 94% to 100%), specificity of 11% (95% CI 9% to 14%) and negative predictive value of 100% (95% CI 94 to 100%). In the validation cohort, there was no evidence of a difference in discrimination between the area under the receiver operating characteristic for BAROC score with versus without laboratory testing (p=0.6).
CONCLUSIONS: The BAROC score safely identified patients at low risk of BSI and may reduce BC collection in the ED without the need for laboratory testing.
摘要：
背景：我们旨在确定ED中血流感染（BSI）风险较低的患者。
方法：我们推导并验证了一个预测模型，通过确定与血培养阳性（BC）相关的变量并根据回归系数分配点，在不需要实验室测试的情况下排除ED中的BSI。这项回顾性研究包括2017年1月1日至2019年12月31日期间来自两个欧洲ED的疑似患有BSI（由至少一个BC收集定义）的成年患者。主要终点是菌血症排除标准(BAROC)评分阴性患者的验证队列中的BSI率。作为两步诊断策略的第二步，评估了将实验室变量添加到模型中的效果。
结果：我们分析了2580名平均年龄为64岁±21岁的患者，其中46.1%为女性。导出的BAROC评分包括12个分类临床变量。在验证队列中，在9％（58/648）的敏感性为100％（95％CI95％至100％）的患者中，它安全地排除了无BCs的BSI，特异性为10%(95%CI8%至13%)，阴性预测值为100%(95%CI94%至100%)。添加实验室变量（肌酐≥177µmol/L（2.0mg/dL），血小板计数≤150000/mm3，中性粒细胞计数≥12000/mm3)，在其余10.2%(58/570)的BAROC评分阳性患者中排除了BSI.BAROC评分与实验室结果的敏感度为100%（95%CI94%至100%），特异性为11%(95%CI9%至14%)，阴性预测值为100%(95%CI94至100%)。在验证队列中，没有证据表明,接受实验室检测的BAROC评分的受试者工作特征下面积与未进行实验室检测的差异(p=0.6).
结论：BAROC评分可以安全地识别出BSI风险较低的患者，并且可以在不需要实验室检测的情况下减少ED中的BC收集。
方法：我们推导并验证了一个预测模型，通过确定与血培养阳性（BC）相关的变量并根据回归系数分配点，在不需要实验室测试的情况下排除ED中的BSI。这项回顾性研究包括2017年1月1日至2019年12月31日期间来自两个欧洲ED的疑似患有BSI（由至少一个BC收集定义）的成年患者。主要终点是菌血症排除标准(BAROC)评分阴性患者的验证队列中的BSI率。作为两步诊断策略的第二步，评估了将实验室变量添加到模型中的效果。
结果：我们分析了2580名平均年龄为64岁±21岁的患者，其中46.1%为女性。导出的BAROC评分包括12个分类临床变量。在验证队列中，在9％（58/648）的敏感性为100％（95％CI95％至100％）的患者中，它安全地排除了无BCs的BSI，特异性为10%(95%CI8%至13%)，阴性预测值为100%(95%CI94%至100%)。添加实验室变量（肌酐≥177µmol/L（2.0mg/dL），血小板计数≤150000/mm3，中性粒细胞计数≥12000/mm3)，在其余10.2%(58/570)的BAROC评分阳性患者中排除了BSI.BAROC评分与实验室结果的敏感度为100%（95%CI94%至100%），特异性为11%(95%CI9%至14%)，阴性预测值为100%(95%CI94至100%)。在验证队列中，没有证据表明,接受实验室检测的BAROC评分的受试者工作特征下面积与未进行实验室检测的差异(p=0.6).
结论：BAROC评分可以安全地识别出BSI风险较低的患者，并且可以在不需要实验室检测的情况下减少ED中的BC收集。
