Departments of Emergency Medicine and Pediatrics, University of California, Davis School of Medicine, Sacramento.
Division of Emergency Medicine, Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, New York.
JAMA Pediatr. 2019 Apr 1;173(4):342-351. doi: 10.1001/jamapediatrics.2018.5501.
In young febrile infants, serious bacterial infections (SBIs), including urinary tract infections, bacteremia, and meningitis, may lead to dangerous complications. However, lumbar punctures and hospitalizations involve risks and costs. Clinical prediction rules using biomarkers beyond the white blood cell count (WBC) may accurately identify febrile infants at low risk for SBIs.
To derive and validate a prediction rule to identify febrile infants 60 days and younger at low risk for SBIs.
DESIGN, SETTING, AND PARTICIPANTS: Prospective, observational study between March 2011 and May 2013 at 26 emergency departments. Convenience sample of previously healthy febrile infants 60 days and younger who were evaluated for SBIs. Data were analyzed between April 2014 and April 2018.
Clinical and laboratory data (blood and urine) including patient demographics, fever height and duration, clinical appearance, WBC, absolute neutrophil count (ANC), serum procalcitonin, and urinalysis. We derived and validated a prediction rule based on these variables using binary recursive partitioning analysis.
Serious bacterial infection, defined as urinary tract infection, bacteremia, or bacterial meningitis.
We derived the prediction rule on a random sample of 908 infants and validated it on 913 infants (mean age was 36 days, 765 were girls [42%], 781 were white and non-Hispanic [43%], 366 were black [20%], and 535 were Hispanic [29%]). Serious bacterial infections were present in 170 of 1821 infants (9.3%), including 26 (1.4%) with bacteremia, 151 (8.3%) with urinary tract infections, and 10 (0.5%) with bacterial meningitis; 16 (0.9%) had concurrent SBIs. The prediction rule identified infants at low risk of SBI using a negative urinalysis result, an ANC of 4090/µL or less (to convert to ×109 per liter, multiply by 0.001), and serum procalcitonin of 1.71 ng/mL or less. In the validation cohort, the rule sensitivity was 97.7% (95% CI, 91.3-99.6), specificity was 60.0% (95% CI, 56.6-63.3), negative predictive value was 99.6% (95% CI, 98.4-99.9), and negative likelihood ratio was 0.04 (95% CI, 0.01-0.15). One infant with bacteremia and 2 infants with urinary tract infections were misclassified. No patients with bacterial meningitis were missed by the rule. The rule performance was nearly identical when the outcome was restricted to bacteremia and/or bacterial meningitis, missing the same infant with bacteremia.
We derived and validated an accurate prediction rule to identify febrile infants 60 days and younger at low risk for SBIs using the urinalysis, ANC, and procalcitonin levels. Once further validated on an independent cohort, clinical application of the rule has the potential to decrease unnecessary lumbar punctures, antibiotic administration, and hospitalizations.
在发热的婴儿中，严重细菌感染（SBI），包括尿路感染、菌血症和细菌性脑膜炎，可能导致危险的并发症。然而，腰椎穿刺和住院治疗涉及风险和成本。使用白细胞计数（WBC）以外的生物标志物的临床预测规则可能能够准确识别 SBI 风险较低的发热婴儿。
制定并验证一种预测规则，以识别 60 天及以下发热婴儿 SBI 风险较低的情况。
设计、地点和参与者：这是一项 2011 年 3 月至 2013 年 5 月在 26 个急诊科进行的前瞻性、观察性研究。选择了之前健康的发热 60 天及以下的便利样本，以评估 SBI。数据在 2014 年 4 月至 2018 年 4 月之间进行了分析。
临床和实验室数据（血液和尿液），包括患者人口统计学、发热高度和持续时间、临床外观、WBC、绝对中性粒细胞计数（ANC）、血清降钙素原和尿液分析。我们使用二元递归分区分析基于这些变量制定和验证了预测规则。
严重细菌感染，定义为尿路感染、菌血症或细菌性脑膜炎。
我们在 908 名随机婴儿中推导了预测规则，并在 913 名婴儿中进行了验证（平均年龄为 36 天，765 名女孩[42%]，781 名白人非西班牙裔[43%]，366 名黑人[20%]，535 名西班牙裔[29%]）。1821 名婴儿中有 170 名（9.3%）发生严重细菌感染，包括 26 名（1.4%）菌血症、151 名（8.3%）尿路感染和 10 名（0.5%）细菌性脑膜炎；16 名（0.9%）并发 SBI。该预测规则使用阴性尿液分析结果、ANC 为 4090/µL 或更低（要转换为每升×109，乘以 0.001）和血清降钙素原 1.71ng/mL 或更低，确定 SBI 风险较低的婴儿。在验证队列中，该规则的灵敏度为 97.7%（95%CI，91.3-99.6），特异性为 60.0%（95%CI，56.6-63.3），阴性预测值为 99.6%（95%CI，98.4-99.9），阴性似然比为 0.04（95%CI，0.01-0.15）。一名菌血症婴儿和两名尿路感染婴儿被误诊。该规则未漏诊任何细菌性脑膜炎患儿。当将结局限制为菌血症和/或细菌性脑膜炎时，规则的性能几乎相同，漏诊了同一名菌血症患儿。
我们使用尿液分析、ANC 和降钙素原水平制定并验证了一种准确的预测规则，以识别 60 天及以下发热婴儿中 SBI 风险较低的婴儿。一旦在独立队列中进一步验证，该规则的临床应用有可能减少不必要的腰椎穿刺、抗生素治疗和住院治疗。
