Carman and Ann Adams Department of Pediatrics, Children's Hospital of Michigan, Wayne State University, Detroit, MI; Department of Emergency Medicine, Wayne State University, Detroit, MI.
Acad Emerg Med. 2014 Feb;21(2):171-9. doi: 10.1111/acem.12316.
There is no perfectly sensitive or specific test for identifying young, febrile infants and children with occult serious bacterial infections (SBIs). Studies of procalcitonin (PCT), a 116-amino-acid precursor of the hormone calcitonin, have demonstrated its potential as an acute-phase biomarker for SBI. The objective of this study was to compare performance of serum PCT with traditional screening tests for detecting SBIs in young febrile infants and children.
This was a prospective, multicenter study on a convenience sample from May 2004 to December 2005. The study was conducted in four emergency departments (EDs): one pediatric ED and three EDs with pediatric units, all with academic faculty on staff. A total of 226 febrile children 36 months old or younger who presented to the four participating EDs and were evaluated for SBI by blood, urine, and/or cerebral spinal fluid (CSF) cultures were included.
The test characteristics (with 95% confidence intervals [CIs]) of the white blood cell (WBC) counts including neutrophil and band counts were compared with PCT for identifying SBI. Thirty children had SBIs (13.3%, 95% CI = 8.85 to 17.70). Four (13.3%) had bacteremia (including one with meningitis), 18 (60.0%) had urinary tract infections (UTIs), and eight (26.6%) had pneumonia. Children with SBIs had higher WBC counts (18.6 × 10(9) ± 8.6 × 10(9) cells/L vs. 11.5 × 10(9) ± 5.3 × 10(9) cells/L, p < 0.001), higher absolute neutrophil counts (ANCs; 10.6 × 10(9) ± 6.7 × 10(9) cells/L vs. 5.6 × 10(9) ± 3.8 × 10(9) cells/L, p = 0.009), higher absolute band counts (0.90 × 10(9) ± 1.1 × 10(9) cells/L vs. 0.35 × 10(9) ± 0.6 × 10(9) cells/L, p = 0.009), and higher PCT levels (2.9 ± 5.6 ng/mL vs. 0.4 ± 0.8 ng/mL, p = 0.021) than those without SBIs. In a multivariable logistic regression analysis, the absolute band count and PCT were the two screening tests independently associated with SBI, although the area under the receiver operating characteristic (ROC) curve for PCT was the largest (0.80, 95% CI = 0.71 to 0.89).
Procalcitonin is a more accurate biomarker than traditional screening tests for identifying young febrile infants and children with serious SBIs. Further study on a larger cohort of young febrile children is required to definitively determine the benefit of PCT over traditional laboratory screening tests for SBIs.
目前还没有一种完全敏感或特异的检测方法可以用于确定有隐匿性严重细菌感染（SBI）的发热婴幼儿。降钙素原（PCT）作为激素降钙素的 116 个氨基酸前体，其作为 SBI 的急性相生物标志物的潜力已得到研究证实。本研究旨在比较 PCT 与传统筛查试验对发热婴幼儿 SBI 的检测性能。
这是一项 2004 年 5 月至 2005 年 12 月间进行的前瞻性、多中心、便利样本研究。该研究在四个急诊部（ED）开展：一家儿科 ED 和三家设有儿科病房的 ED，这些 ED 均有在职的学术教员。共有 226 名发热 36 个月以下的儿童在这四个参与的 ED 就诊，他们的 SBI 通过血、尿和/或脑脊液（CSF）培养进行评估。
白细胞（WBC）计数包括中性粒细胞和带细胞计数的检测特征（95%置信区间 [CI]）与 PCT 用于识别 SBI 进行了比较。30 名儿童患有 SBI（13.3%，95%CI=8.85 至 17.70）。4 名（13.3%）患有菌血症（包括 1 名伴脑膜炎），18 名（60.0%）患有尿路感染（UTI），8 名（26.6%）患有肺炎。患有 SBI 的儿童的 WBC 计数更高（18.6×109±8.6×109细胞/L vs. 11.5×109±5.3×109细胞/L，p<0.001），绝对中性粒细胞计数（ANC；10.6×109±6.7×109细胞/L vs. 5.6×109±3.8×109细胞/L，p=0.009）和绝对带细胞计数（0.90×109±1.1×109细胞/L vs. 0.35×109±0.6×109细胞/L，p=0.009）更高，PCT 水平也更高（2.9±5.6 ng/mL vs. 0.4±0.8 ng/mL，p=0.021）。在多变量逻辑回归分析中，绝对带细胞计数和 PCT 是与 SBI 独立相关的两项筛查试验，尽管 PCT 的受试者工作特征（ROC）曲线下面积最大（0.80，95%CI=0.71 至 0.89）。
降钙素原是一种比传统筛查试验更准确的生物标志物，可用于确定有隐匿性严重 SBI 的发热婴幼儿。需要对更大队列的发热婴幼儿进行进一步研究，以明确 PCT 相对于传统实验室筛查试验在 SBI 中的优势。
