Chan D K, Ho L Y
Department of Neonatology Singapore General Hospital, Singapore.
Singapore Med J. 1997 Jun;38(6):252-5.
Early diagnosis of sepsis in the neonate is often difficult because symptoms and signs are usually non-specific. A study was conducted to evaluate C-reactive protein (CRP) as a screening tool for neonatal sepsis among very low birth weight (VLBW) infants.
The study population consisted of 70 VLBW infants suspected of sepsis. Sepsis was diagnosed from positive cultures of blood, cerebro-spinal fluid or bone/joint aspirate in the presence of signs. Positive cultures were the "gold standard" against which the performance of CRP > or = 1.0 mg/dL, abnormal white cell counts (WCC), absolute neutrophil (ANC) and platelet counts were compared.
Of 152 septic screens, 30 (20%) had positive cultures. From analysis of the receiver operating characteristic (ROC) curve, CRP > or = 0.7 mg/dL rather than CRP > or = 1.0 mg/dL appeared a better cut-off for screening. The sensitivity, specificity, positive and negative predictive values of CRP > or = 0.7 mg/dL were 56%, 72%, 71% and 57% respectively. Only abnormal platelet counts had similar efficiency as CRP. Abnormal WCC had the lowest sensitivity and positive predictive value while abnormal ANC had the lowest specificity and negative predictive value among them.
CRP assay using laser nephelometry is a valuable adjunct in screening for neonatal sepsis, complementing clinical decision-making.
新生儿败血症的早期诊断通常较为困难,因为其症状和体征往往不具有特异性。本研究旨在评估C反应蛋白(CRP)作为极低出生体重(VLBW)婴儿新生儿败血症筛查工具的价值。
研究对象为70名疑似败血症的极低出生体重婴儿。在出现相关体征的情况下,通过血液、脑脊液或骨/关节穿刺液的阳性培养结果诊断败血症。阳性培养结果是“金标准”,据此比较CRP≥1.0mg/dL、白细胞计数(WCC)异常、绝对中性粒细胞(ANC)及血小板计数的诊断效能。
在152次败血症筛查中,30例(20%)培养结果呈阳性。通过对受试者工作特征(ROC)曲线分析,CRP≥0.7mg/dL而非CRP≥1.0mg/dL似乎是更好的筛查临界值。CRP≥0.7mg/dL的灵敏度、特异度、阳性预测值和阴性预测值分别为56%、72%、71%和57%。只有血小板计数异常与CRP具有相似的诊断效能。其中,白细胞计数异常的灵敏度和阳性预测值最低,而绝对中性粒细胞异常的特异度和阴性预测值最低。
采用激光散射比浊法检测CRP是新生儿败血症筛查中有价值的辅助手段,可辅助临床决策。