García-Elorriaga Guadalupe, Cortés-Torres Nancy, Ballesteros-Del-Olmo Julio César, Del Rey-Pineda Guillermo, Gonzáez-Bonilla César
Unidad de Investigaci6n en Inmunología e Infectología, Centro Medico Nacional La Raza, Instituto Mexicano del Seguro Social, México, D.F.
Rev Invest Clin. 2012 May-Jun;64(3):275-83.
In this study are evaluated the usefulness of the buffy coat smear and panbacterial polymerase chain reaction (PCR) as diagnostic tests in the early detection of neonatal sepsis.
It was studied 49 patients aged up to 28 days who were hospitalized in the Intensive Care Unit (ICUs) of the Neonatology, with a clinical diagnosis of neonatal sepsis and 49 umbilical cord samples of healthy newborns. Blood cultures and 50 microL of plasma were taken for the DNA and performance of the broad-range PCR primer system (panbacterial PCR). Simultaneously, were taken three capillaries with blood for the leukocyte layer (buffy coat) smear, we performed three stains: Gram; Löeffler blue methylene (LBM), and acridine orange (AO). Statistical analysis included sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) against the clinical diagnosis.
With respect to stains of buffy coat smear, they resulted very specific, from 90-97%, with 64-75% sensitivity, 87-94% PPV, and 77-82% NPV. In inverse fashion, PCR resulted very sensitive at 96%, with 91% specificity, 92% PPV, and 96% NPV.
Buffy coat smear stains are easy, fast, and specific, while that of PCR was highly sensitive. Thus, both can be utilized as diagnostic tests.
本研究评估了血沉棕黄层涂片和泛细菌聚合酶链反应（PCR）作为新生儿败血症早期诊断检测方法的实用性。
对49例年龄在28天以内、入住新生儿重症监护病房（ICU）且临床诊断为新生儿败血症的患者以及49例健康新生儿的脐带样本进行了研究。采集血培养样本和50微升血浆用于DNA提取及广谱PCR引物系统（泛细菌PCR）检测。同时，采集三根装有血液的毛细管用于制备白细胞层（血沉棕黄层）涂片，进行三种染色：革兰氏染色、吕弗勒亚甲蓝（LBM）染色和吖啶橙（AO）染色。针对临床诊断进行的统计分析包括敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）。
关于血沉棕黄层涂片染色，其特异性很高，为90% - 97%，敏感性为64% - 75%，PPV为87% - 94%，NPV为77% - 82%。相反，PCR的敏感性很高，为96%，特异性为91%，PPV为92%，NPV为96%。
血沉棕黄层涂片染色简便、快速且具有特异性，而PCR具有高度敏感性。因此，两者均可作为诊断检测方法。
