Regional Neonatal Unit, St George's Hospital, London, UK.
Acta Paediatr. 2010 Nov;99(11):1691-4. doi: 10.1111/j.1651-2227.2010.01899.x. Epub 2010 Jun 17.
Meticillin-resistant staphylococcus aureus (MRSA) colonization on neonatal units is a common and important clinical problem. Effectiveness of polymerase chain reaction (PCR) for detecting MRSA nasal colonization of infants was evaluated and compared to culture-based methods. The effect of skin decolonization in affected infants was studied.
Paired nasal swabs were collected from infants in our neonatal unit over a 12-month period (September 2007-2008). Colonization with MRSA was determined with a commercially available PCR method and compared to culture.
A total of 696 paired nasal swabs were taken. Three infants were colonized at the beginning and were included. There were positive PCRs in 12 infants. Five infants cultured MRSA from a nasal swab at the same time. No infants were culture-positive when PCR was negative (sensitivity 100%, specificity 99% compared to culture). PCR results were available within 24 h. Five infants were PCR+ and isolated meticillin-sensitive Staphylococcus aureus. This organism gave a false-positive PCR result. Two infants transferred in on broad-spectrum antibiotics were PCR+ and negative by culture. Decolonization led to negative nasal PCR and culture in 4/5 infants to discharge.
PCR methods are sensitive and specific for detection of MRSA colonization in newborn infants of all gestations with results 1-2 days before culture.
耐甲氧西林金黄色葡萄球菌(MRSA)在新生儿病房的定植是一个常见且重要的临床问题。本研究旨在评估聚合酶链反应(PCR)检测婴儿鼻腔 MRSA 定植的有效性,并与基于培养的方法进行比较,同时还研究了对受影响婴儿进行皮肤去定植的效果。
在 2007 年 9 月至 2008 年 12 月期间,对我院新生儿病房的婴儿连续采集了 12 个月的成对鼻腔拭子。采用市售的 PCR 方法检测 MRSA 定植,并与培养方法进行比较。
共采集了 696 对鼻腔拭子。有 3 例婴儿定植于研究开始时被纳入研究,共有 12 例婴儿 PCR 阳性。5 例婴儿同时从鼻腔拭子中培养出 MRSA。当 PCR 阴性时,无婴儿培养阳性(与培养相比,敏感性为 100%,特异性为 99%)。PCR 结果可在 24 小时内获得。5 例 PCR+的婴儿分离出对甲氧西林敏感的金黄色葡萄球菌,该菌可导致假阳性 PCR 结果。2 例转入的婴儿广谱抗生素治疗,培养阴性而 PCR 阳性。4/5 例婴儿去定植后,鼻腔 PCR 和培养均转为阴性,得以出院。
对于所有胎龄的新生儿,PCR 方法对 MRSA 定植的检测均具有敏感性和特异性,且结果可在培养之前 1-2 天获得。