Department of Mother and Child, University of Palermo, Palermo, Italy.
BMC Pediatr. 2012 Jun 8;12:64. doi: 10.1186/1471-2431-12-64.
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has recently emerged as an important pathogen in neonatal intensive care units (NICUs). The purposes of this study were to characterize methicillin-resistant isolates from an outbreak in a NICU, to examine the genetic traits and clonality of CA-MRSA, and to review the characteristics and outcomes of the neonatal cases and investigate the routes of entry and transmission of the MRSA outbreak strain in the NICU under study.
The study NICU practiced an active surveillance program for multidrug-resistant organisms, including weekly cultures for detection of MRSA from nasal swabs among all the admitted neonates. All first isolates from surveillance cultures and all clinical isolates were submitted for susceptibility testing and genotyping. Data from each infant's medical records were prospectively included in a database, and the clinical features and outcomes of the colonized/infected infants were assessed.
A total of 14 infants were colonized or infected by a strain of ST1-MRSA-IVa between April and August 2011. The CA-MRSA strain appeared to have been introduced to the NICU by an infected infant transferred from another hospital. The outbreak was successfully contained by multifaceted infection control interventions.
The results of this study confirm that NICU is a healthcare setting with a critical permeability to CA-MRSA. Active surveillance including molecular typing can help to detect and monitor the spread of antimicrobial drug-resistant organisms, and thus trigger timely control interventions.
社区相关性耐甲氧西林金黄色葡萄球菌（CA-MRSA）最近已成为新生儿重症监护病房（NICU）中的一种重要病原体。本研究的目的是对 NICU 中暴发的耐甲氧西林金黄色葡萄球菌进行分离鉴定，分析 CA-MRSA 的遗传特征和克隆性，并回顾新生儿病例的特征和结局，同时调查研究中 NICU 中耐甲氧西林金黄色葡萄球菌暴发菌株的传入途径和传播方式。
研究 NICU 实施了针对多药耐药菌的主动监测计划，包括每周对所有入院新生儿进行鼻拭子 MRSA 检测。所有监测培养物中的首次分离株和所有临床分离株均进行药敏试验和基因分型。每位婴儿的病历数据均前瞻性地纳入数据库，评估定植/感染婴儿的临床特征和结局。
2011 年 4 月至 8 月期间，共有 14 名婴儿被 ST1-MRSA-IVa 定植或感染。CA-MRSA 菌株似乎是由从另一家医院转来的感染婴儿带入 NICU 的。通过采取多种感染控制干预措施，成功遏制了此次暴发。
本研究结果证实，NICU 是一个对 CA-MRSA 具有高度易感性的医疗机构。主动监测包括分子分型有助于发现和监测抗菌药物耐药菌的传播，并及时采取控制措施。
