新生儿社区获得性耐甲氧西林金黄色葡萄球菌皮肤软组织感染临床分离株的分子、耐药性及毒力特征研究

目的探讨新生儿社区获得性耐甲氧西林金黄色葡萄球菌（CA-MRSA）皮肤软组织感染临床分离株的分子、耐药性及毒力特征。方法从NICU中收集皮肤软组织感染的CA-MRSA菌株，总结其临床特点，对所有菌株进行MLST、SCCmec、SPA和agr分型，并行21种超抗原毒素基因、sasX基因和PVL基因检测。所有菌株进行体外药物敏感试验。结果28例CA-MRSA皮肤软组织感染的新生儿，单部位感染10例，多部位感染18例，检出30株CA-MRSA，以脐部蜂窝织炎为主（12/30,40.0%），主要的流行克隆为ST59-IVa-t437-agr-1（73%，22/30）, 超抗原毒力基因的携带率为80%，PVL的阳性率为47%。发现了4株苯唑西林敏感的MRSA（OS-MRSA），红霉素耐药率高。结论新生儿CA-MRSA皮肤软组织感染以脐部蜂窝织炎为主，主要的流行克隆为ST59-IVa-t437-agr-1, 超抗原及PVL基因携带率高，首次发现了OS-MRSA，红霉素耐药率高。

Molecular characteristics of antibiotic resistance and virulence in community acquired methicillin-resistant Staphylococcus aureus from neonates with skin and soft tissue infections

ObjectiveTo study the characteristics of the molecular, drug resistance and virulence in community acquired methicillin-resistant staphylococcus aureus from neonates with skin and soft tissue infections. MethodsCA-MRSA isolates were prospectively collected from Beijing Children's Hospital. All the isolates were characterized by staphylococcal chromosomal cassette (SCCmec) type, staphylococcal protein A (spa) type and multilocus sequence type (MLST). Superantigen toxin gene, sasX gene, antimicrobial susceptibility were also detected. ResultsCellulitis of umbilicus was the most common case, and the most common CA-MRSA clones were ST59-SCCmecIVa-t437. The sasX gene was not detected. Four isolates were oxacillin-susceptible. ConclusionCellulitis of umbilicus was the most common case in neonates with skin and soft tissue infections, and ST59-SCCmecIVa-t437 was the most common clones. OS-MRSA was reported for the first time.