摘要
目的了解2003—2006年我院MRSA临床分离株中杀白细胞毒素(PVL)基因的分布、SCCmec分型、药物敏感性及其临床特征。方法对2003年1月至2006年12月我院1 366株MRSA临床分离菌株,用PCR方法筛选PVL基因阳性菌株,用多重PCR方法进行SCCmec分型;并进行回顾性研究,分析PVL基因阳性及阴性株所致感染的临床特点及相关危险因素;用琼脂稀释法测定其对临床常用抗菌药的敏感性(MIC)。结果在1 366株MRSA菌株中共筛出5株PVL基因阳性菌株,阳性率为0.37%。50株MRSA临床分离菌株中,SCCmecⅠ型1株,占2%(1/50);SCCmecⅡ型26株,占52%(26/50);SCCmecⅢ型16株(其中包括SCCmecⅢA1株),占32%(16/50);SCCmecⅣ型1株,占2%(1/50);SCCmecⅤ型2株,占4%(2/50);4株(8%)未能分型。5株PVL基因阳性株中SCCmecⅢ型1株,SCCmecⅣ型1株,SCCmecⅤ型2株,未分型1株。MIC结果显示PVL基因阳性株较阴性株对多种非β内酰胺类抗生素更为敏感,未发现万古霉素不敏感菌株。该5株PVL阳性菌株所致感染分别为皮肤软组织感染2例、肺部感染2例和尿路感染1例。结论PVL基因阳性MRSA已在我院检出,应加强医院感染控制防治其播散流行。
Objective Present study was designed to： （1） screen the methicillin resistant Staphylococcus aureus （MRSA） strains harboring PVL gene; （2） identify staphylococcal cassette chromosome mec （SCCmec） types of MRSA strains carrying PVL gene; （3） determine the susceptibilities of these strains to 14 antimicrobial agents; and （4） characterize the clinical feature and risk factor of the infections caused by these isolates. Methods One thousand three hundred and sixty six MRSA isolates from Huashan Hospital during 2003-2006 were included in this study. The detection of PVL genes was carried out by a PCR assay. To determine the types of SCCmec, multiplex polymerase chain reaction was performed. The minimal inhibitory concentration （MIC） of 14 antimicrobial agents were determined by agar dilution method. The clinical feature and risk factors were analyzed by retrospective method. Results The prevalence of PVL gene among clinical isolates of methicillin-resistant S. aureus was 0. 37 % （5/1 366）. The predominant SCCmec type found among the 50 MRSA isolates was SCCmec type Ⅱ （52%, 26/50）. SCCmec type Ⅲ was identified in 32% （16/50） of the isolates, SCCmec type V in 4% （2/50）. Four （8%） isolates were nontypable. Of the 5 PVL-positive MRSA, SCCmec type V was positive in 2 isolates, SCCmec type IV and type Ⅲ in one isolate each. The left one isolate was nontypable. The results of MIC showed that the MRSA isolates carrying PVL genes were more sensitive to various non-β-lactam antibiotics than the strains without PVL gene. No vancomycin resistant strain was found. These five PVL-positive isolates were responsible for skin and soft tissue infection （2 cases）, pulmonary infection （2 cases） and urinary tract infection （1 case）. Conclusions Isolates of PVL gene-positive MRSA have emerged in Huashan Hospital and measures should be taken to control its spread.
出处
《中国感染与化疗杂志》
CAS
2008年第3期167-171,共5页
Chinese Journal of Infection and Chemotherapy
基金
复旦大学基础临床交叉基金资助(JC07-19)
关键词
甲氧西林耐药金葡菌
聚合酶链反应
杀白细胞毒素基因
SCCmec分型
Methicillin-resistant Staphylococcus aureus
Polymerase chain reaction
Panton-Valentine leukocidin genes
Staphylococcal cassette chromosome mec typing
