甲氧西林耐药的金黄色葡萄球菌感染一例并文献复习

Methicillin resistant Staphyloccus aureus infection： a case report and literature review

目的通过对1例金黄色葡萄球菌染色体基因盒（SCCmec）Ⅴ型的甲氧西林耐药的金黄色葡萄球菌（MRSA）感染病例的分析，增强对MRSA社区或医院获得性感染的认识。方法对2008年6月19日北京医院皮肤科收治、呼吸科会诊的1例SCCmec Ⅴ型的MRSA感染病例分离自血及痰标本的3株MRSA菌株进行培养及体外药物敏感试验。应用PCR方法对分离菌株进行甲氧西林耐药性决定因子A（mecA）基因鉴定和杀白细胞素（PVL）基因检测，应用多重PCR方法对其进行SCCmec分型。结果患者男，73岁，因剥脱性皮炎入院，病程中出现MRSA败血症，继之出现双侧肺炎，最终因感染性休克死亡。药物敏感试验结果显示，该MRSA菌株除对β-内酰胺类抗生素耐药外，对其他抗生素如克林霉素敏感，对莫西沙星、庆大霉素为中介性耐药。分离的3株MRSA均属于SCCmec Ⅴ型。结论该患者为医院获得性MRSA感染，但其菌株具有社区获得性MRSA的特点，临床医师应注意鉴别。

Objective To report a case of infection with methicillin resistant Staphyloccus aureus （MRSA） carrying Staphylococcal chromosome cassette mee（SCCmee） type V, and to identify the origin of the isolates. Methods A case of infection with MRSA carrying SCCmec type V was reported. The clinical characteristics of this patient were described. Screening for methicillin and other antibiotic resistant phenotypes by VITEK Ⅱ compact was carried out. PCR was used to determine the MRSA mecA gene, and multiplex PCR assay was used for characterization of SCCmec. Results The 73-year old male patient was admitted to our hospital for exfoliative dermatitis, but the condition got worse with sepsis and hospital acquired pneumonia, and finally the patient died of septic shock. The isolated Staphyloccus aureus from peripheral blood and sputum showed resistance to β-1actams alone, and susceptible to clindamycin, intermediate to moxifloxacin and gentamicin. The isolates were confirmed to be MRSA carrying SCCmec type Ⅴ. Conclusion A case of healthcare-acquired MRSA infection was identified, but the isolates also showed some characteristics of MRSA of the community origin.