摘要
目的分析医院患者送检标本耐甲氧西林金黄色葡萄球菌分离情况及其毒力基因检测情况,为预防医院感染的发生和控制病原菌感染扩散提供指导。方法收集住院患者(住院时间>48h)送检标本,包括痰液、脓液、血液、分泌物、穿刺液、尿液以及导管标本等,分离耐甲氧西林金黄色葡萄球菌,采用K-B法和PCR扩增法进行菌株的耐药性分析及毒力基因检测。结果共分离133株耐甲氧西林金黄色葡萄球菌,分别来自患者的痰液(占61.65%)、脓液(占12.03%)、血液(占12.03%)、分泌物(占6.02%)、穿刺液(占3.76%)、尿液(占3.01%)以及导管(占1.50%)。K-B法药敏试验测定,133株耐甲氧西林金黄色葡萄球菌对苯唑西林、头孢曲松、庆大霉素、亚胺培南、四环素、环丙沙星、万古霉素的耐药率分别为100%、85.71%、73.68%、62.41%、51.13%、42.86%和0,PCR检测133株耐甲氧西林金黄色葡萄球菌的pvl、fnbA、clfA、sec、tst和sasX基因阳性率分别为88.72%、60.15%、42.11%、7.52%、4.51%和0。结论耐甲氧西林金黄色葡萄球菌多数分离自患者的痰液标本,以呼吸道感染为主。耐甲氧西林金黄色葡萄球菌对苯唑西林100%耐药,可能与菌株自身生物膜的形成能力以及菌株毒力的降低关系密切;耐甲氧西林金黄色葡萄球菌的各种毒力因子呈现出不同的分布特征,可能与分离株的标本来源、遗传背景差异性等有关,而其耐药性变化与菌株毒力变化之间的相关性仍需进一步证实。
Objectives To analyze methicillin-resistant Staphylococcus aureus isolated from hospital patients and to analyze its virulence genes in order to provide scientific guidance to prevent nosocomial infections and control the spread of that pathogen. Methods Samples,including sputum,pus,blood,secretions,aspirated fluid,urine,and catheter specimens,were collected from inpatients（duration of hospitalization 48h）and sent to the clinical laboratory of this Hospital.One hundred and thirty-three strains of methicillin-resistant S.aureus were isolated.The drug resistance of the strains was analyzed using the K-B method and virulence genes were detected via amplification with PCR.Results Of the133 strains of methicillin-resistant S.aureus that were isolated,61.65% were from sputum samples,12.03% were from pus samples,12.03% were from blood samples,6.02% were from secretions,3.76% were from aspirated fluid,3.01%were from urine samples,and 1.50% were from catheter specimens.Drug sensitivity testing revealed the resistance to oxacillin was 100%,resistance to ceftriaxone was 85.71%,resistance to gentamycin was 73.68%,resistance to imipenem was 62.41%,resistance to tetracycline was 51.13%,resistance to ciprofloxacin was 42.86%,and resistance to vancomycin was 0.0%.This indicates that the strains are most resistant to oxacillin but sensitive to vancomycin.The isolated strains had different levels of resistance to other antimicrobial agents.Of the 133 strains of methicillin-resistant S.aureus,88.72% had the pvl gene,60.15% had the fnbA gene,42.11% had the clfA gene,7.52% had the sec gene,4.51% had the tst gene,and 0.0% had the sasX gene according to PCR. Conclusion Methicillin-resistant S.aureus was mainly isolated from sputum samples,indicating that the type of infection was most often a respiratory tract infection.Methicillin-resistant S.aureus was most resistant to oxacillin.This finding might be closely related to the bacterium＇s ability to form a biofilm and to ways to reduce the virulence of strains.Virulence factors of
出处
《中国病原生物学杂志》
CSCD
北大核心
2015年第10期931-935,共5页
Journal of Pathogen Biology
关键词
耐甲氧西林金黄色葡萄球菌
毒力基因
PCR扩增
药敏试验
Methicillin-resistant Staphylococcus aureus
virulence genes
PCR amplification
drug sensitivity test
