金黄色葡萄球菌的临床分布及耐药基因研究

A study on the clinical distribution of Staphylococcus aureus and its drug resistance genes

目的研究金黄色葡萄球菌的临床分布情况及耐药基因检出情况,为菌株感染的防治提供指导。方法收集835例2015年医院不同科室的住院患者送检标本,将患者送检标本进行金黄色葡萄球菌培养及分离纯化,采用细菌鉴定仪进行菌株鉴定,采用纸片扩散法分析金黄色葡萄球菌的药敏情况,并采用PCR检测耐药基因。结果从835例住院患者的临床标本中共分离金黄色葡萄球菌174株,其来源分别为脓液47株,分离率25.54%(47/184);痰液33株分离率21.43%(33/154);血液28株,分离率20.90%(28/134);分泌物21株,分离率18.58%(21/113);尿液19株,分离率19.19%(19/99);引流液12株,分离率16.67%(12/72);以及其他标本来源14株,分离率17.72%(14/79),各标本间金黄色葡萄球菌分离率差异无统计学意义(χ2=4.231,P=0.645)。174株金黄色葡萄球菌对阿米卡星、苯唑西林、四环素、红霉素、万古霉素、环丙沙星、替考拉宁、克林霉素、利福平和庆大霉素的耐药率分别为14.94%、39.08%、37.93%、59.20%、0.00%、31.03%、0.00%、47.70%、17.82%和45.98%。174株金黄色葡萄球菌mecA、qacA、ermA、ermB、ermC、aac(6')/aph(2')等耐药基因的阳性检出率分别为21.26%、10.92%、16.09%、35.06%、29.89%和43.10%。结论金黄色葡萄球菌广泛分布于医院感染患者脓液标本中,且在抗感染治疗中可以优先考虑使用万古霉素和替考拉宁,但是仍应合理选用;为控制菌株耐药性发生及发展,应及时检测耐药基因携带情况。

Objectives To study the clinical distribution of Staphylococcus aureus and to detect its drug resistance genes in order to guide the prevention and treatment of infections. Methods Samples were collected from 835 inpatients in different departments in 2015 and sent to the laboratory. S. aureus was cultured, isolated, and purified. The bacteria were identified by a microbe analyzer. The drug resistance of S. aureus was determined using disk diffusion, and drug re- sistance genes were detected using Results One hundred and seventy-four strains of S. aureus were isolated from the 835 clinical specimens from inpatients. Forty-seven strains were isolated from pus, 33 were isolated from sputum, 28 were isolated from blood, 21 were isolated from secretions, 19 were isolated from urine, 12 were isolated from drainage fluid, and 14 were isolated from other specimens. S. aureus was isolated from pus at a rate of 25.54% （47/184）, from sputum at a rate of 21. 43% （33/154）, from blood at a rate of 20.90% （28/134）, from secretions at a rate of 18.58% （21/113）, from urine at a rate of 19.19% （19/99）, from drainage fluid at a rate of 16.67% （12/72）, and from other types of specimens at a rate of 17.72 % （14/79）. The rate of S. aureus isolation did not differ significantly among the dif ferent types of specimens （x2 =4. 231, P=0. 645）. The 174 strains of S. aureus were resistant to amikacin at a rate of 14.94%, to oxacillin at a rate of 39.08%, to tetracycline at a rate of 37.93%, to erythromycin at a rate of 59.20%, to vancomycin at a rate of 0.00%, to ciprofloxacin at a rate of 31.03%, to teicoplanin at a rate of 0.00%, to clindamycin at a rate of 47.70%, to rifampicin at a rate of 17.82%, and to gentamicin at a rate of 45.98%. The mecA gene was detec ted in 174 strains of S. aureus at a rate of 21.26%, the qacA gene was detected at a rate of 10. 92%, the ermA gene was detected at a rate of 16.09%, the ermB gene was detected at a rate of 10.92%, the ermC gene was detected at a rate of 29.89%, and the aac （6＇）/aph （2＂） gene was detected at a rate of 43.10%. Conclusion S. aureus is widely distributed in pus samples from patients with a nosocomial infection. The use of vancomycin and teicoplanin should be prioritized when treating an infection, but those drugs should still be used rationally. The distribution of drug resistance genes should be promptly detected to control the occurrence and development of drug-resistant strains.