肿瘤患者术后手术部位感染的病原菌分布及其耐药性研究

Analysis of pathogen spectrum and antimicrobial resistance in cancer patients after surgery

目的:调查我院近5年肿瘤患者术后手术部位感染的病原菌分布及其耐药性,为临床合理选用抗生素提供参考依据。方法:选取我院于2008年10月至2013年9月接受手术治疗的肿瘤患者750例,严格按《全国临床检验操作规程》进行细菌分离培养及鉴定和药敏试验,采用伤口拭子法采集标本,药敏试验采用纸片扩散法,分别对葡萄球菌属甲氧西林耐药株和肠杆菌科细菌产生的超广谱β-内酰胺酶(ESBLs)菌株进行检测,计算不同致病菌的耐药率和产耐药酶菌株的比例。结果:750例患者中共分离出病原菌845株,其中G-杆菌占64.85%(548/845),G+球菌占31.72%(268/845),G-杆菌和G+球菌分别以大肠埃希菌和凝固酶阴性的葡萄球菌为主;可产生超广谱β-内酰胺酶的大肠埃希菌和肺炎克雷伯菌比例分别为48.65%(72/148)和22.89%(19/83),阴沟肠杆菌产生高产头孢菌素酶(AmpC)的菌株占22.58%(14/62),铜绿假单胞菌产生金属β内酰胺酶的菌株占21.84%(19/87),甲氧西林耐药株分别占金黄色葡萄球菌和凝固酶阴性葡萄球菌的26.67%(20/75)和20.45%(18/88),未发现MRSA和MRCNS对万古霉素的耐药株;万古霉素和碳青霉烯类药物仍然分别是G+球菌和肠杆菌科细菌最敏感的药物。结论:本院肿瘤患者术后感染以G-杆菌为主;细菌耐药性以产生超广谱β内酰胺酶的大肠埃希菌和肺炎克雷伯菌、产AmpC酶的阴沟肠杆菌、产金属β内酰胺酶的铜绿假单胞菌、鲍曼不动杆菌、耐甲氧西林金黄色葡萄球菌和凝固酶阴性葡萄球菌比较严重,其他细菌也分别存在不同程度的耐药情况,临床微生物实验室应继续加强耐药性监测调查,为临床合理选用抗菌药物提供依据。

Objective：To explore pathogen spectrum and antimicrobial resistance in cancer patients after surgery.Methods：Selected 750 patients treated by surgery from October 2008 to September 2013 in our hospital.For bacteria isolation and identification and drug sensitivity test in strict accordance with the national clinical laboratory operation regulation.Samples were got by swab from infection site,extended-spectrum beta-lactamases and methicillin resistant strains of staphylococcus aureus were detected by disc diffusion confirmatory test.Results：845 bacterial strains were isolated from 750 infected patients,64.85 % （548/845） were gram-negative bacilli,and 31.72% （268/845） were gram-positive coccus.Escherichia coli and coagulase-negative staphylococci were the most common bacteria in G-bacilli and G＋ coccus respectively.The percentage of bacteria which could produce extended-spectrum beta -lactamases in escherichia coli and klebsiella pneumonia were 48.65 % （72/148） and 22.89% （19/83）,22.58% （14/62） of Enterobacter cloacae could produce AmpC,21.84% （19/87） of Pseudomonas aeruginosa could produce metal beta lactamase.The percentage of bacteria which resist to methicillin in staphylococcus aureus and coagulase negative staphylococcus were 26.67% （20/75） and 20.45% （18/88）,respectively.No MRSA or MRCNS were found resist to vancomycin.Conclusion：G-bacillus were the most common cause of postoperative infection in cancer patients of our hospital,the main resistance mechanism was to produce extended-spectrum beta-lactamases,AmpC and metal beta lactamase.