2015年临床常见分离菌分布及耐药特性分析

Survey analysis of distribution and resistance profi les of common clinical bacteria in the year 2015

目的分析南昌大学第二附属医院2015年临床分离菌的分布构成及其对常用抗菌药物的耐药特性。方法收集我院2015年全年临床分离菌,剔除重复菌株,采用纸片扩散法或自动化仪器法进行药物敏感性试验,E试验法检测葡萄球菌对万古霉素及肺炎链球菌对青霉素的最低抑菌浓度(minimum inhibitory concentration,MIC)。依据美国临床实验室标准化协会(CLSI)2015年版标准判断结果,用WHONET 5.6软件进行数据分析。结果收集细菌3955株,其中革兰阳性菌1364株(34.5%),革兰阴性菌2591株(65.5%)。位列前5位的细菌依次为大肠埃希菌(18.9%)、金黄色葡萄球菌(12.0%)、肺炎克雷伯菌(11.4%)、铜绿假单胞菌(9.4%)和鲍曼不动杆菌(7.1%)。耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)检出率分别为23.5%和71.4%。91.0%MRSA对复方磺胺甲噁唑敏感,82.9%MRCNS对利福平敏感,均未发现万古霉素和利奈唑胺耐药株。屎肠球菌对绝大多数抗菌药物的耐药率显著高于粪肠球菌,检出2株万古霉素耐药屎肠球菌,未发现利奈唑胺耐药株。肺炎链球菌非脑膜炎菌株对青霉素耐药率为7.2%。大肠埃希菌和克雷伯菌属(肺炎克雷伯菌、产酸克雷伯菌)中产超广谱β-内酰胺酶(ESBL)株分别占62.1%和31.7%。鲍曼不动杆菌、铜绿假单胞菌和肺炎克雷伯菌对亚胺培南耐药率分别79.4%、17.0%和12.3%。结论细菌耐药现象仍较严重,特别是对碳青霉烯类耐药的鲍曼不动杆菌和肺炎克雷伯菌,感染控制部门应引起重视,积极采取有效的感染控制措施,临床应根据药敏结果科学合理选用抗菌药物。

Objective To analyze the distribution and resistance of clinical isolates in the Second Affiliated Hospital of Nanchang University in 2015.Methods Non-duplicated clinical isolates were collected during the full year of 2015.Antimicrobial susceptibility testing was carried out usingthe Kirby-Bauer method or automated systems.The minimum inhibitory concentrations（MICs） of vancomycin for Staphylococcus spp.and penicillin for S.pneumoniae were determined by E-test.The data were analyzed using the WHONET 5.6 software and judged according to the Clinical and Laboratory Standards Institute guideline 2015.Results A total of 3955 non-duplicated clinical isolates,of which Gram-positive and Gram-negative bacteria accounted for 34.5% （1364） and 65.5% （2591） respectively.The top five bacterial species were Escherichia coli,Staphylococcus aureus,Klebsiella pneumoniae,Pseudomonas aeruginosa,and Acinetobacter baumannii,accounting for 18.9%,12.0%,11.4%,9.4%,7.1%.Methicillin-resistant strains in S.aureus （MRSA） and coagulase-negative Staphylococcus （MRCNS） accounted for 23.5% and 71.4%,respectively.91.0% of MRSA strains were susceptible to trimethoprim-sulfamethoxazole,while 82.9% of MRCNS were susceptible to rifampin.Staphylococcus strains resistant to vancomycin or linezolid were not detected.The resistance rates of E.faecium strains to most tested antimicrobial were much higher than those of E.faecalis.No strains of Enterococcus were found resistant to linezolid,and two strains of E.faecium were resistant to vancomycin.The prevalence of penicillin-resistant non-meningitis S.pneumoniae strains were 7.2%.Extended spectrum β-lactamases-producing strains （ESBLs） accounted for 62.1% and 31.7% in E.coli and Klebsiella spp.（K.pneumoniae and K.oxytoca）,respectively.12.3% of K.pneumoniae strains were resistant to imipenem.About 79.4% ofAcinetobacter baumannii,17.0% ofPseudomonas aeruginosa,and 12.3% ofK.pneumoniae were resistant to imipenem.Conclusion The antibiotic resistance of clinical bacterial isolates is still a serious phenomenon,and particularly Acinetobacter baumannii and K.pneumonia were resistant to carbapenems.Staffinthe department of infection control should pay attention to this problem and actively take effective measures.Clinical practice should be scientific and promote rational use of antibiotics according to the results of susceptibility tests.