社区和医院获得性血流感染的病原菌分布及感染途径调查

Investigation on the distribution of pathogenic bacteria from community and hospital acquired blood current infection and their routes of infection

目的比较社区和医院获得性血流感染的病原菌分布及耐药情况,并调查其感染途径。方法对诊断为血流感染的351例病例进行回顾性病原菌分布和耐药性分析。结果社区感染组分离出病原菌87株,阳性分离率为6.5%;医院感染组分离出病原菌264株,阳性分离率为13.1%。两组均以革兰阴性杆菌为主,分离菌株中未发现耐碳青霉烯类革兰阴性杆菌及耐万古霉素和利奈唑胺的革兰阳性球菌。医院感染组菌群分布较社区感染组广,多重耐药率高。医院感染组大肠埃希菌和肺炎克雷伯菌超广谱β-内酰胺酶(ESBLs)检出率(37.9%、25.0%)高于社区感染组(18.5%、21.4%),耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)和金黄色葡萄球菌检出率(77.8%、45.5%)亦高于社区感染组(46.2%、33.3%)。医院感染组主要的感染途径为血管内导管和尿道,社区感染组主要的感染途径为呼吸道和胆道。呼吸道、胆道、尿道、腹部、肠道为感染途径的病原菌以革兰阴性菌为主,皮肤伤口、血管内导管及不明途径的病原菌多为革兰阳性菌。结论医院感染组分离细菌的耐药率普遍高于社区感染组,临床医生可根据其感染途径选择碳青霉烯类、万古霉素或利奈唑胺经验性用药,待体外药物敏感性试验结果出来后及时调整用药。

Objective To compare the pathogenic bacterium distribution and their drug resistance situations from community and hospital acquired blood current infection,and to investigate their routes of infection.Methods The 351 blood current infection patients were investigated for pathogenic bacterium distribution and drug resistance retrospectively.Results A total of 87 strains were isolated from community acquired blood current infection,and 264 strains were isolated from hospital acquired blood current infection.Their positive rates were 6.5% and 1 3.1 %.Both of them were mainly Gram-negative bacilli.The strains resistant to carbapenem were not found.Gram-positive cocci was sensitive to vancomycin and linezolid.The pathogenic bacterium distribution from hospital acquired blood current infection and the multi-drug resistance rate were wider and higher than those from community acquired blood current infection.The detection rates of extended-spectrum beta-lactamases (ESBLs ) of Escherichia coli and Klebsiella pneumoniae (37.9% and 25.0%)from hospital acquired group were higher than those from community acquired group (1 8.5% and 21 .4%).The methicillin-resistant coagulase negative Staphylococci (MRCNS)and Staphylococcus aureus detection rates (77.8% and 45.5%)were higher than those from community acquired group (46.2% and 33.3%). The principal infection routes were intravascular catheter and urethra in hospital acquired group.The principal infection routes in community acquired group were respiratory tract and biliary tract.The pathogenic bacteria from respiratory tract,biliary tract,urethra,peritoneum and intestinal tract as the routes of infection were given priority to Gram-negative bacilli.The routes of infection through skin wound,intravascular catheter and unknown pathway mostly were Gram-positive cocci.Conclusions Generally,the resistance rate of hospital acquired group is higher than that of community acquired group.Based on the routes of infection,carbapenem,vancomycin or linezolid could be chosen,until drug susceptibility tests report.