血液病患者血流感染病原菌分布及耐药性分析

Analysis of the Distribution and Drug Resistance of Pathogenic Bacteria Causing Bloodstream Infection in Patients with Hematologic Disease

目的分析本院血液科住院患者血流感染病原菌的分布和耐药情况,为临床合理使用抗菌药物,减缓细菌耐药性产生提供依据.方法应用BACT/ALERT3D全自动血培养仪对临床送检的血培养标本进行培养,使用VITEK2 Compact全自动微生物分析系统对血培养阳性标本分离菌株进行菌种鉴定及药敏试验,应用WHONET 5.6软件对病原菌分布和药敏结果进行统计分析.结果2017年10月~2018年9月本院血液科住院患者血培养阳性标本中共分离病原菌101株,其中革兰阴性菌77株(76.24%),主要为大肠埃希菌、肺炎克雷伯菌和铜绿假单胞菌;革兰阳性菌23株(22.77%),主要为凝固酶阴性葡萄球菌(CNS)和金黄色葡萄球菌(金葡菌);真菌1株(0.99%),为热带假丝酵母菌.移植和非移植患者病原菌分布构成略有不同.产超广谱β-内酰胺酶(ESBLs)菌株在大肠埃希菌和肺炎克雷伯菌中的检出率分别为42.9%和55.0%.检出亚胺培南耐药的大肠埃希菌1株(2.9%),肺炎克雷伯菌3株(15%).铜绿假单胞菌对常用抗菌药物的耐药率均较低.6株金葡菌中检出耐甲氧西林金葡菌2株(33.3%).12株CNS中检出8株耐甲氧西林凝固酶阴性葡萄球菌(66.7%).主要革兰阳性菌对万古霉素、利奈唑胺、替加环素和奎奴普丁/达福普汀敏感率均达100%.结论本院血液科血流感染病原菌种类复杂多样、革兰阴性菌所占比例居多,且多重耐药菌检出率高,及时监测病原菌的菌属分布和耐药变迁,可指导临床合理、规范地使用抗菌药物.

Objective To explore the distribution and drug resistance of pathogens causing blood stream infection in patients with hematologic disease,to provide the evidence for rational antimicrobial therapy.Method The bioMerieux BACT/ALERT 3D system was used for blood culture.VITEK2 Compact system was uesed to indentify bacteria and antibiotic susceptibility.WHONET 5.6 software was uesed to analyze the distribution and drug resistance of pathogens.Results A total of 101 strains of pathogens were isolated from blood culture from October 2017 to September 2018,of which gram negative organisms accounted for 76.24%,gram positive cocci 22.77%and fungi 0.99%.The distribution of pathogens causing blood stream infection in patients with hematologic stem cell transplantation(HSCT)were different from patients without HSCT.The prevalence of ESBLs in E.coli and Klebsiella pneumoniae were 42.9%and 55.0%,respectively.P.aeruginosa strains were susceptible to commonly used antibiotics.1 strains of E.coli and 3 strains of Klebsiella pneumoniae were resistant to imipenem.The prevalence of methicillin-resistant strains was 33.3%in S.aureus(MRSA)and 66.7%in coagulase negative Staphylococcus(MRCNS).All Gram-positive bacilli were susceptible to vancomycin,linezolid,tegacycline and quinupristindalfopristin.Conclusion The pathogens isolated from patients with hematologic malignancies were mainly gram negative organisms.Moreover,the pathogens are highly resistant to multiple antibiotics.It is necessary to strengthen surveillance of bacterial resistance.Antimicrobial therapy should be decided cautiously base on local pathogen distribution and bacterial resistance.