某三甲教学医院老年患者血培养阳性分离菌的菌群分布及耐药性分析

Flora Distribution and Drug Resistance of the Bacteria Isolated from Positive Blood Culture in the Elderly in a 3 A Grade Teaching Hospital

目的分析某三甲教学医院老年患者血培养分离菌的菌群分布及耐药性。方法收集2018年1月-2019年3月复旦大学附属华东医院门急诊和住院老年患者的非重复送检血培养样本1 636份,其中男性患者1 041例,女性患者595例,平均年龄为(81.0±8.5岁)。血培养瓶报阳后转种,采用VITEKMS鉴定,并使用MIC法、纸片扩散法和E试验法进行体外药物敏感性试验。采用WHONET 5.6软件数据统计分析。结果剔除单侧报阳的凝固酶阴性葡萄球菌样本,和同一患者重复菌株后,共收集到173株分离菌,其中需氧菌占88.4%(153/173)、厌氧菌占1.2%(2/173)、真菌占10.4%(18/173),需氧菌中革兰阴性杆菌占64.7%(99/153),革兰阳性球菌占35.3%(54/153);主要来源科室为ICU23.7%(41/173)、普外科19.1%(33/173)和血液科9.2%(16/173)。大肠埃希菌对头孢曲松耐药率为63.6%,未发现对碳青霉烯类抗菌药物耐药株;肺炎克雷伯菌、鲍曼不动杆菌和铜绿假单胞菌对亚胺培南和美罗培南的耐药率依次为63.3%、33.3%和16.7%;在葡萄球菌和肠球菌中未检出万古霉素的耐药株,耐甲氧西林的金黄色葡萄球菌(MRSA)和凝固酶阴性的葡萄球菌(MRCNS)检出率为30%和89.5%。结论本研究血培养阳性样本中分离菌以革兰阴性杆菌为主,且分离菌对常用抗菌药物耐药率高。了解老年患者血培养分离菌的分布特征和耐药情况,有助于指导抗菌药物在老年患者血流感染中的合理应用。

Objective To analyze the flora distribution and drug resistance of the bacteria isolated from blood culture in the elderly patients in a 3 A grade hospital.Methods 1636 unrepeated blood culture samples of the elderly patients in a 3 A grade teaching hospital were collected during the period from January 2018 to March 2019,1041 from male cases and 595 from female cases,and the average of the elderly patients(81.0±8.5) years old;the pathogens were sub-cultured from the positive blood culture bottles and were identified by VITEK MS while.MIC method,disk diffusion test and E test were applied in testing the drug sensitivity;the statistical analysis was performed with software WHONET 5.6.Results A total of 173 isolates were collected,excluding the coagulase-negative Staphylococci sample that was positive for unilateral report and the repeated strains from the same case;the aerobic bacteria,the anaerobic bacteria and fungi accounted for 88.4%(153/173),1.2%(2/173) and 10.4%(18/173) respectively;among aerobic bacteria,Gram-negative bacilli and Gram-positive cocci accounted for 64.7%(99/153)and 35.3%(54/153) respectively;the main source departments were ICU(23.7%,41/173),department of general surgery(19.1%,(33/173) and department of hematology(9.2%,16/173);the resistance rate of Escherichia coli to ceftriaxone was63.6%;no carbapenem-resistant strains were detected;the resistance rates of Klebsiella,pneumoniae,Acinetobacter.baumannii and Pseudomonas aeruginosa to imepenam and meropenem were 63.3%,33.3% and 16.7% respectively;no vancomycin-resistant strains were detected in Staphylococci and Enterococci;the detection rate of methicillin-resistant Staphylococcus aureus(MRSA)was 30% and that of coagulase-negative staphylococci(MRCNS) was 89.5%.Conclusions Gram-negative bacilli are the main bacteria of positive blood culture bottle of the elderly patients in the 3 A grade hospital,and the isolates have high resistance to common antibiotics;a better understanding of the distribution characteristics and drug resistance of blood culture isolates in the elderly is of great help to lead a rational application of antibiotics in the elderly with bloodstream infection.