Purohit Geetarani, Gaind Rajni, Dawar Reetika, Verma P K, Aggarwal K C, Sardana Raman, Deb Monorama
Senior Resident, Department of Microbiology, VMMC and Safdarjung Hospital, New Delhi, India.
Professor and Head, Department of Microbiology, VMMC and Safdarjung Hospital, New Delhi, India.
J Clin Diagn Res. 2017 Sep;11(9):DC01-DC05. doi: 10.7860/JCDR/2017/25988.10548. Epub 2017 Sep 1.
Enterococci are part of the normal intestinal flora and have been recognized as important human pathogens. Vancomycin Resistant Enterococci (VRE) are global threat as this resistance is transmissible and also poses a challenge for infection control.
This study was undertaken to study phenotypic and genotypic characteristics of VRE from clinically significant infections among hospitalized patients and their association with gut colonization.
Clinically significant isolates of enterococci (n=250) were studied. Species confirmation was done by Polymerase Chain Reaction (PCR). Minimum Inhibitory Concentration (MIC) for vancomycin was determined by E-test. PCR for and gene was done for genotypic characterization. MIC for teicoplanin, linezolid, tigecycline, daptomycin and quinupristin-dalfopristin was determined by E test. Patients with VRE infection were screened for gut colonization using vancomycin screen agar (6 μg/mL). Continuous data was analysed using the Student's t-test. Categorical data was assessed using Pearson's Chi-square test. A value of p ≤ 0.05 was considered statistically significant.
There was good correlation between the phenotypic and genotypic methods used for species identification and detection of vancomycin resistance. (162, 64.8%) was most common followed by (82, 32.84%) and (6, 2.4%). Overall higher resistance was observed among Vancomycin MIC ≥ 2 μg/mL was noted in 63 (25.2%) isolates. Fifty seven isolates showed presence of and was detected in six isolates of . Isolates with genotype was not detected in the present study. MIC (μg/mL) for teicoplanin, linezolid, tigecycline, daptomycin and quinupristin-dalfopristrin was 24, 0.75, 0.064, 2 and 0.064 respectively. Resistance to linezolid (1, 1.6%) and tigecycline (2, 3.2%) was rare. Majority (33/47, 70.2%) patients with clinically significant VRE infection showed gut colonization.
Vancomycin resistance among enterococci is emerging. Emergence of tigecycline and linezolid resistance is also posing a challenge for clinicians. Thus, further investigations are warranted to control vancomycin resistance among pathogens.
肠球菌是正常肠道菌群的一部分,已被公认为重要的人类病原体。耐万古霉素肠球菌(VRE)是全球面临的威胁,因为这种耐药性具有传播性,也给感染控制带来了挑战。
本研究旨在探讨住院患者临床显著感染中VRE的表型和基因型特征及其与肠道定植的关系。
对250株具有临床意义的肠球菌分离株进行研究。通过聚合酶链反应(PCR)进行菌种鉴定。采用E-test法测定万古霉素的最低抑菌浓度(MIC)。进行针对 和 基因的PCR以进行基因型鉴定。采用E-test法测定替考拉宁、利奈唑胺、替加环素、达托霉素和奎奴普丁-达福普汀的MIC。使用万古霉素筛选琼脂(6μg/mL)对VRE感染患者进行肠道定植筛查。连续数据采用学生t检验进行分析。分类数据采用Pearson卡方检验进行评估。p≤0.05的值被认为具有统计学意义。
用于菌种鉴定和检测万古霉素耐药性的表型和基因型方法之间具有良好的相关性。 (162株,64.8%)最为常见,其次是 (82株,32.84%)和 (6株,2.4%)。总体而言 在 中观察到更高的耐药性。63株(25.2%)分离株的万古霉素MIC≥2μg/mL。57株分离株显示存在 ,6株 分离株中检测到 。本研究未检测到具有 基因型的分离株。替考拉宁、利奈唑胺、替加环素、达托霉素和奎奴普丁-达福普汀的MIC(μg/mL)分别为24、0.75、0.064、2和0.064。对利奈唑胺(1株,1.6%)和替加环素(2株,3.2%)的耐药性罕见。大多数(33/47,70.2%)具有临床意义的VRE感染患者显示有肠道定植。
肠球菌中的万古霉素耐药性正在出现。替加环素和利奈唑胺耐药性的出现也给临床医生带来了挑战。因此,有必要进一步开展研究以控制病原体中的万古霉素耐药性。