Singh Surya K, Gupta K, Tiwari S, Shahi Shailesh K, Kumar S, Kumar A, Gupta Sanjeev K
Banaras Hindu University, Varanasi, India.
Int J Low Extrem Wounds. 2009 Dec;8(4):203-8. doi: 10.1177/1534734609353080.
The polymicrobial nature of diabetic foot infection is a reflection of the immune compromised state of the host.The methods of microbial identification based on colony morphology and biochemical characteristics have limitations as they may not differentiate the diverse microorganisms that infect foot wounds. The aim of the present study was to find out the bacterial diversity in diabetic foot infections at genetic level by finger printing, that is, ERIC-PCR (enterobacterial repetitive intergenic consensus -polymerase chain reaction). Nine patients with infected diabetic foot ulcers were recruited to the study. Pus and tissue samples were collected from the wound site. Aerobic bacteria were isolated employing standard microbiological culture methods and their genetic variability was analyzed using the ERIC-PCR. Sensitivity test for these isolates against commonly used antibiotics were performed using disc diffusion method. The standard microbiological culture technique yielded 38 morphotypes of bacteria and their genetic diversity was confirmed by ERIC-PCR assay. Analysis of the similarity index using NTSYSpc 2.1 software revealed 34 types of banding pattern among these isolates. Based on the similarity index these isolates were divided into 7 groups. As many as 8 types of aerobic bacterial isolates were detected from a single patient using the above technique compared with 2 on routine culture analysis. Genetically diverse isolates showed differential sensitivity pattern against commonly used antibiotics in the assay. The observed diversity at genetic level is attributed to variable sensitivity pattern of these isolates against the class of antibiotics. A molecular technique such as ERIC-PCR is a more sensitive detection method than conventional techniques, the potential of which needs to be fully understood.
糖尿病足感染的多微生物性质反映了宿主的免疫受损状态。基于菌落形态和生化特征的微生物鉴定方法存在局限性，因为它们可能无法区分感染足部伤口的各种微生物。本研究的目的是通过指纹识别，即肠杆菌重复基因间共有序列聚合酶链反应（ERIC-PCR），在基因水平上找出糖尿病足感染中的细菌多样性。九名患有感染性糖尿病足溃疡的患者被纳入该研究。从伤口部位采集脓液和组织样本。采用标准微生物培养方法分离需氧菌，并使用ERIC-PCR分析其遗传变异性。使用纸片扩散法对这些分离株进行针对常用抗生素的敏感性测试。标准微生物培养技术产生了38种细菌形态型，其遗传多样性通过ERIC-PCR分析得到证实。使用NTSYSpc 2.1软件分析相似性指数，揭示了这些分离株中有34种条带模式。基于相似性指数，这些分离株被分为7组。使用上述技术从一名患者中检测到多达8种需氧菌分离株，而常规培养分析仅检测到2种。基因多样化的分离株在测定中对常用抗生素表现出不同的敏感性模式。在基因水平上观察到的多样性归因于这些分离株对该类抗生素的可变敏感性模式。诸如ERIC-PCR之类的分子技术是一种比传统技术更敏感的检测方法，其潜力需要得到充分认识。
