Vijayakumar Ramraj, Giri Sidhartha, Kindo Anupma Jyoti
Department of Microbiology, Sri Ramachandra Medical College and Research Institute, Sri Ramachandra University, Porur, Chennai, India.
J Lab Physicians. 2012 Jan;4(1):1-4. doi: 10.4103/0974-2727.98661.
Candida spp is an emerging cause of blood stream infections worldwide. Delay in speciation of Candida isolates by conventional methods and resistance to antifungal drugs (especially fluconazole, amphotericin B, etc.) in various Candida species are some of the factors responsible for the increase in morbidity and mortality due to candidemia. So, the rapid detection and identification of Candida isolates from blood is very important for the proper management of patients having candidemia.
In this study, we have used polymerase chain reaction (PCR) - restriction fragment length polymorphism (RFLP) as a method for the speciation of Candida isolates from blood samples of intensive care unit (ICU) patients. PCR was used to amplify the ITS-1 and ITS-2 regions of Candida spp using universal primers ITS-1 and ITS-4. The amplified product was digested using Msp I restriction enzyme by RFLP.
The method PCR-RFLP helped in identifying five medically important Candida spp (C. tropicalis, C. albicans, C. parapsilosis, C. krusei and C. glabrata) from blood. This method is rapid, reliable, easy and cost-effective and can be used in routine laboratory diagnostics for the rapid identification of Candida isolates from blood.
PCR-RFLP is an easy, rapid and highly valuable tool which can be used in routine diagnostic laboratories to speciate Candida isolates obtained from blood. This rapid method of speciation will help clinicians to decide on empirical therapy in candidemia cases before antifungal susceptibility results are available.
念珠菌属是全球血流感染的一个新兴病因。通过传统方法对念珠菌分离株进行鉴定的延迟以及各种念珠菌属对抗真菌药物(尤其是氟康唑、两性霉素B等)的耐药性是导致念珠菌血症发病率和死亡率增加的一些因素。因此,从血液中快速检测和鉴定念珠菌分离株对于念珠菌血症患者的恰当治疗非常重要。
在本研究中,我们使用聚合酶链反应(PCR)-限制性片段长度多态性(RFLP)作为从重症监护病房(ICU)患者血液样本中鉴定念珠菌分离株种类的方法。使用通用引物ITS-1和ITS-4通过PCR扩增念珠菌属的ITS-1和ITS-2区域。扩增产物通过RFLP用Msp I限制性内切酶进行消化。
PCR-RFLP方法有助于从血液中鉴定出五种医学上重要的念珠菌属(热带念珠菌、白色念珠菌、近平滑念珠菌、克柔念珠菌和光滑念珠菌)。该方法快速、可靠、简便且具有成本效益,可用于常规实验室诊断以快速鉴定血液中的念珠菌分离株。
PCR-RFLP是一种简便、快速且极具价值的工具,可用于常规诊断实验室对从血液中获得的念珠菌分离株进行分类鉴定。这种快速的分类鉴定方法将有助于临床医生在获得抗真菌药敏结果之前,对念珠菌血症病例做出经验性治疗决策。