Sancak Banu, Menemenlioğlu Dilek, Aydin Nazli Gürkan, Ergüven Sibel, Arikan Sevtap
Hacettepe Universitesi Tip Fakültesi, Mikrobiyoloji ve Klinik Mikrobiyoloji Anabilim Dali, Ankara.
Mikrobiyol Bul. 2008 Oct;42(4):635-44.
Candida krusei is inherently resistant to fluconazole and is an important pathogen responsible for nosocomial candidiasis especially in patients with hematological malignancy. Despite the growing clinical importance of C. krusei infections, little is known of its genetic diversity and molecular epidemiology. Therefore, differentiating between C. krusei isolates is of importance for a better understanding of the epidemiology, mode of transmission and pathogenesis of the organism. We investigated the use of two different methods (restriction endonuclease analysis of genomic DNA (REAG) with Hinfl and polymerase chain reaction by using Arno1 and Arno2 primers) for molecular typing of 56 C. krusei isolates from 56 patients. Ten different types (A-J) were determined by REAG. Depending on the patterns of isolates, the number of the bands varied from 12 to 15 and the size of the fragments varied from 2.0 kb to 6.2 kb. Of the isolates 71.4% were gathered under three major patterns (D, F, H). In the second method, PCR amplified different sizes of fragments varied approximately from 1 kb to 2 kb, which yielded 13 types (a-m) from 56 patients. Four major patterns (d, f, h, k) were observed for 58.9% of the isolates. The genotypes detected by REAG and PCR methods were found to be same in 43 isolates out of 56. As the banding patterns of the isolates were found to be similar in this study, it was thought that an exogenous origin could be the source of infections caused by C. krusei isolates. Both REA of genomic DNA and PCR analysis seem to be useful for the typing of C. krusei, however PCR assay can be preferred as it is a simple and rapid method. As a result, further studies are required for the validation of reproducibility and discriminatory power of these methods.
克鲁斯念珠菌对氟康唑天然耐药，是医院念珠菌病尤其是血液系统恶性肿瘤患者念珠菌病的重要病原体。尽管克鲁斯念珠菌感染的临床重要性日益增加，但其遗传多样性和分子流行病学却鲜为人知。因此，区分克鲁斯念珠菌分离株对于更好地了解该生物体的流行病学、传播方式和发病机制至关重要。我们研究了两种不同方法（用Hinfl进行基因组DNA的限制性内切酶分析（REAG）以及使用Arno1和Arno2引物进行聚合酶链反应）对56例患者的56株克鲁斯念珠菌分离株进行分子分型。通过REAG确定了10种不同类型（A-J）。根据分离株的图谱，条带数量从12条到15条不等，片段大小从2.0 kb到6.2 kb不等。71.4%的分离株归为三种主要图谱（D、F、H）。在第二种方法中，PCR扩增出大小约从1 kb到2 kb不等的不同片段，56例患者产生了13种类型（a-m）。58.9%的分离株观察到四种主要图谱（d、f、h、k）。在56株分离株中，有43株通过REAG和PCR方法检测到的基因型相同。由于本研究中分离株的条带图谱相似，因此认为外源来源可能是克鲁斯念珠菌分离株引起感染的源头。基因组DNA的REA和PCR分析似乎都可用于克鲁斯念珠菌的分型，然而PCR检测因其简单快速而更受青睐。因此，需要进一步研究以验证这些方法的可重复性和鉴别能力。
