Krutova Marcela, Matejkova Jana, Nyc Otakar
Department of Medical Microbiology, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital, V Uvalu 84, 150 06, Prague 5, Czech Republic,
Folia Microbiol (Praha). 2014 Nov;59(6):523-6. doi: 10.1007/s12223-014-0323-5. Epub 2014 Jun 27.
Clostridium difficile is a major nosocomial pathogen of present times. The analysis of 624 C. difficile strains from 11 hospitals in the Czech Republic in 2013 revealed that 40% of isolates belonged to ribotype 176. These results suggest that the incidence of CDI (C. difficile infection) in the Czech Republic has increased probably in connection with C. difficile ribotype 176. The molecular systems Xpert C. difficile Epi assay (Cepheid Inc., Sunnyvale, CA) diagnoses toxigenic strains and supports C. difficile ribotype 027 determination based on three specific target places in the toxigenic C. difficile genome. Twenty-nine strains cultivated from stool specimens were evaluated by the Xpert systems as presumed C. difficile PCR ribotype 027 were confirmed as a C. difficile ribotype 176 based on ribotyping. A further 120 C. difficile strains of ribotype 176 were examined for the presence of genes tcdB, cdtB and deletion in position 117 in the tcdC gene. Our experience shows that due to the correspondence of the target places, C. difficile ribotype 176 may be interpreted as ribotype 027 by Xpert C. difficile Epi assay (Cepheid Inc., Sunnyvale, CA). Further molecular analysis as ribotyping based on capillary electrophoresis is needed to differentiate between C. difficile ribotypes 027 and 176 for appropriate epidemiological situation control on local and national levels.
艰难梭菌是当今主要的医院病原体。2013年对捷克共和国11家医院的624株艰难梭菌菌株进行的分析显示，40%的分离株属于核糖体分型176。这些结果表明，捷克共和国艰难梭菌感染（CDI）的发病率可能与艰难梭菌核糖体分型176有关而有所增加。Xpert艰难梭菌Epi检测系统（Cepheid公司，加利福尼亚州森尼韦尔）可诊断产毒菌株，并基于产毒艰难梭菌基因组中的三个特定靶点支持艰难梭菌核糖体分型027的判定。对从粪便标本中培养出的29株菌株进行检测，Xpert系统将其推测为艰难梭菌PCR核糖体分型027，经核糖体分型确认为艰难梭菌核糖体分型176。对另外120株核糖体分型176的艰难梭菌菌株检测tcdB、cdtB基因以及tcdC基因第117位的缺失情况。我们的经验表明，由于靶点位置对应，Xpert艰难梭菌Epi检测系统（Cepheid公司，加利福尼亚州森尼韦尔）可能会将艰难梭菌核糖体分型176解读为核糖体分型027。为在地方和国家层面进行适当的流行病学情况控制，区分艰难梭菌核糖体分型027和176需要进一步进行基于毛细管电泳的核糖体分型分子分析。
