Bidet P, Lalande V, Salauze B, Burghoffer B, Avesani V, Delmée M, Rossier A, Barbut F, Petit J C
Laboratoire de Bactériologie, Hôpital Saint-Antoine, Centre Hospitalo-Universitaire Saint-Antoine, Université Paris 6, Assistance Publique-Hôpitaux de Paris, Paris, France.
J Clin Microbiol. 2000 Jul;38(7):2484-7. doi: 10.1128/JCM.38.7.2484-2487.2000.
Clostridium difficile is now recognized as the major agent responsible for nosocomial diarrhea in adults. Among the genotyping methods available, arbitrarily primed PCR (AP-PCR), PCR-ribotyping, and pulsed-field gel electrophoresis (PFGE) have been widely used for investigating outbreaks of C. difficile infections. However, the comparative typing ability, reproducibility, discriminatory power, and efficiency of these methods have not been fully investigated. We compared the results of three methods-AP-PCR with three different primers (AP3, AP4, and AP5), PCR-ribotyping, and PFGE (with SmaI endonuclease)-to differentiate 99 strains of C. difficile that had been previously serogrouped. Typing abilities were 100% for PCR-ribotyping and AP-PCR with AP3 and 90% for PFGE, due to early DNA degradation in strains from serogroup G. Reproducibilities were 100% for PCR-ribotyping and PFGE but only 88% for AP-PCR with AP3, 67% for AP-PCR with AP4, and 33% for AP-PCR with AP5. Discriminatory power for unrelated strains was >0.95 for all the methods but was lower for PCR-ribotyping among serogroups D and C. PCR-based methods were easier and quicker to perform, but their fingerprints were more difficult to interpret than those of PFGE. We conclude that PCR-ribotyping offers the best combination of advantages as an initial typing tool for C. difficile.
艰难梭菌现已被公认为是导致成人医院内腹泻的主要病原体。在现有的基因分型方法中，任意引物聚合酶链反应（AP-PCR）、聚合酶链反应核糖体分型（PCR-ribotyping）和脉冲场凝胶电泳（PFGE）已被广泛用于调查艰难梭菌感染的暴发情况。然而，这些方法的比较分型能力、可重复性、鉴别力和效率尚未得到充分研究。我们比较了三种方法的结果——使用三种不同引物（AP3、AP4和AP5）的AP-PCR、PCR-核糖体分型和PFGE（使用SmaI内切酶），以区分99株先前已进行血清分型的艰难梭菌菌株。PCR-核糖体分型以及使用AP3的AP-PCR的分型能力为100%，PFGE的分型能力为90%，这是由于G血清型菌株中存在早期DNA降解。PCR-核糖体分型和PFGE的可重复性为100%，但使用AP3的AP-PCR的可重复性仅为88%，使用AP4的AP-PCR为67%，使用AP5的AP-PCR为33%。所有方法对不相关菌株的鉴别力均>0.95，但在D和C血清型中，PCR-核糖体分型的鉴别力较低。基于PCR的方法操作更简便、快捷，但其指纹图谱比PFGE的更难解读。我们得出结论，作为艰难梭菌的初始分型工具，PCR-核糖体分型具有最佳的综合优势。
