Hines VA Hospital, Hines, Illinois, USA.
Antimicrob Agents Chemother. 2013 Nov;57(11):5266-70. doi: 10.1128/AAC.00580-13. Epub 2013 Aug 12.
Nontoxigenic Clostridium difficile (NTCD) has been shown to prevent fatal C. difficile infection in the hamster model when hamsters are challenged with standard toxigenic C. difficile strains. The purpose of this study was to determine if NTCD can prevent C. difficile infection in the hamster model when hamsters are challenged with restriction endonuclease analysis group BI C. difficile strains. Groups of 10 hamsters were given oral clindamycin, followed on day 2 by 10(6) CFU of spores of NTCD strain M3 or T7, and were challenged on day 5 with 100 CFU of spores of BI1 or BI6. To conserve animals, results for control hamsters challenged with BI1 or BI6 from the present study and controls from previous identical experiments were combined for statistical comparisons. NTCD strains M3 and T7 achieved 100% colonization and were 100% protective against challenge with BI1 (P ≤ 0.001). M3 colonized 9/10 hamsters and protected against BI6 challenge in the colonized hamsters (P = 0.0003). T7 colonized 10/10 hamsters, but following BI6 challenge, cocolonization occurred in 5 hamsters, 4 of which died, for protection of 6/10 animals (P = 0.02). NTCD colonization provides protection against challenge with toxigenic BI group strains. M3 is more effective than T7 in preventing C. difficile infection caused by the BI6 epidemic strain. Prevention of C. difficile infection caused by the epidemic BI6 strain may be more challenging than that of infections caused by historic BI1 and non-BI C. difficile strains.
无细胞毒素艰难梭菌（NTCD）已被证明可在仓鼠模型中预防由标准细胞毒素艰难梭菌菌株引起的致命性艰难梭菌感染。本研究的目的是确定当仓鼠受到 BI 型艰难梭菌菌株的挑战时，NTCD 是否可以预防仓鼠模型中的艰难梭菌感染。10 只仓鼠一组，给予口服克林霉素，然后在第 2 天给予 NTCD 株 M3 或 T7 的 10（6）CFU 孢子，并在第 5 天用 100 CFU BI1 或 BI6 的孢子进行挑战。为了节省动物，将来自本研究和先前相同实验对照的对照仓鼠用 BI1 或 BI6 进行挑战的结果进行了组合，以便进行统计比较。NTCD 株 M3 和 T7 实现了 100%定植，对 BI1 的挑战有 100%的保护作用（P≤0.001）。M3 定植了 9/10 只仓鼠，并保护了定植的仓鼠免受 BI6 挑战的影响（P=0.0003）。T7 定植了 10/10 只仓鼠，但在 BI6 挑战后，5 只仓鼠发生共定植，其中 4 只死亡，对 6/10 只动物有保护作用（P=0.02）。NTCD 定植可提供针对细胞毒素 BI 组菌株的挑战的保护。M3 在预防 BI6 流行株引起的艰难梭菌感染方面比 T7 更有效。预防由流行 BI6 株引起的艰难梭菌感染可能比由历史 BI1 和非 BI 型艰难梭菌株引起的感染更具挑战性。
