B acillus amyloliquefaciens as prophylactic treatment for C lostridium difficile ‐associated disease in a mouse model

Background and Aim  Probiotics might offer an attractive alternative for standard antibiotic therapy to treat C lostridium difficile infections ( CDI ). We specifically selected a B acillus amyloliquefaciens strain for its high in vitro antibacterial activity against C . difficile and tested its efficacy to prevent CDI in a mouse model. Methods B . amyloliquefaciens supernatant was tested against a large collection of C . difficile strains using an agar well diffusion test. B . amyloliquefaciens was orally administered to C57BL /6 mice in which CDI was induced using C . difficile   VPI 10463, and its effect was compared with control mice receiving no treatment and mice receiving S accharomyces boulardii . Mice were followed up daily for signs of disease including weight loss. At necropsy, the colon was collected and subjected to histopathological analysis. C . difficile toxin A / B levels and colon weight/length and colon/body weight ratios were calculated. Results   B . amyloliquefaciens supernatant was able to inhibit the growth of all C . difficile strains. Results of the in vivo trial indicated a significant weight loss for untreated and S . boulardii ‐treated mice as compared to B . amyloliquefaciens ‐treated mice. C . difficile toxin A and B levels were significantly higher for untreated and S . boulardii ‐treated mice than B . amyloliquefaciens ‐treated mice. A significantly lower degree of colon damage was detected for B . amyloliquefaciens ‐treated mice as compared to untreated and S . boulardii ‐treated mice, based on histopathological analysis, colon weight/length and colon/body weight ratios. Conclusion  Administration of B . amyloliquefaciens was successful in preventing CDI in a mouse model.