Effect of toxins produced by various Clostridium difficile strains on cecum size reduction in gnotobiotic mice.

Inoculation of axenic mice with Clostridium difficile strains induced a significant reduction in ceca weight (dry or wet), whereas a nontoxinogenic strain led to a partial reduction. A strain, which produces cytotoxin and no enterotoxin in vivo, caused a reduction similar to that observed with a nontoxinogenic strain. Simultaneous cytotoxin and enterotoxin production by various C. difficile strains caused the cecum size to diminish to that observed for conventional control mice.