Clostridium perfringens type A. Comparison of in vitro and in vivo activity of twelve antimicrobial drugs.

Penicillin G and imipenem (N-formimidoyl thienamycin) in vitro were the most active of twelve examined antimicrobial drugs against clinical and fecal isolates of Clostridium perfringens type A. However, vancomycin and fosfomycin, which revealed suboptimal in vitro bactericidal activity, proved as efficacious as penicillin G and imipenem in an experimental mode of murine gas gangrene. Thus, conventional in vitro tests were not uniformly predictive for in vivo (murine) chemotherapeutic efficacy.