Treatment of Anaerobic Infections with Lincomycin and Clindamycin

The efficacy of lincomycin and clindamycin against anaerobic bacteria was evaluated by in vitro sensitivity studies and clinical observations. Ninety-six per cent of 219 stock strains of various anaerobes were sensitive to 3.1 μg per milliliter of clindamycin, including 96 per cent of 123 strains of Bacteroides fragilis. All but two strains (both Fusobacterium varium) were inhibited by 6.2 μg per milliliter, a clinically achievable level. Most species tested were also sensitive, although less so, to lincomycin. Resistant organisms included most B. fragilis and many Clostridium perfringens strains. The patients treated had infections due to a variety of anaerobes, including B. fragilis. Response was favorable in 10 of 11 patients who were treated with lincomycin and in each of 14 patients treated with clindamycin. The data suggest that these agents, particularly clindamycin, are useful in the therapy of anaerobic infections.