title: Susceptibility of anaerobic bacteria to metronidazole: relative resistance of non-spore-forming gram-positive baccilli.
abstract: Susceptibility of 358 clinical isolates of obligate anaerobes to metronidazole was determined by an agar-dilution technique. Only 66% of all isolates were inhibited by 6.25 mug/ml, whereas 30% required larger than or equal to 50 mug/ml. Considerable variation in susceptibility was observed among different genera and species of bacteria. Fusobacterium was most senstitive, followed by Clostridium, Bacteroides and Peptococcus, Peptostreptococcus, Veillonella and Acidaminococcus, and non-spore-forming gram-positive bacilli. Bacteroides fragilis was more sensitive than other species of Bacteroides. Similarly, Clostridium perfringens was more susceptible than other species of Clostriduim. While metronidazole appears to be a promising antimicrobial agent for infections caused by Fusobacterium, Clostrididium, and B.fragilis, therapy for infections with other anaerobic bacteria should be guided by in vitro tests of sensitiivity.
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D000818:Animals; D001419:Bacteria / Q000187:drug effects*; D001424:Bacterial Infections / Q000188:drug therapy; D001439:Bacteroides / Q000187:drug effects; D003013:Clostridium / Q000187:drug effects; D003016:Clostridium perfringens / Q000187:drug effects; D004352:Drug Resistance, Microbial; D005673:Fusobacterium / Q000187:drug effects; D008795:Metronidazole / Q000494:pharmacology* / Q000627:therapeutic use; D008826:Microbial Sensitivity Tests / Q000379:methods; D010460:Peptococcus / Q000187:drug effects; D010462:Peptostreptococcus / Q000187:drug effects; D012756:Sheep; D014678:Veillonella / Q000187:drug effects
chemical_list: D008795:Metronidazole