In vitro activity of levofloxacin against a selected group of anaerobic bacteria isolated from skin and soft tissue infections.

The in vitro activity of levofloxacin was compared to the activities of ofloxacin, ciprofloxacin, ampicillin-sulbactam (2:1), cefoxitin, and metronidazole for a selected group of anaerobes (n = 175) isolated from skin and soft tissue infections by using the National Committee for Clinical Laboratory Standards-approved Wadsworth method. Ampicillin-sulbactam and cefoxitin inhibited 99% of the strains of this select group, levofloxacin and ofloxacin inhibited 73 and 50%, respectively, at 2 microg/ml, and ciprofloxacin inhibited 51% at 1 microg/ml. The geometric mean MIC of levofloxacin was lower than those of ofloxacin and ciprofloxacin for every group except Veillonella.