Table 1.

MIC range, MIC₅₀, and MIC₉₀ for antimicrobial agents tested against 316 C. difficile isolates

Drug	MIC (μg/ml)			No. resistant	% resistant
	Range	50%	90%
Clindamycin	0.25–>256	4	>256	131	41.50
Metronidazole	0.125–4	0.25	0.5	0	0
Rifampin	≤0.002–>32	≤0.002	≤0.002	25	7.90
Moxifloxacin	0.5–>32	2	>32	120	38.00