TABLE 1.

Distribution of antimicrobials tested against 110 toxigenic clinical C. difficile isolates

Antimicrobial agent	No. of strains for which the antimicrobial agent MIC (μg/ml) was:
	≤0.0019	0.0039	0.0078	0.015	0.03	0.06	0.125	0.25	0.5	1	2	4	8	16	32	64a
Rifalazil	14	20	45	27	1											3*
Rifaximin	12	1	73	20	1											3*
OPT-80				9	11	29	50	11
Tizoxanide				1	7	83	18		1
Nitazoxanide					4	71	33		2
Metronidazole					2	3	70	32	3
Tinidazole					1	2	66	35	5	1
Ramoplanin						1	19	45	45
Tigecycline						2	89	17	1	1
Vancomycin						2			34	68	5	1
Doripenem										78	31	1
Meropenem										16	89	5
Gatifloxacin									3	73	17		1	9	6	1†
Moxifloxacin										57	38		1	8	6
Levofloxacin											9	82	1		5	13‡

^a*, Three strains had MICs of >256 μg/ml for rifalazil and rifaximin; †, one strain had an MIC of >32 μg/ml for gatifloxacin; ‡, thirteen strains had an MIC of >32 μg/ml for levofloxacin.