TABLE 4.

MICs of MSI-78 for 61 anaerobic bacteria and rates of susceptibility to MSI-78 and six other antibiotics

Microorganism	No.	MSI-78 MIC (μg/ml)		% of isolates for which MSI-78 MICs were ≤64 μg/ml	% of isolates susceptible toa:
		Geometric mean	Range		OFLX	CFOX	CLIN	MET	PEN	PIP
Bacteroides fragilis	6	5.6	4–8	100	67	100	83	100	0	67
Bacteroides ovatus	7	5.9	4–8	100	0	29	43	100	0	29
Bacteroides ureolyticus	3	0.4	0.25–0.5	100	33	100	100	100	100	100
Bacteroides vulgatus	6	4.0	4–4	100	83	33	83	100	0	17
Clostridium difficile	4	1.7	0.5–4	100	25	0	100	100	100	100
Clostridium perfringens	5	18.4	8–32	100	100	100	100	100	100	100
Clostridium ramosum	2	16	16–16	100	0	100	0	100	100	100
Clostridium sporogenes	2	6	8–32	100	100	100	0	100	100	100
Clostridium sp.	1	32		100	100	100	0	100	100	100
Peptostreptococcus anaerobius	6	45	32–64	100	100	100	100	100	33	100
Peptostreptococcus asaccharolyticus	3	5	4–8	100	0	100	100	100	67	100
Peptostreptococcus magnus	4	0.7	0.5–1	100	0	100	75	100	100	100
Prevotella bivia	9	69	32–128	78	100	100	100	100	22	100
Prevotella melaninogenica	3	51	32–64	100	33	100	100	100	33	100

^aAbbreviations (susceptibility breakpoints are in parentheses): OFLX, ofloxacin (≤2.0 μg/ml); CFOX, cefoxitin (≤16 μg/ml); CLIN, clindamycin (≤2.0 μg/ml); MET, metronidazole (≤8.0 μg/ml); PEN, penicillin G (≤0.5 μg/ml); PIP, piperacillin (≤32 μg/ml).