TABLE 2.

Comparative in vitro activities of different antibiotic compounds against MRSA in relation to ciprofloxacin susceptibility

Test agent	MIC (μg/ml)
	Ciprofloxacin-susceptible MRSA (n = 62)			Ciprofloxacin-resistant MRSA (n = 189)
	Range	MIC50	MIC90	Range	MIC50	MIC90
Ciprofloxacin	0.12–2	0.25	1.0	4–>256	32	64
Clinafloxacin	≤0.06–0.12	≤0.06	≤0.06	≤0.06–4	0.5	1
Grepafloxacin	≤0.06–0.12	≤0.06	≤0.06	≤0.06–64	16	32
Levofloxacin	≤0.06–0.5	0.12	0.25	1–64	4	16
Moxifloxacin	≤0.06–0.12	≤0.06	≤0.06	≤0.06–4	2	2
Ofloxacin	0.12–1	0.25	0.5	1–64	16	32
Sparfloxacin	≤0.06–1	≤0.06	0.12	≤0.06–64	4	16
Trovafloxacin	≤0.06–0.5	≤0.06	≤0.06	≤0.06–8	1	4
Gentamicin	0.12–>256	64	256	≤0.06–>256	64	256
Linezolid	0.5–2	1	2	0.12–2	1	2
Quinupristin-dalfopristin	≤0.06–4	0.5	1	≤0.06–4	0.5	1
Vancomycin	0.12–2	1	1	0.5–2	1	2