TABLE 1.

Distribution of cefoxitin and moxalactam inhibition zone diameters by disk diffusion testing of 213 isolates of S. aureus by resistance genotype (mecA PCR results)

Cefoxitin disk												Moxalactam 30-μg disk (Oxoid)
10 μg (Rosco)			30 μg (Rosco)			60 μg (Rosco)			30 μg (Oxoid)
Inhibition zone diam (mm)	No. of results mecA positive	No. of results mecA negative	Inhibition zone diam (mm)	No. of results mecA positive	No. of results mecA negative	Inhibition zone diam (mm)	No. of results mecA positive	No. of results mecA negative	Inhibition zone diam (mm)	No. of results mecA positive	No. of results mecA negative	Inhibition zone diam (mm)	No. of results mecA positive	No. of results mecA negative
≤11	151		≤14	148		≤19	124		≤15	146		≤13	102
12	2		15	2		20	9		16	5		14	18
13			16	2		21	14		17	3		15	12
14	2		17	1		22	7		18			16	15
15			18	2		23			19	1		17	2
16a	1		19	1		24	1		20			18	2
17		4	20			25			21			19	2
18	1b	3	21			26			22	1b		20	1
19		6	22			27			23			21	1
20		8	23		1	28	1b		24			22
21		15	24		1	29			25		1	23
≥22		20	≥25	1b	54	≥30	1b	56	≥26	1b	55	≥24	2b	56

^aSusceptible and resistant breakpoints fall between the boldface diameters.

^bCryptic MRSA strain (MIC = 0.5 mg/liter).