TABLE 1.

Oxacillin resistance determined by mecA gene detection, oxacillin disk diffusion, and the BBL Crystal MRSA ID test

Organism (no. of isolates)	mecA gene	No. of isolates	No. of strains positive by oxacillin disk diffusion after:		No. of isolates with following BBL Crystal MRSA ID test result after incubation for:
			48 h at 30°C	24 h at 37°C	4 h			5 h			6 h
					Sa	Rb	Uc	S	R	U	S	R	U
S. aureus (59)	Present	25	25	25	8	12	5	5	19	1	4	21	0
	Absent	34	34	34	34	0	0	34	0	0	34	0	0
CNS (92)	Present	54	53	53	23	14	17	25	23	6	24	28	2
	Absent	38	39	39	23	0	15	35	0	3	37	0	1

^aS, sensitive to oxacillin. 

^bR, resistant to oxacillin. 

^cU, uninterpretable test reaction.