TABLE 2.

Evaluation of accuracies of three automated systems for susceptibility testing of 100 P. aeruginosa strains against β-lactam antimicrobial agents

Antimicrobial and category	% of isolates
	Consensusa	MicroScan WalkAway	VITEK 2	VITEK
Aztreonam
Susceptible	47	41	33	49
Intermediate	26	32	41	14
Resistant	27	27	26	37
Cefepime
Susceptible	59	39	57b	44
Intermediate	27	29	22	35
Resistant	14	32	21	21
Ceftazidime
Susceptible	44	43	44	42
Intermediate	13	16	12	20
Resistant	43	41	44	38
Imipenem
Susceptible	71	68	72b	69
Intermediate	10	9	14	1
Resistant	19	23	14	30
Piperacillin-tazobactam
Susceptible	50	68	78b	71
Resistant	50	32	22	29

^aConsensus result among the broth microdilution (frozen dry-form panels), agar dilution, and disk diffusion methods.

^bThe system did not provide results for one strain.