TABLE 1.

Activities of antimicrobial agents against 195 clinical isolates of carbapenem-nonsusceptible Pseudomonas aeruginosa

Antimicrobial agent	MIC (mg/liter)			Susceptibilitya
	50%	90%	Range
				% S	% I	% R
Ceftolozane/tazobactamb	≥128/4	≥128/4	≤0.5/4 to ≥128/4	37.9	3.1	59.0
Other β-lactam agents
Imipenem	32	≥64	1 to ≥64	3.6	8.7	87.7
Meropenem	32	≥64	≤0.25 to ≥64	13.3	8.2	78.5
Doripenem	32	≥64	≤0.25 to ≥64	16.4	8.7	74.9
Aztreonam	32	≥128	4 to ≥128	13.9	22.0	64.1
Cefepime	≥128	≥128	≤1 to ≥128	17.4	10.8	71.8
Piperacillin/tazobactam	128/4	≥256/4	4 to ≥256/4	13.9	8.7	77.4
Ceftazidime/avibactamb	32/4	≥128/4	1/4 to ≥128/4	41.0		59.0
Other classes
Amikacin	8	≥128	≤1 to ≥128	58.0	6.1	35.9
Gentamicinc				35.4	2.0	62.6
Levofloxacin	32	≥64	≤0.25 to ≥64	18.0	8.7	73.3
Polymyxin B	1	2	≤0.25 to ≥32		96.9	3.1

^aS, susceptible; I, intermediate; R, resistant.

^bSusceptibility was determined using gradient MIC test strips.

^cSusceptibility was determined using disk diffusion or Vitek routinely at the microbiology laboratory.