TABLE 2.

Antimicrobial susceptibilities of blaVIM-2-positive clinical isolates and their transconjugants

Antimicrobial agentaP. aeruginosaP. putida
CIb (n = 43)TCb (n = 6)CI (n = 9)TC (n = 2)
MIC rangecMIC50cMIC90cMIC rangeMIC rangeMIC range
Imipenem8->1281612816-3216-12816-32
Meropenem8->128161288-3232-1288-16
Piperacillin64->256256>2568-12864->256256
Piperacillin-tazobactamd32->128128>1288-12832->256128
Cefotaxime>128>128>12864->128>128>128
Cefotaxime-clavulanic acidd>128>128>12832->128>128>128
Ceftazidime32->128128>1288-6432->128128
Aztreonam4-6416322-416-324
Amikacin2->128>12816416->1284
Gentamicin8->128>1281286432->12864
Kanamycin64->128>128>128>12816->128>128
Streptomycin128->128>128>128>128>128128
Tobramycin2->128>1283216-3216->12832
Ciprofloxacin0.12->12832160.12-0.25160.12
  • a MICs of ampicillin, cephalothin, and cefoxitin for all of the strains were >128 μg/ml.

  • b Abbreviations: CI, clinical isolates; TC, transconjugants.

  • c Values are in micrograms per milliliter; MIC50 and MIC90, MICs for 50 and 90% of strains, respectively.

  • d Piperacillin-tazobactam: tazobactam at a fixed concentration of 4 μg/ml; cefotaxime- clavulanic acid: a 2:1 combination.