TABLE 2.

MIC50 and MIC90 values and percent antimicrobial resistance for 284 samples of P. aeruginosa

Antimicrobial agentBreakpoint for resistance (μg/ml)MDR isolatesa (n = 214)Non-MDR isolates (n = 70)
% ResistantRange (μg/ml)MIC50 (μg/ml)MIC90 (μg/ml)% ResistantRange (μg/ml)MIC50 (μg/ml)MIC90 (μg/ml)
PIP≥128100128->512>512>51241.41->51264512
TZP≥128/4100128->512512>51221.40.5-25632128
CAZ≥3210032->512>512>51225.71->512864
IPM≥1610032->51225651247.10.25->512832
DRPM≥1699.12->512>512>51234.3<0.125->512832
MEM≥1610032->512512>51244.3<0.125->512432
AZT≥3299.516->51212812852.90.5-1283264
ABK≥491.62-164824.3<0.125-1618
AMK≥3210032-2561282562.90.25-256216
GEN≥1657.50.25->32161612.9<0.125->128116
STR≥4100512->512>512>51298.62->51232128
CIP≥410016->12864>12851.4<0.125->128464
OFX≥810032->128>128>12862.9<0.125->12816>128
PL-B≥428.02-82422.91-824
  • a Isolates defined as resistant to three antibiotics, imipenem (MIC ≥ 16 μg/ml), amikacin (MIC ≥ 32 μg/ml), and ciprofloxacin (MIC ≥ 4 μg/ml).