Novel Microdilution Method to Assess Double and Triple Antibiotic Combination Therapy In Vitro

Figure 2

Evaluation of double and triple combinations of ciprofloxacin, amikacin, and ceftazidime against isolate PA14 by time-kill assay in vitro. Isolate PA14 was used to inoculate 100 mL of cations-adjusted Muller Hinton broth in 250 mL Erlenmeyer flasks to give initial inoculum size of 1 to 5 × 10⁵ CFU/mL. The antibiotics were added alone in double or triple combinations at concentrations equivalent to 1/2 of their MICs. AMK, amikacin; CIP, ciprofloxacin; CAZ, ceftazidime.