Fig. 2

Time–kill studies for colistin (COL), meropenem (MEM) and vancomycin (VAN), alone and in combination, against MDR A. baumannii. a The bactericidal activity of COL + VAN is represented. Values in bracket represent the actual concentration (mg/L). b The bactericidal activity of COL + MEM is represented. Values in bracket represent the actual concentration (mg/L). c The bactericidal activity of COL + MEM + VAN is represented. The actual concentrations of the triple combinations are: 0.5 × MIC COL (0.5 mg/L) COL + 0.25 × MIC VAN (32 mg/L) + 0.5 × MIC MEM (64 mg/L) and 0.5 × MIC COL (0.5 mg/L) COL + 0.125 × MIC VAN (16 mg/L) + 0.5 × MIC MEM (64 mg/L). The dashed horizontal line represents a reduction of 3 log10 cfu/mL compared with the initial bacterial count. GC, growth control