MIC (µg/ml)

10 mM EDTA

C

C+S

A+C

P+Z

M

Cef+S

Efflux positive* (n=15)

Without EDTA

>512

256-512

>512

256-512

256-512

256-512

With EDTA

256

8-16

256

128-256

32-64

128-256

E.coli MTCC 739 (efflux negative)

Without EDTA

2

0.5

4

2

0.5

4

With EDTA

2

0.5

4

2

0.5

4
C: Ceftriaxone; C+S: Ceftriaxone+sulbactam; P+Z: Piperacillin+tazobactam; A+C: Amoxicillin+clavulanic acid; cef+S: Cefoparazone+Sulbactam; M: Meropenem.
*Efflux positive represents the presence of AcrAB-TolC overexpressing clinical isolates.
Table 2: Minimum inhibitory concentrations (MICs) of drugs on planktonic cultures of AcrAB-tolC positive clinical isolates and E. coli MTCC 739.