We are just woriking on it with standart A. baumannii strains. We added different concentrations of Et Br (100, 50, 25, 12.5 ug/mL) in to tryptic soy agar as mentioned in the study of JM Pages et al. It seems that best results were obtained with 25 ug/mL of Et Br in tryptic soy agar with A. baumannii. We try to optimize our results... 

I found this a difficult assay to quantify. Ensure that you have a good set of control strains so that you know if it is working. Try to get hold of  a strain that overexpresses efflux pumps and one that does not.

Dear Ibrahim

You can use the method was described by Martins, M. ;Viveiros, M. ;Couto, I. ;Costa, S.S. ;Pacheco, T. ;Fanning, S.; Pagès, J.M. and Amaral, L.2011. Identification of efflux pump-mediated multidrug-resistant bacteria by the Ethidium Bromide-agar Cartwheel Method In Vivo. 25:171–178.

and You can use this method with Klebsiella

Best regrades

Thanks for aswers. i want to ask you that how you decide optimal concentration? best result for your reference strain at optimal concentraiton?

 I used the following assay and worked very well, try it.

A 96-well plate fluorescence assay for assessment of cellular permeability and active efflux in Salmonella enterica serovar Typhimurium and Escherichia coli

J Antimicrob Chemother, 2010, 65(8), 1655-63