[E-test susceptibility results of brucella strains for streptomycin, rifampicin, ciprofloxacin and tetracycline].

Although Brucella species are susceptible to many antimicrobial agents in vitro, the susceptibility tests for these bacteria are not well standardized and the break point values are not described yet clearly. The aim of this study was to investigate the minimum inhibitory concentration (MIC) values of 43 Brucella strains isolated from blood cultures by E-test. Streptomycin and rifampicin E-tests were performed for all of the strains, however, tetracycline and ciprofloxacin were tested for only 27 and 17 strains, respectively. The MIC interval for streptomycin was 0.025-1 mg/L, for rifampicin 0.19-1.5 mg/L, for tetracycline <0.016-0.032 mg/L, and for ciprofloxacin 0.094-0.64 mg/L. One strain was found intermediately susceptible to rifampicin. In may be concluded that development of resistance is not eligible against antibiotics which are currently used for brucellosis therapy.