In vitro activity of tigecycline, tetracycline and fluoroquinolones against Brucella melitensis.

Brucellosis is a major zoonotic disease of global importance. Forty years after active drug therapy was defined, there is no optimum antibiotic therapy for brucellosis due to relatively high rates of relapse and treatment failure. The aim of this study was to assess the in vitro susceptibility of 60 Brucella melitensis isolates obtained from blood and fluids to tigecycline, tetracycline and three quinolones (ciprofloxacin, levofloxacin, moxifloxacin). The minimum inhibitory concentrations (MICs) of these antibiotics were determined by E-test method. According to the MIC90, levofloxacin (MIC90 0.094 microg/mL) was found to be the most active agent, followed by tigecycline (MIC90 0.125 microg/mL), moxifloxacin (MIC90 0.125 microg/mL), ciprofloxacin (MIC 90 0.19 microg/mL) and tetracycline (MIC90 0.25 microg/mL). The results suggest that tigecycline can be a therapeutic alternative option for the treatment of brucellosis.