Antibacterial activity of lomefloxacin against Brucella melitensis.

The in vitro activity of lomefloxacin was tested against 114 clinical isolates of Brucella melitensis. Comparison was made with ciprofloxacin, tetracycline, gentamicin, rifampin, and trimethoprim-sulfamethoxazole. Lomefloxacin inhibited 113 (99.1%) of the 114 strains tested at less than or equal to 0.5 microgram/ml. It was comparable to ciprofloxacin, tetracycline and gentamicin in antimicrobial potency. One strain that was previously susceptible to ciprofloxacin and had become resistant after the patient was treated with ciprofloxacin showed cross-resistance to lomefloxacin.