Antimicrobial activity of gatifloxacin compared to seven other compounds tested against gram-positive organisms isolated at 10 cancer-treatment centers

Gram-positive bacterial pathogens are important causes of disease in cancer patients and are becoming increasingly resistant to available antimicrobia l agents. We examined the in vitro activity of gatifloxacin, a new, fluoroq uinolone, compared with other quinolones, ceftazidime, and traditional Gram -positive-active agents tested against pathogens isolated from patients at 10 cancer treatment hospitals in the United States. A total of 1,128 Gram-p ositive isolates were tested by the E-test method (AB BIODISK, Solna Sweden ) with results validated by concurrent quality control strain analysis. Gat ifloxacin was more potent than either citrofloxacin or levofloxacin against all Gram-positive species. Vancomycin was the most active agent tested aga inst all species except Bacillus spp., which were more susceptible to the f luoroquinolones. When tested against these Gram-positive pathogens from pat ients with cancer, the spectrum of gatifloxacin was also greater than that of levofloxacin and ciprofloxacin. Gatifloxacin may have a role as paid of prophylactic or therapeutic antimicrobial regimens for selected cancer pati ents with Gram-positive infections. (C) 1999 Elsevier Science Inc.