ANTIBACTERIAL ACTIVITY OF TROVAFLOXACIN AGAINST GRAM-POSITIVE BLOOD CULTURE ISOLATES FROM NOSOCOMIAL INFECTIONS

The history of quinolone agents as chemotherapeutic agents began in 19 62 with the accidental discovery of nalidixic acid. The use of this ag ent in clinical practice, however, was restricted primarily to the ora l treatment of urinary tract infections. Its antibacterial spectrum wa s limited, and its use was associated with rapid emergence of resistan ce. The newer fluoroquinolones represent a major advance in antimicrob ial chemotherapy and have evolved from chemical modifications of nalid ixic acid (1). The first breakthrough in the development of newer fluo roquinolones occurred during the early 1980s, when norfloxacin was syn thesized. The enhanced activity of this drug as an orally active agent for urinary tract infections resulted in the development of additiona l fluoroquinolones such as ciprofloxacin, enoxacin, ofloxacin, and oth ers. These compounds are very active against enteric and other gram-ne gative bacteria, but their activity against gram-positive organisms, e specially against streptococci, is limited. This led to the search for , and the development of, a wide array of chemical analogues in which the nucleus of 4-quinolone was manipulated in order to improve the spe ctrum of activity. Trovafloxacin (CP-99,219) is one such drug. We desc ribe here the comparative in vitro activity of this fluoroquinolone ag ainst gram-positive bacteria isolated from the blood of patients with nosocomial infections.