Antibacterial activity of trovafloxacin against nosocomial Gram- positive and Gram-negative isolates

Abstract

A total of 1132 clinical isolates from 952 patients with nosocomial infections were tested against the fluoroquinolone trovafloxacin by the agar dilution method. They comprised 285 staphylococci, 111 streptococci, 94 enterococci and 470 isolates of Enterobacteriaceae, 92 Pseudomonas aeruginosa, 27 Stenotrophomonas maltophilia, 28 Haemophilus influenzae and 25 Acinetobacter calcoaceticus. The in-vitro activity of trovafloxacin was compared with that of ciprofloxacin, norfloxacin, beta-lactam and aminoglycoside agents. Over 96% of Enterobacteriaceae were susceptible to trovafloxacin with an MIC of <0.03-4 mg/L. It also inhibited 97% and 100% clinical isolates of P. aeruginosa and S. maltophilia, respectively. All staphylococci, including 51 strains of methicillin-resistant Staphylococcus aureus, were susceptible to trovafloxacin, which also had excellent activity against streptococci and enterococci, inhibiting all 111 strains of the former and 94% of the latter. Trovafloxacin had a greater activity against both Gram-positive and Gram-negative bacteria than ciprofloxacin, norfloxacin, penicillins, cephalosporins and the aminoglycosides tested.

Activities of Trovafloxacin and Ampicillin-Sulbactam Alone or in Combination versus Three Strains of Vancomycin- Intermediate Staphylococcus aureus in an In Vitro Pharmacodynamic Infection Model

“…This glycopeptide resistance results in decreased susceptibility to other glycopeptide antimicrobial agents, such as teicoplanin and LY333328 (1, 3, 27, 29, 30; J. R. Aeschlimann, E. Hershberger, and M. J. Rybak, submitted for publication), so alternate classes of antimicrobial agents will be necessary to treat VISA infections. Trovafloxacin is a fluoroquinolone antimicrobial agent which has greatly improved activity against gram-positive pathogens (11,28) and might have adequate activity against a VISA isolate. As a threefold increase in the expression of PBPs 2 and 2Ј has been reported for Mu50 (17) as well as for in vitro vancomycin-resistant staphylococcal mutants (21), we hypothesized that the administration of higher doses of ampicillinsulbactam might also provide adequate anti-VISA activity, since ampicillin has a good affinity for these PBPs (2).…”

Effects of ciprofloxacin on salt marsh sediment microbial communities

“…We also expected selective effects of the antibiotic; in clinical trials ciprofloxacin showed higher bactericidal activity against GN than GP bacteria (Cunha et al, 1997;Dalhoff and Schmitz, 2003;Berlanga et al, 2004). In contrast, both biomass and PLFA numbers increased in ciproflox- Averages are provided with s.e.…”

Enumeration and characterization of bacteria in mineral water by improved direct viable count method

“…At least two of the four fluoroquinolones tested were able to achieve growth inhibition of the different isolates at concentrations within the range of the first-generation quinolone concentrations used in the antibiotics cocktail described by Kogure et al (1984). However, more potent, new fluoroquinolones, which have been reported to be highly active against the genus Pseudomonas and allied taxa (Ford et al 1993;Cunha et al 1997), should be tested in order to ensure growth inhibition at lower antibiotic concentrations.…”

“…In both experiments, the method appeared to be effective and efficient under the defined conditions. Some new fluoroquinolones, which appear to be very active on many types of micro-organisms (Ford et al 1993;Cunha et al 1997), might also be useful.…”