Killing activities of trovafloxacin alone and in combination with beta-lactam agents, rifampin, or vancomycin against Streptococcus pneumoniae isolates with various susceptibilities to extended-spectrum cephalosporins at concentrations clinically achievable in cerebrospinal fluid.
The killing activities of trovafloxacin alone and in combination with beta-lactam agents (extended-spectrum cephalosporins, meropenem), rifampin, or vancomycin were evaluated against 20 genotypically characterized Streptococcus pneumoniae isolates for which amoxicillin MICs were >/=4 microg/ml (cefotaxime MICs, >/=4 microg/ml for six strains) at concentrations clinically achievable in cerebrospinal fluid. At 6 h the mean killing activity of trovafloxacin alone (range, 2.6 to 2.9 log(10) CFU/ml) did not vary significantly according to the susceptibility of the strains to beta-lactam agents. The activities of trovafloxacin or vancomycin added to the beta-lactam agents and the combination trovafloxacin-vancomycin were additive or indifferent. Against the ceftriaxone-resistant isolates, the killing activity of the combination of a beta-lactam agent and trovafloxacin did not differ significantly from that of a beta-lactam agent and vancomycin.
Fitoussi
F
F
Service de Microbiologie, Hôpital Robert Debré, 75019 Paris, France.
Doit
C
C
Geslin
P
P
Bingen
E
E
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000494:pharmacology*; D000904:Antibiotics, Antitubercular / Q000494:pharmacology; D018550:Cephalosporin Resistance / Q000502:physiology*; D002511:Cephalosporins / Q000494:pharmacology; D004347:Drug Interactions; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000494:pharmacology*; D012293:Rifampin / Q000494:pharmacology; D013296:Streptococcus pneumoniae / Q000187:drug effects*; D014640:Vancomycin / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D000904:Antibiotics, Antitubercular; D002511:Cephalosporins; D024841:Fluoroquinolones; D009287:Naphthyridines; D014640:Vancomycin; C080163:trovafloxacin; D012293:Rifampin