Efficacy of trovafloxacin in an in vitro pharmacodynamic simulation of an intraabdominal infection.
An in vitro model simulating trovafloxacin concentrations in human serum after standard doses was used to investigate the activity of this drug with time against Bacteroides fragilis, Escherichia coli, Enterococcus faecalis and Staphylococcus aureus. Antibiotic concentrations used for each incubation period were: 4.24 mg/l (0-1 h), 3.69 mg/l (1-3 h), 3.25 mg/l (3-6 h), 2.38 mg/l (6-8 h), 1.35 mg/l (8-24 h). A 99.9% initial inoculum reduction (> 3 log10 cfu/ml) was defined as bactericidal activity. Bactericidal activity against these organisms was obtained with trovafloxacin after the first hour of incubation, and similar activity was obtained against B. fragilis, E. faecalis and S. aureus after 3 h, when they were tested individually. When the strains were tested as mixed culture, there was bactericidal activity against E. coli after 1 h incubation and after 3 h for S. aureus. This activity was observed against B. fragilis and E. faecalis after 6 h incubation in the mixed culture assays and after 3 h when organisms were tested individually. Regrowth was not observed over a 24 h period. These data show that trovafloxacin might be effective in intraabdominal infections caused by mixed aerobic and anaerobic microorganisms.
Alou
L
L
Microbiology Department, School of Medicine, Universidad Complutense de Madrid, Spain.
Anta
M L
ML
Del Potro
M G
MG
Fuentes
F
F
Balcabao
I P
IP
Gomez-Lus
M L
ML
Prieto
J
J
D018784:Abdominal Abscess / Q000097:blood* / Q000188:drug therapy / Q000382:microbiology; D000890:Anti-Infective Agents / Q000097:blood / Q000493:pharmacokinetics*; D001441:Bacteroides fragilis / Q000187:drug effects; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D009287:Naphthyridines / Q000097:blood / Q000493:pharmacokinetics*; D013211:Staphylococcus aureus / Q000187:drug effects; D013997:Time Factors
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009287:Naphthyridines; C080163:trovafloxacin