Comparative in-vitro activity of trovafloxacin and other related drugs against isolates of streptococcus oralis.
OBJECTIVE
The in-vitro activity of trovafloxacin a new quinolone was compared with that of ciprofloxacin, erythromycin, various b-lactam and other appropriate antibiotics such as vancomycin, teicoplanin and clindamycin against 60 isolates of S. oralis.


METHODS
Minimal inhibitory concentration was performed using the agar dilution technique and micro-titer method. In addition minimal bactericidal concentration and time-kill studies were carried out to estimate the bactericidal activity of trovafloxacin against S. oralis isolates.


RESULTS
Trovafloxacin showed a four-fold increase in activity over ciprofloxacin, with a narrow minimal inhibitory concentration range, MIC50 and mode values of 0.25 mg/l. Although the minimal inhibitory concentrations of trovafloxacin for S.oralis were relatively high compared to all the antibiotics tested. The in-vitro bactericidal activity of Trovafloxacin was greater than all other antibiotics against S. oralis. Five out of 10 isolates showed there was a 100% kill within 6 hours of contact; in all other cases, the kill time was between 6 and 24 hours.


CONCLUSIONS
Overall, trovafloxacin showed superior minimal inhibitory concentration, bactericidal concentration and kill time when compared with different antibiotics.
Rafay
A M
AM
Department of Microbiology and Immunology, Sultan Qaboos University Hospital, Muscat, Sultanate of Oman. Akbar@gto.net.com
D000890:Anti-Infective Agents / Q000494:pharmacology*; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000494:pharmacology*; D019533:Streptococcus oralis / Q000187:drug effects*
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009287:Naphthyridines; C080163:trovafloxacin