In vitro and in vivo antibacterial activities of telithromycin.
BACKGROUND
Telithromycin is one of the ketolides, characterised by a 3-keto group instead of L-cladinose and a C(11)-C(12) carbamate link by an alkyl chain to a pyridinum and imidazolium ring side chain. We evaluated in vitro and in vivo antibacterial activities of telithromycin against gynaecological pathogens.


METHODS
In the vitro study, the antibacterial activity of telithromycin against 180 isolates (isolated in the year 2000) of Streptococcus agalactiae (n = 33), Enterococcus faecalis (n = 22), Neisseria gonorrhoeae (n = 30), Peptostreptococcus anaerobius (n = 20), Finegoldia magna (n = 20), Bacteroides fragilis (n = 25) and Prevotella bivia (n = 30) was compared with that of erythromycin A, clarithromycin, azithromycin, ampicillin and levofloxacin. In the in vivo study, the efficacy of telithromycin was evaluated using experimental intra-abdominal abscesses in mice caused by B. fragilis (minimum inhibitory concentration of telithromycin 0.5 mg/l).


RESULTS
In the in vitro study, telithromycin inhibited more than 50% of clinical isolates of S. agalactiae, E. faecalis, N. gonorrhoeae, P. anaerobius, F. magna, B. fragilis and P. bivia at concentrations of 0.016, 0.063, 0.063, 0.032, 0.032, 0.5 and 0.25 mg/l, respectively. Telithromycin inhibited more than 90% of these clinical isolates at concentrations of 0.016, 4, 0.125, 0.063, 0.063, 4 and 1 mg/l, respectively. In the in vivo study, telithromycin inhibited abscess formation and significantly decreased viable cell counts in abscesses in comparison with the untreated group.


CONCLUSIONS
These in vitro and in vivo antibacterial activities suggest that telithromycin could be a potential candidate for the treatment of bacterial infections complicated by chlamydial infection.
Mikamo
Hiroshige
H
Department of Obstetrics and Gynecology, Gifu University School of Medicine, Gifu, Japan. mikamo@cc.gifu-u.ac.jp
Yin
Xiang-Hua
XH
Ninomiya
Mochiyoshi
M
Tamaya
Teruhiko
T
D018784:Abdominal Abscess / Q000188:drug therapy*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001424:Bacterial Infections / Q000188:drug therapy; D001438:Bacteroidaceae / Q000187:drug effects*; D001441:Bacteroides fragilis / Q000187:drug effects; D013293:Enterococcus faecalis / Q000187:drug effects; D005260:Female; D005831:Genital Diseases, Female / Q000188:drug therapy / Q000382:microbiology; D016946:Gram-Negative Aerobic Rods and Cocci / Q000187:drug effects*; D006095:Gram-Positive Cocci / Q000187:drug effects*; D048628:Ketolides; D018942:Macrolides / Q000494:pharmacology*; D051379:Mice; D008826:Microbial Sensitivity Tests; D009344:Neisseria gonorrhoeae / Q000187:drug effects; D010462:Peptostreptococcus / Q000187:drug effects; D018720:Prevotella / Q000187:drug effects; D013292:Streptococcus agalactiae / Q000187:drug effects
D000900:Anti-Bacterial Agents; D048628:Ketolides; D018942:Macrolides; C106791:telithromycin