In vitro and in vivo antibacterial activities of AM-1155 in the fields of obstetrics and gynecology.

AM-1155 is a new 8-methoxyquinolonecarboxylic acid with a broad spectrum of antibacterial activity. It inhibited more than 90% of clinical isolates of Streptococcus agalactiae, Escherichia coli, Peptostreptococcus magnus, Bacteroides fragilis and Prevotella bivia at the concentration of 3.13 mg/l. The antibacterial activity of AM-1155 was almost equal to that of sparfloxacin. The in vivo efficacy of AM-1155 was evaluated using a polymicrobial pyometra (E. coli and B. fragilis) model of rats. The accumulation of neutrophils to the uterus in the AM-1155-treated group was less marked than that of the nontreated group, as well as the bacteriological response. These results suggest that the new antimicrobial agent AM-1155 might be useful for the treatment of polymicrobial infections in the fields of obstetrics and gynecology.