zithromax and grepafloxacin

The prophylactic potential of the azalide azithromycin as well as the fluoroquinolones trovafloxacin and grepafloxacin was assessed for the control of infection with Brucella melitensis in an experimental mouse model, determined by reduction in splenic bacterial burden. Trovafloxacin showed limited protective efficacy when administered 2h following a low-dose B. melitensis challenge, whereas grepafloxacin was ineffective. In comparison, azithromycin provided significant control of infection both following low- and high-dose challenges. Overall, the data confirm the potential utility of azithromycin in the prophylaxis of brucellosis and suggest that neither trovafloxacin nor grepafloxacin would likely be valuable for post-exposure prophylaxis of Brucella infection.

Topics: Animals; Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Brucella melitensis; Brucellosis; Colony Count, Microbial; Disease Models, Animal; Female; Fluoroquinolones; Humans; Mice; Mice, Inbred BALB C; Naphthyridines; Piperazines; Spleen

The efficacies of the azalide azithromycin and the fluoroquinolones trovafloxacin and grepafloxacin for pre- and post-exposure prophylaxis of infection with high or low challenge doses of Burkholderia pseudomallei strain 576 were assessed in an experimental mouse model. Trovafloxacin and grepafloxacin afforded significant levels of protection, whereas azithromycin was ineffective and potentially detrimental. Overall, the data suggest that some fluoroquinolones may have potential utility in prophylaxis of melioidosis and suggest that azithromycin would not be effective in prophylaxis of B. pseudomallei infection.

Topics: Animals; Anti-Bacterial Agents; Antibiotic Prophylaxis; Azithromycin; Burkholderia pseudomallei; Disease Models, Animal; Female; Fluoroquinolones; Humans; Melioidosis; Mice; Mice, Inbred BALB C; Naphthyridines; Piperazines; Survival Analysis

In Japan, antimicrobial agent therapy for patients with diarrhea due to enterovirulent organisms including enterohemorrhagic Escherichia coli (EHEC) is common, and norfloxacin (NFLX), fosfomycin, and kanamycin are recommended for EHEC treatment by the Japanese Ministry of Health and Welfare. The aim of this study was to analyze the effects of antimicrobial agents which have been used or recommended for the treatment of EHEC on the production of verotoxin (VT) in vitro. Subinhibitory concentrations of quinolones, NFLX, sparofloxacin (SPFX), and grepafloxacin (GPFX) markedly stimulated the productions of VT1 and VT2. The macrolide azithromycin (AZM), erythromycin (EM), and clarithromycin (CAM) did not stimulate the production of VT at a wide range of concentrations. These in vitro results indicate that when quinolones are prescribed for a patient infected with EHEC, the concentration of antimicrobial agents used in vivo and the susceptibility of the EHEC strains against quinolones should be taken into consideration.

Topics: Animals; Anti-Infective Agents; Azithromycin; Bacterial Toxins; Chlorocebus aethiops; Clarithromycin; Dose-Response Relationship, Drug; Enterotoxins; Erythromycin; Escherichia coli O157; Fluoroquinolones; Humans; Macrolides; Norfloxacin; Piperazines; Quinolones; Shiga Toxin 1; Time Factors; Vero Cells