Chemotherapy for enterohemorrhagic Escherichia coli O157 : H infection in a mouse model

The aim of this study is to evaluate the therapeutic effect of the antimicr obial agents, fosfomycin (FOM), minocycline (MINO), kanamycin (KM) and norf loxacin (NFLX) in the enterohemorrhagic Escherichia coli (EHEC) infected mo use model which we established previously (Infect. Immun. 62 (1994) 3447-34 53). Each of the antimicrobial agents, 1/16 LD50, was given to the mice per os (p.o.) or intraperitoneally (i.p.) for 3 days after bacterial inoculati on and then we observed their mortality rate for 2 weeks. The mortality rat es of mice administered with MINO (p.o./i.p.), KM (p.o.), NFLX (p.o./i.p.) were significantly lower than those of the control group. Both the bacteria ! number and VT2c level in the feces of the FOM group were lower than those of the NFLX group on day 1, but reversed on day 3. In an in vitro experime nt, each of the four drugs in combination with mitomycin C (MMC) caused a m ore significant decrease in the bacterial number than sole MMC, and they co nsequently indicated the suppressive effect on the release of VT2c. (C) 199 9 Federation of European Microbiological Societies. Published by Elsevier S cience B.V. All rights reserved.