Rifampicin and rifapentine in treatment of experimental listeriosis in normal mice and athymic (nude) mice.

Rifampicin and rifapentine were used in the treatment of Listeria monocytogenes infections in normal mice and congenitally athymic (nude) mice. Results were compared with untreated controls and with the results obtained from a previous study of ampicillin in which this model was used. Low doses of rifampicin or rifapentine were adequate to cure normal mice. The efficacy of these antibiotic treatment schedules was lost in nude mice. Prolonged antibiotic treatment schedules with increased dosages were also unsuccessful. These studies show that rifampicin and rifapentine , two antimicrobial agents being capable of destroying intracellular bacteria, were not effective in curing the Listeria infection in mice with impaired host defenses.