Comparative effect of gentamicin and pefloxacin treatment on the late stages of mouse typhoid
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L Bonina1, G B Costa, P Mastroeni
1Istituto di Microbiologia, Università di Messina, Italy.
Abstract:
The present study compares the ability of gentamicin and pefloxacin to eradicate a Salmonella infection in BALB/c mice when the treatment is instituted in the late stages of the infection. The results indicate that pefloxacin is highly effective in the treatment of mouse typhoid even when the therapy is instituted after the suppression of bacterial growth in the reticuloendothelial system (RES). Conversely, gentamicin treatment only reduced the bacterial load in the RES of infected mice, but neither induced the clearance of the organisms from the RES, nor prevented the resurgence of bacterial growth. Even when using gentamicin at a high dosage, bacterial clearance could not be accomplished.
Insights
Pefloxacin effectively eradicated Salmonella in mice late in infection, clearing bacteria from the reticuloendothelial system (RES). Gentamicin only reduced bacterial load in the RES, failing to prevent regrowth.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Salmonella infections pose a significant threat, causing diseases like mouse typhoid.
- Late-stage treatment of bacterial infections presents therapeutic challenges.
- The reticuloendothelial system (RES) is a critical site for Salmonella replication.
Purpose of the Study:
- To compare the efficacy of pefloxacin and gentamicin in eradicating Salmonella infections in mice.
- To evaluate treatment effectiveness when initiated in the late stages of infection.
- To assess the impact of these antibiotics on bacterial load within the RES.
Main Methods:
- BALB/c mice were infected with Salmonella.
- Treatment with gentamicin or pefloxacin was initiated in the late stages of infection.
- Bacterial load in the reticuloendothelial system (RES) was assessed post-treatment.
Main Results:
- Pefloxacin demonstrated high efficacy, eradicating Salmonella even when treatment started late.
- Pefloxacin successfully cleared bacteria from the RES.
- Gentamicin reduced bacterial load in the RES but did not achieve clearance or prevent regrowth.
- High-dose gentamicin also failed to accomplish bacterial clearance from the RES.
Conclusions:
- Pefloxacin is a highly effective therapeutic agent for late-stage Salmonella infections in mice.
- Gentamicin is less effective, failing to clear Salmonella from the RES and prevent recurrence.
- Treatment timing and drug choice are critical for successful Salmonella eradication, particularly concerning RES involvement.
