From the Guidelines
The treatment for Pasteurella infections typically involves amoxicillin-clavulanate (875/125 mg orally twice daily for 7-10 days) as the first-line therapy. This recommendation is based on the guidelines from the Infectious Diseases Society of America, as outlined in the 2014 update 1. For patients with penicillin allergies, alternatives include doxycycline (100 mg orally twice daily), trimethoprim-sulfamethoxazole (one double-strength tablet twice daily), or fluoroquinolones like ciprofloxacin (500 mg orally twice daily) 1.
Key Considerations
- Pasteurella multocida, the most common species, is typically susceptible to penicillins but resistant to dicloxacillin, nafcillin, and first-generation cephalosporins 1.
- These infections often result from animal bites, particularly from cats and dogs, and can cause cellulitis, abscess formation, or more serious complications like septic arthritis or osteomyelitis if left untreated.
- Prompt treatment is essential, especially for immunocompromised patients who are at higher risk for invasive disease.
Treatment Options
- For severe infections requiring hospitalization, intravenous ampicillin-sulbactam (1.5-3 g every 6 hours) or piperacillin-tazobactam (3.375 g every 6 hours) is recommended 1.
- Fluoroquinolones, such as ciprofloxacin, levofloxacin, or moxifloxacin, can be used as alternative therapy, especially in patients with penicillin allergies 1.
- Metronidazole can be added to the treatment regimen for coverage of anaerobic organisms, but it should not be used as monotherapy due to its lack of activity against aerobes 1.
Important Notes
- Cultures are often not done on wounds, and empirical therapy might miss pathogens, highlighting the importance of considering the bacteriology of the wound when selecting therapy 1.
- Broader empirical coverage for abscesses might yield better therapeutic results, while a more focused therapy for nonpurulent infected wounds could allow narrower therapy 1.
From the FDA Drug Label
Doxycycline is also indicated for the treatment of infections caused by the following gram-negative microorganisms: Plague due to Yersinia pestis (formerly Pasteurella pestis). Tularemia due to Francisella tularensis (formerly Pasteurella tularensis).
The treatment for Pasteurella infection is doxycycline. Key points to consider:
- Doxycycline is indicated for the treatment of infections caused by gram-negative microorganisms, including those formerly classified as Pasteurella.
- Pasteurella pestis and Pasteurella tularensis are now classified as Yersinia pestis and Francisella tularensis, respectively, and are included in the indications for doxycycline treatment 2.
From the Research
Treatment Options for Pasteurella Infection
- Penicillin or amoxicillin is considered the agent of choice for therapy, as reported in 3.
- Alternate oral agents to penicillins that may be appropriate for therapy of P. multocida infections include ampicillin, amoxicillin/clavulanate, cefprozil, cefuroxime, erythromycin, clarithromycin, trimethoprim/sulfamethoxazole, ciprofloxacin, and tetracycline, as identified in 3.
- All isolates of Pasteurella spp. were susceptible to minocycline, cefotaxime, ofloxacin, ciprofloxacin, and levofloxacin, as found in 4.
- Most strains were susceptible to moxifloxacin, amoxicillin, azithromycin, and clarithromycin, although lower susceptibility rates to telithromycin were observed among respiratory tract isolates, as reported in 4.
- A case of drug-resistant P. multocida prosthetic knee infection was successfully treated with debridement, antibiotics, and implant retention, as described in 5.
Considerations for Treatment
- The therapeutic dilemma of the penicillin-allergic patient and the polymicrobial nature of some infections should be considered when selecting a treatment option, as noted in 3.
- The risk of adverse effects, such as cholestatic hepatitis, should be considered when using amoxicillin/clavulanate, as reported in 6.
- The efficacy of amoxicillin-clavulanate compared to other antibiotics, such as ciprofloxacin, should be considered when treating uncomplicated cystitis, as found in 7.