From the Guidelines
For a cat bite with signs of infection, including fever, induration, and surrounding edema and erythema, immediate treatment with amoxicillin-clavulanate 875/125 mg orally twice daily for 5-7 days is recommended. This regimen is based on the guidelines for the diagnosis and management of skin and soft tissue infections, as outlined in the 2014 update by the Infectious Diseases Society of America 1. The choice of amoxicillin-clavulanate is due to its excellent activity against Pasteurella multocida, a common pathogen in cat bites, as well as its coverage of other potential pathogens, including streptococci and anaerobes.
Key Considerations
- The patient's temperature of 38.2°C and signs of local infection, such as induration of the thenar eminence and circumferential edema and erythema, indicate the need for prompt antibiotic treatment.
- The wound should be thoroughly cleaned with normal saline and debrided if necessary to prevent further infection.
- Tetanus prophylaxis should be administered if the patient's immunization status is not up to date.
- Close follow-up within 24-48 hours is essential to monitor for improvement or progression of infection.
Alternative Treatments
- For patients with penicillin allergy, alternatives include doxycycline 100 mg twice daily, trimethoprim-sulfamethoxazole plus clindamycin, or a fluoroquinolone plus clindamycin, as recommended by the guidelines 1.
- Hospitalization with intravenous antibiotics, such as ampicillin-sulbactam, piperacillin-tazobactam, or a carbapenem, should be considered if there are signs of severe infection, systemic symptoms, or immunocompromise.
From the Research
Treatment for Cat Bite Infection
The patient's symptoms, including a temperature of 38.2, induration of the CR eminence, and circumferential edema and erythema, suggest a cat bite infection. The most common cause of such infections is Pasteurella multocida.
Antimicrobial Therapy
- Penicillin or amoxicillin is considered the agent of choice for therapy 2.
- Amoxicillin/clavulanate is also effective against P. multocida, with a MIC90 of ≤ 0.5 μg/mL 2.
- Other oral antimicrobial agents, such as cefprozil, cefuroxime, and trimethoprim/sulfamethoxazole, may also be effective 2.
- However, the emergence of drug-resistant P. multocida may alter the therapeutic approach to animal bites in the future 3.
Choice of Antibiotic
- Amoxicillin/clavulanate is a commonly prescribed antibiotic for skin infections, including those caused by animal bites 4, 5.
- However, the use of amoxicillin/clavulanate may be limited by the potential for gastrointestinal side effects and the emergence of resistance 4, 5.
- The choice of antibiotic should be guided by the severity of the infection, the patient's medical history, and the susceptibility patterns of the causative organism 2, 3.