What is the recommended treatment for an infected cat bite?

Treatment of Infected Cat Bites

Amoxicillin-clavulanate (875/125 mg twice daily) is the recommended first-line treatment for infected cat bites due to its excellent coverage against common pathogens including Pasteurella multocida. 1

Microbiology and Risk Factors

Cat bites have a high risk of infection (20-80%) compared to dog bites (3-18%) 2, 3. This is primarily due to:

• High prevalence (approximately 90%) of Pasteurella multocida in the feline oral cavity 3
• Deep puncture wounds from cats' sharp teeth that can inoculate bacteria into tissues
• Common pathogens include:
  • Pasteurella multocida (found in >50% of cat bite wounds)
  • Streptococcus species
  • Staphylococcus species
  • Anaerobic bacteria

Treatment Algorithm

First-Line Therapy:

• Amoxicillin-clavulanate 875/125 mg twice daily 1
  • Provides excellent coverage against Pasteurella multocida and other common pathogens
  • High susceptibility rates (100%) have been documented for this antibiotic 3

Alternative Options (for penicillin-allergic patients):

• Doxycycline 100 mg twice daily 1
  • Excellent activity against Pasteurella multocida
  • Some streptococci may be resistant
• Clindamycin 300 mg three times daily 1
  • Good activity against staphylococci, streptococci, and anaerobes
  • Misses Pasteurella multocida

For Severe Infections Requiring IV Therapy:

• Ampicillin-sulbactam 1.5-3.0 g every 6-8 hours 1
• Piperacillin-tazobactam 3.37 g every 6-8 hours 1

Wound Management

In addition to antibiotic therapy, proper wound management is crucial:

• Thorough irrigation and cleaning of the wound
• Debridement of necrotic tissue if present
• Elevation of affected limb if possible
• Close monitoring for signs of spreading infection

Special Considerations

• Treatment Duration: 7-10 days is typically recommended for infected cat bites 1
• Tetanus Prophylaxis: Ensure tetanus vaccination is current
• Follow-up: Patients should return if symptoms worsen after 48 hours of antibiotics, fever develops or increases, or redness/swelling continues to spread

When to Consider Alternative Diagnoses

If the wound fails to respond to appropriate first-line therapy:

• Consider rare pathogens such as Mycobacterium chelonae 4
• Consider obtaining wound cultures to guide targeted therapy
• Evaluate for deeper tissue involvement or abscess formation

Monitoring

Monitor for:

• Spreading erythema or cellulitis
• Systemic symptoms (fever, chills)
• Lymphadenopathy
• Development of deeper tissue infections

Early and appropriate antibiotic therapy with amoxicillin-clavulanate remains the cornerstone of treatment for infected cat bites, with excellent outcomes when initiated promptly.