Treatment of Cat Scratch Wound in Up-to-Date Vaccinated Patient
For a simple cat scratch in an immunocompetent, up-to-date vaccinated patient, immediately wash the wound thoroughly with soap and water, then initiate prophylactic amoxicillin-clavulanate 875/125 mg twice daily for 3-5 days if the scratch is deep, on the hand/foot/face, or near a joint. 1
Immediate Wound Management
- Promptly wash the scratch with soap and water immediately after injury—this is the single most important intervention to reduce bacterial inoculation and prevent both routine wound infection and cat scratch disease (Bartonella henselae). 2, 1
- Cleanse with sterile normal saline to remove superficial debris; iodine or antibiotic solutions are unnecessary. 1
- Deep debridement is not needed unless significant devitalized tissue is present. 1
- Do not close the wound primarily if any signs of infection are present. 1
Tetanus Status Verification
- Administer 0.5 mL tetanus toxoid intramuscularly if the last dose was >5 years ago (for this contaminated wound) or >10 years for clean wounds. 1
Antibiotic Prophylaxis Decision Algorithm
Initiate prophylactic antibiotics if ANY of the following apply:
- Deep puncture wound 1
- Location on hands, feet, face, or near joints (hand injuries carry highest infection risk) 1
- Patient is immunocompromised 1
- Significant swelling or signs of early infection 1
First-line regimen: Amoxicillin-clavulanate 875/125 mg orally twice daily for 3-5 days provides optimal coverage against Pasteurella multocida (present in ~75% of cat wounds), staphylococci, streptococci, and anaerobes. 1
Alternative Regimens for Penicillin Allergy
- Doxycycline 100 mg orally twice daily is the preferred alternative with excellent Pasteurella activity. 1
- Fluoroquinolones (ciprofloxacin 500-750 mg twice daily or levofloxacin 750 mg daily) provide good coverage but may require additional metronidazole for anaerobic coverage. 1
- Trimethoprim-sulfamethoxazole plus metronidazole is another option. 1
Avoid these antibiotics (poor Pasteurella coverage): first-generation cephalosporins, dicloxacillin, macrolides as monotherapy, or clindamycin alone. 1
Monitoring for Cat Scratch Disease (Bartonella henselae)
Cat scratch disease is a separate entity from acute wound infection and typically presents 3-30 days after the scratch with a papule/pustule, followed by regional lymphadenopathy at ~3 weeks. 2, 3
If lymphadenopathy develops:
- Azithromycin is first-line treatment: 500 mg on day 1, then 250 mg daily for 4 more days (for patients >45 kg), or 10 mg/kg day 1 then 5 mg/kg for 4 days (for patients <45 kg). 2, 3
- Alternative: Doxycycline 100 mg twice daily for 10-14 days if azithromycin is contraindicated. 2, 1
- Most cases in immunocompetent patients are self-limited and resolve within 1-6 months without treatment, but antibiotics speed lymph node resolution. 2, 4
Red Flags Requiring Urgent Evaluation
- Pain disproportionate to the apparent injury, especially near bone or joint, suggests possible septic arthritis or osteomyelitis. 1
- Progressive infection despite appropriate oral antibiotics requires hospitalization and IV therapy (ampicillin-sulbactam 1.5-3.0 g every 6-8 hours). 1
- Hand wounds require closer monitoring than scratches on other body parts due to higher complication risk. 1
Adjunctive Measures
- Elevate the injured limb if swelling is present; passive elevation accelerates healing during the first few days. 1
Special Considerations
Rabies risk: Generally unnecessary for domestic indoor cats, but consider post-exposure prophylaxis for scratches from unknown, feral, or wild cats—consult local health department. 1
Immunocompromised patients: Require more aggressive management with lower threshold for antibiotics and vigilance for atypical presentations including bacillary angiomatosis and disseminated disease. 2, 1