Cat Bite Treatment
Cat bites require immediate thorough wound cleansing with soap and water for 15 minutes, and prophylactic antibiotics with amoxicillin-clavulanate should be started for all patients, particularly given the 30-50% infection rate—the highest among all animal bites. 1, 2
Immediate Wound Management
- Irrigate the wound thoroughly with soap and water for approximately 15 minutes to reduce infection risk and potential rabies transmission 2, 3
- Examine the wound carefully for depth, tendon involvement, bone penetration, or joint capsule involvement—pain disproportionate to injury near a bone or joint suggests deeper penetration 2, 3
- Do not suture cat bite wounds except for facial wounds seen early (within hours) that have been properly cleaned, as closure increases infection risk in these high-risk wounds 1, 3
- Debride any necrotic tissue present 1
Antibiotic Prophylaxis (Critical for Cat Bites)
Start antibiotics immediately—do not wait for signs of infection. Cat bites have a 30-50% infection rate, significantly higher than dog bites (5-25%), making prophylaxis essential rather than optional 1, 4.
First-Line Antibiotic
Penicillin-Allergic Patients
Avoid These Antibiotics
- First-generation cephalosporins, penicillinase-resistant penicillins, macrolides, and clindamycin alone have poor activity against Pasteurella multocida (present in >50% of cat bites) and should not be used 3, 4
Duration
- 3-5 days for prophylaxis in fresh wounds 1
- 4 weeks for septic arthritis, 6 weeks for osteomyelitis if these complications develop 1
High-Risk Wounds Requiring Aggressive Treatment
Cat bites to the following locations warrant particular concern:
- Hand wounds have the greatest infection risk and most serious complications, including septic arthritis, osteomyelitis, and flexor tenosynovitis 4, 5, 6
- Wounds over joints, tendons, ligaments, or bones 2, 3
- Deep puncture wounds (most common cat bite type) 5
- Wounds in immunocompromised patients 2
Tetanus Prophylaxis
- Assess tetanus immunization status and administer tetanus toxoid if the patient has unknown or incomplete immunization 2, 3
Rabies Prophylaxis
- Assess need based on the cat's vaccination status, whether the cat can be observed for 10 days, and local rabies prevalence 2
- Contact local health department for guidance 1
- If indicated, administer both rabies immune globulin and rabies vaccine immediately 2
Microbiology of Cat Bites
Cat bite wounds are polymicrobial with mixed aerobic and anaerobic bacteria:
- Pasteurella multocida is isolated in over 50% of cat bite wounds and can cause serious infection with severe complications 4, 7, 8
- Staphylococcus and Streptococcus species (including MRSA) 1, 7
- Anaerobes including Fusobacterium, Prevotella, Bacteroides, and Porphyromonas species 1
- Capnocytophaga canimorsus can cause fatal sepsis, especially in asplenic or immunocompromised patients 2, 3
Complications to Monitor
- Wound infection develops in 30-50% of cat bites, particularly puncture wounds and hand wounds 1, 5
- Septic arthritis and osteomyelitis, especially with hand wounds 1, 2, 3
- Flexor tenosynovitis in hand wounds 6
- Subcutaneous abscess formation and tendonitis 2, 3
- Bacteremia and sepsis, particularly in elderly or immunocompromised patients 8
Critical Pitfalls to Avoid
- Never dismiss cat bites as minor injuries—they have double the infection rate of dog bites 7
- Do not delay antibiotic prophylaxis—patients presenting >24 hours after injury have significantly higher infection rates and often require hospital admission for complications 5, 6
- Hand wounds require special attention—six of nine patients presenting late with hand wounds in one study required admission for tendon lesions or purulent tenosynovitis 6
- Elderly patients are at higher risk for severe complications including sepsis and renal failure 8