What is the recommended management for a cat bite, including wound care, tetanus update, rabies prophylaxis, and antibiotic therapy?

Cat Bite Management

Cat bites require immediate copious irrigation, prophylactic antibiotics with amoxicillin-clavulanate 875/125 mg twice daily for 3-5 days, tetanus prophylaxis if not current, and wounds should generally NOT be closed except for facial lacerations. 1

Immediate Wound Care

• Irrigate the wound immediately and thoroughly with sterile normal saline or water using a 20-mL or larger syringe to generate adequate pressure for bacterial load reduction 1, 2
• Remove only superficial debris—avoid aggressive debridement that unnecessarily enlarges the wound 1
• Do NOT use iodine-containing or antibiotic-containing solutions for routine wound cleansing 1
• Explore the wound for potential tendon, bone, or joint involvement, which significantly increases complication risk 2

Antibiotic Therapy (Critical Component)

Amoxicillin-clavulanate 875/125 mg twice daily is the first-line antibiotic for all cat bites, providing essential coverage against Pasteurella multocida, the predominant pathogen in 50% of cat bite infections. 1, 3

• Prophylactic antibiotics are strongly indicated for cat bites due to their 30-50% infection rate—the highest among all bite wounds 3
• Hand wounds, wounds near joints or bones, and puncture wounds (typical of cat bites) mandate prophylactic antibiotics 1, 2
• Treatment duration: 3-5 days for prophylaxis, 7-10 days for established infection 1
• For penicillin-allergic patients: doxycycline 100 mg twice daily 1
• AVOID first-generation cephalosporins, macrolides, or clindamycin alone—these have poor activity against Pasteurella multocida 1

Severe Infections Requiring IV Therapy

• Use ampicillin-sulbactam, piperacillin-tazobactam, second-generation cephalosporins (cefoxitin), or carbapenems for severe infections with systemic signs 1, 3
• Extended therapy required for complications: 3-4 weeks for septic arthritis, 4-6 weeks for osteomyelitis 1

Wound Closure Decision

Do NOT close cat bite wounds except for facial lacerations. 1

• Cat bites create deep puncture wounds with high infection risk that contraindicate primary closure 1
• Facial wounds are the ONLY exception—these can be closed primarily after meticulous irrigation and debridement with concurrent prophylactic antibiotics 1
• For non-facial clean wounds seen early (<8 hours), consider approximation with Steri-Strips rather than sutures if needed 1
• Never close infected wounds showing purulent discharge, erythema, or established infection signs 1

Tetanus Prophylaxis

• Administer tetanus toxoid 0.5 mL intramuscularly if vaccination status is outdated or unknown 1
• Cat bites are considered dirty wounds requiring booster if >5 years since last dose 1
• For clean wounds, booster needed if >10 years since last dose 1

Rabies Prophylaxis

• Rabies prophylaxis is generally NOT required for domestic cat bites in the United States 1
• Consult local health department for regional risk assessment, particularly for feral or stray cat bites in high-prevalence areas 1, 3
• If indicated for unvaccinated persons: administer both rabies immune globulin (20 IU/kg infiltrated around wound) and vaccine series on days 0,3,7,14, and 28 3, 2
• Rabies immune globulin should be infiltrated around the wound site with any remaining volume given intramuscularly at a site distant from vaccine administration 3

Special Populations at High Risk

• HIV-infected and immunocompromised patients face increased risk of Bartonella infection (cat scratch disease) from cat bites and scratches 1
• These patients should wash bite and scratch sites promptly and avoid allowing cats to lick open wounds 1
• Flea control reduces Bartonella transmission risk 1
• Immunocompromised patients require lower threshold for hospitalization and IV antibiotics 3

Follow-Up and Monitoring

• Elevate the injured extremity to reduce swelling 1
• Follow-up within 24 hours by phone or office visit is mandatory for all outpatients 1
• Monitor for infection signs: increasing pain, redness, swelling, purulent discharge 1
• Hospitalize if infection progresses despite appropriate antibiotics, deep tissue involvement is suspected, or patient is immunocompromised 1

Common Pitfalls to Avoid

• Do NOT underestimate cat bite infection risk—at 30-50%, it exceeds dog bites (5-25%) and human bites (20-25%) 3
• Do NOT use inadequate antibiotic coverage—first-generation cephalosporins and macrolides fail against Pasteurella multocida 1
• Do NOT close non-facial cat bite wounds—the deep puncture nature creates anaerobic environment favoring infection 1
• Do NOT delay antibiotic initiation—prophylaxis is most effective when started immediately 1, 2