What is the appropriate acute management, including wound care, infection prophylaxis, tetanus immunization update, and follow‑up, for a healthy 16‑year‑old adolescent with a deep human bite wound inflicted by a classmate?

Management of Deep Human Bite Wound in a 16-Year-Old

This deep human bite requires immediate copious irrigation with sterile saline, prophylactic antibiotics with amoxicillin-clavulanate, wound approximation with adhesive strips (not sutures unless facial), tetanus prophylaxis if last dose was >5 years ago, and 24-hour follow-up to prevent serious infectious complications including septic arthritis and osteomyelitis. 1

Immediate Wound Care

Irrigate the wound copiously with sterile normal saline using a ≥20 mL syringe to generate sufficient mechanical pressure for debris removal. 2, 1 This mechanical irrigation is as critical as antibiotic prophylaxis for infection prevention. 3 Continue irrigation until all visible debris is removed. 1

• Remove only superficial debris; avoid aggressive debridement that could enlarge the wound or impair healing. 2
• Do not use iodine-containing or antibiotic-containing solutions for irrigation—sterile saline or tap water is superior. 1

Wound Closure Decision

Do not close this wound with sutures unless it is on the face. 2, 1 Human bites have significantly higher infection rates than other wounds, particularly on hands and extremities. 2

• If the wound is NOT on the face: approximate the wound margins with Steri-Strips only, allowing for drainage and delayed healing by secondary intention. 2
• If the wound IS on the face: primary closure after meticulous irrigation and prophylactic antibiotics is acceptable, as facial wounds have lower infection rates and better cosmetic outcomes with early closure. 2, 1
• Never close wounds that already show signs of infection (purulent drainage, erythema, warmth). 2

Critical Pitfall: Hand and Clenched-Fist Injuries

If this bite is on the hand or occurred during a fight (clenched-fist injury), there is extremely high risk for deep structure involvement including joint capsule, tendon, and bone penetration. 2, 1 Pain disproportionate to the visible injury suggests periosteal or joint involvement. 2 These injuries require hand surgery consultation and should never be closed primarily. 1

Antibiotic Prophylaxis

Administer amoxicillin-clavulanate 875 mg/125 mg orally twice daily for 3-5 days as first-line prophylaxis. 1 This regimen covers the polymicrobial flora of human bites, including Streptococcus species (present in 50% of wounds), Staphylococcus aureus (40%), Eikenella corrodens (~30%), and anaerobes such as Fusobacterium, Prevotella, and Bacteroides. 1

Alternative Regimens

• For penicillin allergy: doxycycline 100 mg orally twice daily. 2
• Alternative oral options: penicillin VK plus dicloxacillin, or a fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin) plus metronidazole or clindamycin for anaerobic coverage. 1

Critical Pitfall: Inadequate Antibiotic Coverage

Never use first-generation cephalosporins (cephalexin), macrolides (erythromycin), or clindamycin alone—these lack activity against Eikenella corrodens, a common human bite pathogen. 2, 3

Tetanus Prophylaxis

Verify the patient's tetanus immunization history thoroughly. 2 For this 16-year-old with a deep, contaminated wound:

• If last tetanus-containing vaccine was >5 years ago: administer Tdap (preferred over Td for adolescents 11-18 years who have not previously received Tdap). 2
• If last vaccine was <5 years ago and primary series is complete: no tetanus vaccine needed. 2
• If immunization history is unknown or incomplete: consider the patient unvaccinated and administer both tetanus toxoid-containing vaccine AND tetanus immune globulin (TIG) at separate anatomic sites. 2

The rationale: deep wounds create anaerobic conditions favorable for Clostridium tetani, and adolescents often have waning immunity if their last booster was in early childhood. 4, 5

Blood-Borne Pathogen Assessment

Human bites can transmit hepatitis B, hepatitis C, and HIV. 1 Assess the need for post-exposure prophylaxis based on:

• Baseline serology of the victim
• Viral status of the biter (if obtainable)
• CDC guidelines for PEP decision-making 1

Rabies transmission from human bites is extraordinarily rare in the United States and prophylaxis is typically not indicated unless the biting person has suspected rabies exposure. 1

Elevation and Supportive Care

Elevate the injured body part, especially if swollen, to accelerate healing and reduce edema. 2, 1 Use a sling for outpatients or passive elevation methods. 2

Follow-Up and Monitoring

Schedule follow-up within 24 hours (by phone or office visit) to assess for infection. 2, 1 Instruct the patient to return immediately for:

• Increasing pain, redness, swelling, or warmth
• Purulent or foul-smelling drainage
• Fever or systemic symptoms
• Red streaking (lymphangitis) 1

If infection develops despite appropriate therapy, consider hospitalization and intravenous antibiotics (ampicillin-sulbactam, piperacillin-tazobactam, or carbapenems). 1

Duration of Therapy for Complications

• Septic arthritis: 3-4 weeks of antibiotics 2, 1
• Osteomyelitis: 4-6 weeks of antibiotics 2, 1

Summary Algorithm

1. Irrigate copiously with sterile saline using high-pressure syringe 2, 1
2. Do NOT suture unless facial wound 2, 1
3. Start amoxicillin-clavulanate 875/125 mg BID × 3-5 days 1
4. Give Tdap if last dose >5 years ago (or Tdap + TIG if unvaccinated) 2
5. Assess blood-borne pathogen risk and consider PEP 1
6. Elevate the injured area 2, 1
7. Follow up in 24 hours 2, 1
8. Refer to hand surgery if hand/clenched-fist injury 1

Human bites are more dangerous than animal bites due to their polymicrobial nature and high complication rates, particularly when involving hands or deep structures. 2, 1 Early aggressive management prevents morbidity from septic arthritis, osteomyelitis, and systemic infection. 2, 1