Bite Wounds

#med #disease #id

Presentation :

Human bites:
- Intentional biting of others, self-inflicted wounds such as those occurring from fingernail biting, and clenched-fist injuries after a punch to another person's moudisth are the most common causes of human bite wounds

Animal bites:
- The microbiology of infection depends on the microbiota of the animal's mouth and of the patient's skin. Mixed aerobes and anaerobes, including staphylococci, streptococci, Bacteroides species, Porphyromonas species, Fusobacterium species, and Pasteurella species, typically compose the bacteria in bite wounds. Capnocytophaga canimorsus is a common constituent of canine microbiota and can cause severe infections in patients with asplenia.
Human bites:
- at risk for infection with human skin and mouth organisms. These organisms comprise aerobic organisms, including staphylococci, streptococci, and Eikenella corrodens, and anaerobic organisms, including Peptostreptococcus, Fusobacterium, and Prevotella species

Animal bite:
- No e/o infxn: No treatment
  - 3-5d of amoxicillin-clavulanate is recommended for patients who are immunosuppressed (including cirrhosis and asplenia), for wounds with associated edema or lymphatic or venous insufficiency; crush injury; joint or bone involvement; deep punctures; or moderate to severe injuries, especially involving the face, genitalia, or hand
- Clinically infected:
  - All should get tissue wound culture (blood cx if e/o systemic infxn)
  - Mild: Amox-clauv, bactrim, doxy/fluoroquinolone + clinda/metronidazole
  - Severe (systemic sx, tendon/nerve/vascular/crush injuries; hand involvement): Unasyn, Zosyn, carbapenem, CTX/Fluoroquinolone + clinda/metronidazole
- Be sure to assess need for rabies + tetanus vaccination
Human bite (breaking skin):
- All get prophylactic amox-clauv x3-5d
- Assess for blood-bourne diseases (HIV, Hep B/C)
- Clinically infected:
  - Mild: cephalexin, clindamycin, amoxicillin-clavulanate, or dicloxacillin
  - Mod-Severe: Deep tissue culture => β-lactam/β-lactamase (unasyn, zosyn), carbapenems, or CTX/Fluoroquinolone + metronidazole;
  - If MRSA risk factors or purulent:
    - Mild: Doxy, Bactrim
    - Mod-Severe: Vancomycin, daptomycin, linezolid
Hand wounds:
- Surgical evaluation/exploration for possible debridement and removal of foreign bodies