Rosen & Barkin's 5-Minute Emergency Medicine Consult (104 page)

• Amoxicillin/clavulanic acid (Augmentin): 500/125 mg (peds: 40 mg/kg/24h) q8h PO
  
• Ampicillin–sulbactam (Unasyn): 3 g q6h IV
  
• Penicillin 1–2 million units q6h IV (peds 20,000–50,000 U/kg/d div. q4h IV)
  
• Piperacillin–Tazobactam (Zosyn): 4.5 g q8h IV
  
• Ticarcillin–clavulanate (Timentin): 3.1 g q4h IV
  
• Ceftriaxone (Rocephin): 1 g/d plus Metronidazole (Flagyl): 500 mg q8h
  

• 2 drug therapy: 1 of the following below + anaerobic coverage:
  
  • Trimethoprim–sulfamethoxazole (Septra DS): 1 tablet q12h (peds: 8 mg/kg trimethoprim and 40 mg/kg sulfamethoxazole per day divided into 2 daily doses) PO
    
  • Penicillin (Penicillin VK): 500 mg (peds: 50 mg/kg/24h) PO q6h
    
  • Ciprofloxacin (Cipro): 500–750 mg q12h PO or 400 mg q12h IV
    
  • Doxycycline: 100 mg PO BID
    
• + (anaerobic coverage):
  
  • Clindamycin (Cleocin): 150–450 mg (peds: 8–20 mg/kg/24h) PO q6h or 600–900 mg (peds: 20–40 mg/kg/24h) IV q8h
    
  • Metronidazole (Flagyl): 500 mg PO TID (peds: 10 mg/kg/dose TID)
    

FOLLOW-UP

• All bites:
  
  • Infected wounds at presentation
    
  • Severe/advancing cellulitis/lymphangitis
    
  • Signs of systemic infection
    
  • Infected wounds that have failed to respond to outpatient (PO) antibiotics
    
• Catscratch disease:
  
  • Prolonged fever, systemic symptoms, and/or marked lymphadenopathy
    

• Healthy patient with localized wound infection:
  
  • Discharge on antibiotics with 24-hr follow-up.
    
• Noninfected wounds:
  
  • 48-hr follow-up
    

• Hand specialist referral/follow-up for infected hand wounds.
  
• Healthy patient with localized wound infection: Discharge on antibiotics with 24-hr follow-up.
  
• 48-hr follow-up for noninfected wounds
  

Animal bites must be reported to authorities in many localities.

• Baddour L. Soft tissue infections due to dog and cat bites.
  UpToDate.
  2009.
  
• Brook I. Microbiology and management of human and animal bite wound infections.
  Prim Care
  . 2003;30(1):25–39.
  
• Elliott SP. Rat bite fever and
  Streptobacillus moniliformis
  .
  Clin Microbiol Rev.
  2007;20:13–22.
  
• Galloway RE. Mammalian bites.
  J Emerg Med
  . 1998;6:325–331.
  
• Griego RD, Rosen T, Orengo IF, et al. Dog, cat, and human bites: A review.
  J Am Acad Dermatol
  . 1995;33:1019–1029.
  
• Klein JD. Cat scratch disease.
  Pediatr Rev
  . 1994;15(9):348–353.
  
• Pickering L.
  Red Book: 2003 Report of the Committee on Infectious Diseases
  . 26th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2003.
  
• Smith PF, Meadowcroft AM, May DB. Treating mammalian bite wounds.
  J Clin Pharm Ther
  . 2000;25:85–99.
  
• Trucksis M. Rat-bite fever.
  UpToDate.
  May 6, 2011.
  

See Also (Topic, Algorithm, Electronic Media Element)

Rabies

CODES

• 873.40 Open wound of face, unspecified site, without mention of complication
  
• 874.8 Open wound of other and unspecified parts of neck, without mention of complication
  
• 882.0 Open wound of hand except finger(s) alone, without mention of complication
  

BASICS

• 3rd most common bite (after dogs and cats)
  
• Most bites (up to 75%) occur during aggressive acts.
  
• 15–20% are related to sexual activity (love nips).
  
• 2 types of bites:
  
  • Occlusional bites: Laceration or crush injury to affected body part:
    
    • Occurs when human teeth bite into the skin
      
    • More prone to infection than animal bites
      
  • Clenched-fist injuries (CFIs) (CFIs; most serious type): Present as small wounds over metacarpophalangeal joints in dominant hand (fight bites):
    
    • Sustained from a clenched fist striking the mouth and teeth of another person
      
• With joint relaxation from the clenched position:
  
  • Puncture site sealed
    
  • Oral bacteria inoculated in the anaerobic setting within the joint
    
  • Bacterial inoculation carried by the tendons deeper into the potential spaces of the hand
    
  • Increases chances for a more extensive infection
    

• Aerobic and anaerobic organisms:
  
  • Most common:
    
    • Streptococcus
      
    • Staphylococcus
      
  • Others:
    
    • Eikenella corrodens
      
    • Haemophilus influenzae
      
    • Peptostreptococcus
      
    • Corynebacterium
      
    • E. corrodens
      exhibits synergism with
      Streptococcus
      ,
      Staphylococcus aureus
      ,
      Bacteroides
      , and gram-negative organisms
      
• Although rare, case reports of viral transmission via bites (hepatitis, HIV, and herpes)
  

DIAGNOSIS

• Location:
  
  • Upper extremities (60–75%)
    
  • Head and neck (15–20%)
    
  • Trunk (10–20%)
    
  • Lower extremities (∼5%)
    
• Frequent complications:
  
  • Cellulitis
    
  • Serious deep-space infections (septic arthritis and osteomyelitis)
    
  • Fractures and tendon injuries
    
  • Hand bites have highest rates of infection.
    

• Time of injury
  
• Patient allergies
  
• Relevant medical history (immune status)
  
• Last tetanus shot
  
• HIV, hepatitis B status of person inflicting bite
  

• Record the location and extent of all injuries.
  
• Document any swelling, crush injuries, or devitalized tissue.
  
• Note the range of motion of affected areas.
  
• Note the status of tendon and nerve function.
  
• Document any signs of infection, including regional adenopathy.
  
• Document any joint or bone involvement.
  

Careful physical exam for involvement of deep structures and foreign bodies:

• Examine the deepest part of clenched-fist bites while putting the fingers through full range of motion to check for extensor tendon lacerations and joint violation.
  

• Aerobic and anaerobic cultures from any infected bite wound
  
• Cultures not indicated if wounds not clinically infected
  
• CBC if signs of significant infection.
  
• Electrolytes, glucose, BUN, and creatinine:
  
  • For diabetic patients or those with significant infections
    

• Generally not helpful
  
• Plain radiograph indications:
  
  • Fracture
    
  • Suspect foreign body (e.g., tooth)
    
  • Baseline film if a bone or joint space has been violated in evaluating for osteomyelitis
    
  • For infection in proximity to a bone or joint space
    
• Ultrasound can be useful in differentiating abscess from cellulitis
  

Bite injuries from animals:

• Sharper teeth cause more punctures and lacerations than human teeth, which usually cause more crush-type injuries.