II. Causes: Bacterial Infection

  1. See Animal Bite
  2. Pasteurella multocida (20-50% of all dog and Cat Bite infections)
    1. Typically Cat Bites, but can occur in Dog Bites as well
    2. Infection rapid onset (<24 hours) and progression is typical of P. multocida
  3. Streptococcus
  4. Staphylococcus aureus
  5. Escherichia coli
  6. Moraxella
  7. Corynebacterium
  8. Neisseria
  9. Anaerobic Bacteria
    1. Bacteroides
    2. Fusobacterium
    3. Peptostreptococcus
  10. Capnocytophaga canimorsus (DF-2)
    1. Emerging Infection in dog and Cat Bites with risk of secondary Sepsis, Meningitis, endocarditis, DIC, Acute Renal Failure
    2. Increased risk in patients s/p splenectomy or with Alcohol Abuse (or other immunocompromised state)
    3. Gram Negative Bacteria responds to Augmentin

III. Risk Factors: Infection

  1. Wound Type
    1. Crush Injury
    2. Puncture Wound
    3. Hand Wound
  2. Underlying Disease
    1. Chronic Disease
    2. Chronic extremity edema
    3. Diabetes Mellitus
    4. Immunosuppression
    5. Liver disease
    6. Prior Mastectomy
    7. Prosthetic Valve
    8. Prosthetic Joint
    9. Asplenia (post-splenectomy)
    10. Systemic Lupus Erythematosus (SLE)

IV. Management: Outpatient antibiotics

  1. Antibiotic duration guidelines
    1. Prophylaxis after Dog Bite: 7 days
    2. Cellulitis Present: 10 to 14 days
  2. First Line antibiotics (adults and children)
    1. Amoxicillin-Clavulanate (Augmentin)
      1. Child: 45 mg/kg/day divided twice daily up to 875 mg twice daily
      2. Adult: 875 mg twice daily
  3. Alternative Antibiotics for Penicillin Allergic
    1. Adults
      1. Doxycycline 100 mg orally twice daily (do not use in pregnancy)
      2. Combination protocol: Clindamycin with Ciprofloxacin
        1. Clindamycin 300 mg every 8 hours AND
        2. Ciprofloxacin 500 mg twice daily (or other Fluoroquinolone)
      3. Combination protocol: Cefuroxime with Metronidazole
        1. Cefuroxime (Ceftin) 500 mg twice daily AND
        2. Metronidazole (Flagyl), 250 to 500 mg four times daily
      4. Combination protocol: Clindamycin with Trimethoprim-Sulfamethoxazole
        1. Clindamycin 300 mg every 8 hours AND
        2. Trimethoprim-Sulfamethoxazole (Bactrim, Septra) DS twice daily
      5. Combination protocol: Penicillin VK with Dicloxacillin
        1. Penicillin VK 500 mg 4 times daily AND
        2. Dicloxacillin 500 mg 4 times daily
    2. Pregnancy
      1. Azithromycin (Zithromax), 250 to 500 mg daily
      2. Monitor closely to high risk of treatment failure
    3. Children
      1. Combination protocol
        1. Clindamycin 10 to 25 mg per kg divided every 8 hours AND
        2. Trimethoprim-Sulfamethoxazole (Bactrim, Septra) 8 to 10 mg/kg/day (trimethoprim component) divided twice daily
  4. Alternative Antibiotics for questionable compliance
    1. Ceftriaxone (Rocephin) IM qd

V. Management: Inpatient antibiotics

  1. Indications
    1. Systemic signs of infection (fever, chills...)
    2. Lymphangitis or Lymphadenitis
    3. Rapidly spreading Cellulitis
    4. Advancement of Cellulitis past one joint
    5. Tenosynovitis
    6. Septic Arthritis
    7. Osteomyelitis
    8. Nerve involvement
  2. Intravenous Antibiotics for severe cases
    1. Nafcillin (with or without Gentamicin)
    2. Timentin
    3. Second generation Cephalosporin
    4. Third generation Cephalosporin
  3. Consultations to consider
    1. General Surgery
    2. Orthopedics
    3. Plastic surgery

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Ontology: infected dog bite (C0850850)

Concepts Disease or Syndrome (T047)
English Infection;bite;dog, bite dog infection, bite dog infections, bites dog infections, infected dog bite