Bites & the MCC
• According to the MCC, what are the bites that every doctor should know something about?
Important Medical Bites
MCC List:
1. Dog bites
2. Cat bites
3. Human bites
4. Insect stings
5. Snake bites
• Other list:
1. Spider bites
2. Jellyfish stings
3. Scorpion stings
4. Tick bites
5. Bat bites
Case 1
• A 20 woman presents with this bite• Delivering fliers• Neighbourhood dog• Unsure of owner• 12 hours ago
Case 1
1. Diagnostic issues?
2. Management issues?
3. Plan for this case?
4. Epidemiology?
5. Medicolegal?
Dog Bites
• Many MD visits (12,000 bites/day US)• Usually child <5• 10-20 deaths per year US• Dx Issues:
– 6 incisors, straight, large deep punctures– Circumstances; dog ownership; safety– Nature of each wound– r/o rabies– Bacteria: anaerobes, Strep, Staph, etc
• 5-6% dog bites get infected• Rare sepsis: Capnocytophaga canimorus
Dog Bites • Tx issues:
– Abx: Clavulin; Clinda + Cipro– Tetanus– Wound management – ?Closure– Pain management– Rabies prophylaxis– Public health reporting– Safety for all
• Medicolegal– Documentation– Testimony
Case 1 – Your Management?
• A 20 woman presents with this bite• Delivering fliers• Neighbourhood dog• Unsure of owner• 12 hours ago
Case 2
• 75 F• Her cat startled watching Senators loss on CBC• Bit her forearm• 3 hours ago• Pain worse • What should she do?
Cat Bites
1. Diagnostic issues?
2. Management issues?
3. Plan for this case?
4. Epidemiology?
5. Medicolegal?
Cat Bites• Similar to dog bites• 60-80% infection rate• Bacteria: esp Pasturella multocida• Very rapid cellulitis• Cat-scratch LN: Bartonella
• Rx Clavulin or Doxycyline• Splint• Re-check
Case 2 – Your Plan?
• 75 F• Her cat startled watching Senators loss on CBC• Bit her forearm• 3 hours ago• Pain worse • What should she do?
Case 3
• 19 male, HBD• “Minding his own business” at a bar• Assaulted• He “won”• Punched in face• Punched the other guy – cut his knuckle on tooth• Feeling hung over• Wants to leave
Human Bites• Bacterial Infections
– mouth bugs, including anaerobes, Staph, Strep– Eikenella– Rx Clavulin; Pip-tazo– Tetanus
• Viral infections– HIV, Hep B, Hep C; HSV– PEP
• Wound management• “Closed fist injuries” / “Fight bites”• Other sites: ears, etc• Four incisors, oval
Case 3 – What is Your Plan?
• 19 male, HBD• “Minding his own business” at a bar• Assaulted• He “won”• Punched in face• Punched the other guy – cut his knuckle on tooth• Feeling hung over• Wants to leave
Case 4 continued• Hymenoptera (honeybees, bumblebees, wasps, ants)
– Anaphylaxis (IgE, non)– Remove stinger– 2’ infections (Staph, Strep)
• Tick bites– Ixodes Lyme disease (Borrelia burgdorferi)– RMSF, Ehrichiosis, babesiosis, tularemia, etc– Rx Doxycycline
• Mosquito bites– Symptomatic (NSAIDS, antihistamines)– West Nile Virus
Case 4 continued - Spiders
• Black widow spider– Aggressive females– Rare systemic– Rx antivenom if severe
• Brown Recluse / “Fiddleback”– More common– Necrotic arachnism– DIC, death– Supportive
Case 5 – Snake Bites
• Wound care• Identify snake• In Canada: Massasauga rattler
• Antivenom (Rx CroFab)
That Bites! - Summary
• Clear history of events, timing• Identify all wounds• Wound care• Punctures • Foreign bodies• Tetanus• Abx• Other PEP: HIV, Hep B, Hep C, Rabies• Public health• Documentation
That Bites! - Summary
MCC List:
1. Dog bites
2. Cat bites
3. Human bites
4. Insect stings1. Hymenoptera
2. Mosquitoes
5. Snake bites
• Other list:
1. Spider bites1. Black widow
2. Brown recluse
2. Tick bites1. Lyme disease