Animal bites

Question 1

<8 hrs of bite, how do you treat a bite?

8-12 hrs of bite: how do you treat a bite?

Answer 1

<8 hrs: wound care, tetanus toxoid

8-12 hrs: infection

Question 2

Cat bites: what do you worry about? Compared to dogs?

Answer 2

Cats have narrow sharper teeth leading to deeper puncture wounds: thus higher risk of infection (osteomyelitis), soft tissue abscess.

cat bites is less destructive and life threatening than dog bites: dog bites is more crush tear injury severe bleeding open skull fractures

Question 3

What are common pathogens in dog/cat bite wound infections?

Answer 3

PASTURELLA
capnocytophagia canimorsus
anaerobes: bacteroides,
our own skin flora: staphylococci, streptococci

Question 4

Capnocytophaga canimorsus: symptoms of infection? resistant to what abx?

Answer 4

wide spectrum of infection - fever, myalgias, rash, go complaints, myocardiditis, endocarditis, meningitis. Bacteremia/sepsis is rare.

Resistant to TMX/SMX and aminoglycosides

Question 5

Pasteurella multocida: where is it carried? common symptoms? treatment? resistance?

Answer 5

Carried in nasopharynx of most cats. local cellulitis, low grade fevers => abscess, septic arthritis, pneumonia, endocarditis, meningitis

Tx: b-lactams, azithromycin
AVOID erythromycin, CLINDAMYCIN

Question 6

community acquired MRSA:

Answer 6

S. intermedius > s. aureus

dermatitis, pustular disease, perineal cellulitis

Question 7

wound management:

Answer 7

irrigation (sterile saline), debridement
surgery
leave wound open (delay closure - except for facial wounds)
elevate
antibiotics

Question 8

drug of choice for cat/dog bites

Answer 8

ORAL: amoxicillin-clavulanate
doxycycline/TMP-SMX/penicillin/cefuroxime + metronidazole/clindamycin

AVOID: cephalexin, dicloxacillin, erythromycin

IV: b-lactam/b-lactamase inhibitors (ampicillin-sublactam)
ceftriaxone + metronidazole

Question 9

28 yo pregnant female (34 wks) presents with erythematous and swollen right hand following a cat bite

Answer 9

d) Azithromycin

doxycycline, TMX/SMX and metronidazole is contraindicated in pregnancy

Clindamycin does not cover P. multocida.

Question 10

Human bites: what bug? what viruses? How to treat?

Answer 10

more serious
normal flora: strep, staph, anaerobes
- EIKENELLA CORRODENS
potential transmission: herpes, HBV, HCV, HIV

Tx: Amoxicillin-clavulanate and moxifloacin is best
drugs for cat/dog bites also work here too.
AVOID: cephalexin, dicloxacillin, macrolides, clindamycin, aminoglycosides

Question 11

Bartonella henselae: what disease does it cause?

Answer 11

cat scratch disease - papule/pustule at inoculation site. fever, enlarged tender lymph nodes that develop in 1-3 wks after exposure.

rare: eye infection, severe myositis, encephalitis, endocarditis

Question 12

cat scratch disease: bartonella henselae: diagnosis and treatment

Answer 12

Dx: clinical, serology, PCR/culture
Tx: most cases resolve spontaneously.
Azithromycin (Z-pack) for disseminated or severe disease.

Question 13

Boar/pig bites: main bug?

Answer 13

actinobacillus suis
strep/staph/p. multocida, anaerobes

Tx: amoxicillin-clavulanate +/- ciprofloxacin

Question 14

Rat bite: main bug?

Answer 14

Streptobacillus moniliformis
spirillum minus
symptoms: fever, rash, migratory polyarthralgias
complication: endocarditis

Tx: Amox-clav, doxycycline

Question 15

Seal bite: main bug?

Answer 15

Causes seal finger!

mycoplasma (M. phocidae, M. salivarium)
papular lesion => pain, swelling, joint involvement

Tx: tetracyclines x4 weeks

Question 16

Candiru

Answer 16

fish of amazon - enters mans urethra

Question 17

snake bites: how do you NOT treat? What abx do you give?

Answer 17

do NO make local incisions, suck the venom out, tourniquet extremity, place ice packs

empiric antibiotics: ceftriaxone, B-lactamase inhibitors

Question 18

Monkey bites: common bugs. how do you treat the virus?

Answer 18

strep, staph, eiknella, anaerobes

HERPES B VIRUS (especially among macaque monkeys)- tx with valacyclovir

Question 19

Rabies: describe clinical presentation

Answer 19

phase 1: flue-like, discomfort, prickling/pruritic sensation at bite site

phase 2: anxiety, confusion, delirium, abnormal behavior, hallucination, insomnia, hydrophobia

phase 3: coma, death

Question 20

Rabies dx

Answer 20

4 sample sites: test for RT-PCR, ab with indirect IF, virus isolation in these locations:
1. saliva
2. neck punch biopsy
3. serum
4 csf

Question 21

5 rules on how to deal with rabies

Answer 21

1. understand disease (know region - rabies is often regional)
2. avoid getting bit
3. low threshold for PEP
4. if Bit - clean wound aggressively, post-exposure prophylaxis
5. follow rules ASAP - do NOT delay

Question 22

Tetanus: that is the bug? where is it found, and how does it work?

Answer 22

clostridium tetani

• environmental: found in soil, dust, manure
• spores enter via wound or breach in skin: disseminated toxin in CNS interfere with neurotransmitter release => unopposed muscle contraction, spasm

Question 23

treatment for tetanus

Answer 23

• tetanus immune globulin
• tetanus toxoid booster
• aggressive wound care
• antibiotics
• mechanical ventilation
• sedation
• muscle relaxants