When Animals Bite

Question 1

infection is likely after how many hours?

Answer 1

8

Question 2

risk factors for biting dogs

Answer 2

terrier/herding breeds, pitbulls, rottwiler, german shepherds

sexually intact male dogs

purebred

low income neighborhoods

aggressive kids/owners

Question 3

cat bites

Answer 3

less destructive but higher risk of infection (deeper puncture)

progress more rapidly to infection/abcess

more freq upper extremities

Question 4

manifestations of cat bite v dog bite

Answer 4

cat - hands/upper extremities; deep abscess or osteomyelitis

dog - depressed/open skull fractures, severe scalp and intracranial bleeding; trauma

Question 5

cat bite aerobes vs dog bite aerobes

Answer 5

cat = pasteurella, strep, staph, and moraxella

dog = pasteurella, strep, staph, and neisseria

Question 6

cat bit anaerobes vs dog bite anaerobes

Answer 6

cat = fusobacterium, bacteriodes, porphyromonas

dog = fusobacterium, bacteriodes, porphyromonas, prevotella, and capnocytophagia

Question 7

capnocytophagia

Answer 7

G-

anaerobe in dog bites

can cause sepsis in asplenic/immunocompromised people –> treat dog bite with cephalosporin

Question 8

if a person presents with cat bite with penicillin allergy you treat with

Answer 8

metronidazole + ciprofloxacin

fluoroquinolones cover pasteurella (cipro)

Question 9

pasteurella

Answer 9

nasopharynx of cats

15 hr incubation

local cellulitis and low grade fever can lead to absess, septic arthritis, osteomyelitis, pneumonia, endocarditis, and meningitis

sensitive to amox-clav (drug of choice is B-lactam + inhibitor), azithromycin

DOES NOT respond to erythromycin or clindamycin

Question 10

capnocytophaga canimorsus

Answer 10

in dog bites

Severe infection in immunocompromised

treat w 3rd gen ceph

Question 11

first part of care management

Answer 11

aggressive cleaning/irrigation!!

cleaning + elevate + antibiotics

Question 12

oral abx drug of choice for dog bite

Answer 12

amoxicillin-clavulanate

Question 13

clindamycin doesnt cover against

Answer 13

pasteurella

Question 14

cat scratch disease

Answer 14

caused by bartonella henselae after a bite or scratch from a cat –> papule/pustule develops, fever, and enlarged tender LNs 1-3 weeks after

kids in fall/winter

rarely progresses to complications

Question 15

Answer 15

cat scratch disease

bartonella henselae

Question 16

treatment for cat scratch disease?

Answer 16

Z pack - azithromycin

Question 17

treatment for human bites

Answer 17

amoxicillin-clavulanate

Question 18

eikenella corrodens

Answer 18

anaerobic Gram neg. bacilli

common in human bites

resistant to: cephalexin, clindamycin, erythromycin, and metronidazole

sensitive to: penicillins (amox-clav), fluoroquinolones, tmp/smx, doxycycline

Question 19

big cats bite

Answer 19

pasteurella present

rapid onset cellulitis –> deep structure involvement

Question 20

acinetobacter baumanii

Answer 20

environmental pathogen; seen in wounded warriers overseas

gram - bacillus

treat with amox-sulbactam and colistin

Question 21

rat bite fever

Answer 21

caused by streptobacillus moniliformis or spirillum minus

branching gram neg bacilli that causes pustular rash

risks: kids, pet shops, poor areas, labs
symptoms: relapsing fever, rash, migratory polyarthralgias –> can lead to endocarditis

treat with a penicillin (amox-clav) or doxycycline

Question 22

mycobacterium marinum

Answer 22

fresh and salt water tanks or pools

granuloma from a minor injury or abrasion with cleaning fish tank

causes cutaneous lesions: soft papules, pustules, and ulcers weeks afterwards

Question 23

vibrio vulnificus

Answer 23

due to shellfish or saltwater/brackish water

**filter feeding fish concentrate the bacteria

severe disease in people with liver disease, hemochromatosis, or alcohol abuse

treat with doxy + ceftriaxone

Question 24

snake bites

Answer 24

**bacterial infections are rare since venom is sterile

when treating, DO NOT make local incision, suck the venom out, tourniquet the extremity, or place ice packs

Question 25

treatment for snake bites

Answer 25

ceftriaxone and B-lactamase inhibitors as empiric abx

Question 26

monkey bites can carry…

Answer 26

herpes B virus

Question 27

herpes B virus from monkey

Answer 27

• Endemic among macaque monkeys
• Persists in sensory ganglia for lifetime, reactivates
• Incubation 5-21 days
• Vesicular lesion, paresthesias –> Seizures, ascending paralysis, respiratory failure

treat w valacyclovir or use acyclovir if woman is pregnant

Question 28

rabies 3 phases

Answer 28

• 1st phase: Flu-like illness; Discomfort, prickling/pruritic sensation at bite
• 2nd phase: anxiety, confusion, agitation; insomnia, hydrophobia
• 3rd phase: Coma, death

Question 29

tetanus

Answer 29

• pathogen is Clostridium tetani
• Environmental pathogen: soil, dust, manure

Spores enter via wound or breach in skin –> Disseminate toxin that acts within CNS

–Toxin interferes with neurotransmitter release, blocking inhibitor impulses

–Unopposed muscle contraction, spasm

presents as painful muscular contractions (lock jaw) and rigidity, spasms, and seizures

treatment = tetanus immune globulin (TIG), tetanus toxoid booster, relaxant to control muscles, and abx

Question 30

if suspect pasteurella species as infection, do not

Answer 30

treat with clindmycin alone!