When Animals Bite

Question 1

Most likely to be bitten by a dog

Answer 1

9 year old

Question 2

Most likely to be bitten by a cat

Answer 2

75 year old

Question 3

Most likely to have complications following a human bite

Answer 3

1 year old and 75 year old

Question 4

Risk of infections is highest among which of the following:

dog, cat, human

Answer 4

Risk of infection is greatest following a cat bite

cat > human > dog

Question 5

Cellulitis following a cat or dog bite

Answer 5

Pasteurella multocida

Question 6

Average 5 bacterial isolates following a cat/dog bite

Answer 6

Pasteurella

Strep

Staph

Neisseria

Fusobacterium/Bacteroides

Question 7

Gram - coccobacillus

Local cellulitis

Low grade fever

Answer 7

Pasteurella multocida

Other complications include:

Abscess, septic arthritis, osteomyelitis

Pneumonia, endocarditis, meningitis

Question 8

What is P. multocida inherently resistant to?

Answer 8

Clindamycin

(Also avoid erythromycin)

Question 9

Tx for P. multocida

Answer 9

B-lactam + suicide inhibitor

(Amoxicillin + Clavulanic acid)

Question 10

Tx for a pregnant woman following a dog/cat bite

Answer 10

Azithromycin

Question 11

Tx for someone with a penicillin allergy following a dog/cat bite

Answer 11

Metronidazole + Cipro

Question 12

Carried in the nasopharynx of 50-90% of cats

Answer 12

P. multocida

Question 13

Normal flora in dogs/cats

Answer 13

Capnocytophagia canimosus

• Gram - rod*
• Anaerobe*

Question 14

Complications of C. canimosus

Answer 14

Wide spectrum (fevers, myalgias, rash, etc.)

bacteremia/sepsis is very rare, but has a high mortality rate

Question 15

Tx of C. canimosus

Answer 15

Amoxicillin + Clavulanic Acid

AVOID: TMX/SMX and Aminoglycosides

Question 16

Lymphadenopathy following cat scratch

Answer 16

Bartonella henselae

Gram - rod w/ flagella

Give azithromycin for disseminated or severe disease

(most resolve spontaneously)

Question 17

Human bites

Answer 17

After looking for staph/strep…

Eikenella corrodens

Question 18

Anaerobic

Small G - bacilli

Bleach smell

Answer 18

Eikenella corrodens

Question 19

Tx of Eikenella corrodens

Answer 19

Resitant to many drugs (Cephalexin, Clindamycin, Erythromycin, and Metronidazole)

Susceptible to: penicillins, fluroquinolones, TMP/SMX, and doxy

Question 20

Tiger bite

Answer 20

P. multocida

(Big Cat)

Question 21

Pig Bite

Answer 21

Staph/Strep

Acintobacillus suis

Question 22

Rat Bite Fever

Answer 22

Streptobacillus moniliformis & spirillum minus

Gram - branching bacilli

Fever, rash, migratory polyarthralgias, endocarditis

Tx = PCN derivative or doxy

Question 23

Tx for a snake bite

Answer 23

Many bites are “dry” (i.e., no venom)

Ceftriaxone + B-lactamase inhibitors

Question 24

Fish tank granuloma

Answer 24

Mycobacterium marinum

Acid fast

Question 25

Candiru fish

Answer 25

Swim up urethra

Question 26

Bite from a macaque monkey

Answer 26

HBV is endemic among these monkeys

Incubation of 5-21 days, followed by vesicular lesion, paresthesias, seizures, ascending paralysis, and respiratory failure

Tx: wash wound for 15 minutes and give valacyclovir

Question 27

Tx for a pregnant woman following a monkey bite

Answer 27

Acyclovir

(Gancyclovir if CNS/PNS findings are found)

Question 28

Shellfish (raw oysters)

Answer 28

Vibrio vulnificus

Risk factors for severe disease = liver disease, hemochromatosis, alcohol abuse

Question 29

Work up for rabies

Answer 29

1. Saliva (PCR)
2. Neck biopsy (PCR and IF)
3. Serum (Ab)
4. CSF (Ab)

Question 30

MRSA following animal bite

Answer 30

S. intermedius is more common than S. aureus

Question 31

Common infection during OEF/OIF

Answer 31

Acinetobacter baumanii