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Multisystems II > Microbiology-Bites > Flashcards

Flashcards in Microbiology-Bites Deck (27)
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1
Q

Most common cause of animal bites

A

Dogs

2
Q

Animal bites with higher risk of infection than dog bites

A

Cats, deeper penetration w/deeper infection and osteomyelitis

3
Q

Common microbial infections associated with cat and dog bites

A

Pasteurella, capnocytophagia, normal skin flora and anaerobes

4
Q

What people are at higher risk for infection by capnocytophagia after a dog/cat bite? What symptoms are common? How do you treat?

A

Immunocompromised. Presents with fever, muscle aches and rare sepsis. Tx with augmentin, avoid bactrim and aminoglycosides.

5
Q

Symptoms that commonly present with pasteurella infection after a cat/dog bite? How do you treat?

A

Fever, cellulitis, arthritis, pneumonia, endocarditis, meningitis 15 hours after bite. Tx with augmentin or azithromycin. Avoid erythromycin and clindamycin.

6
Q

More common microbe involved in community acquired MRSA from animals

A

S. intermedius > S. aureus.

7
Q

Indications for antibiotic prophylaxis after bits

A

Deep bites (cats), crush injuries, venous/lymphatic compromise, wounds close to bone, wounds that requires surgical care, immunocompromised. Drug of choice = augmentin.

8
Q

28 year old pregnant woman presents with a red and swollen cat bite. She has a penicillin allergy. What is appropriate empiric therapy?

A

Axithromycin

9
Q

Cat-scratch disease

A

Bartonella henselae (mostly in fall/winter in outdoor cats and affects younger kids)

10
Q

Cat scratch symptoms

A

Papule/pustule at site of infection, fever, enlarged lymph nodes 1-3 weeks after exposure.

11
Q

Diagnosing and treating cat-scratch disease.

A

Dx clinically most of the time, can also use serology or PCR. Tx with azithromycin if symptoms do not resolve spontaneously (they usually do).

12
Q

Common pathogens associated with human bites

A

Staph, strep, eikenella (facultative). Also worry about HSV, HIV, HepC and HepB.

13
Q

A 52 year old man suffers a hand injury in a brawl from punching a guy in the face. He has bony fragments on x-ray. He was given cephalexin in the ER and sent home. 5 days later he returns tachycardic, hypotensive, feverish and confused. His hand is warm, edematous, painful to move and has decreased sensation. He was given Tdap shot, started on amp-sulbactam and has a fasciotomy for compartment syndrome. Gram stain shows an anaerobic gram negative bacilli. How do you treat him?

A

Eikenella corrodens is a common infection in human “bites”. It is resistant to cephalexin, clindamycin, erythromycin and metronidazole. Tx with augmentin, fluoroquinolones, TMP-SMX or doxycycline.

14
Q

Common pathogens in pig bites? How do you treat them?

A

Strep, staph, pasteurella, actinobacillus, tx with augmentin + ciprofloxacin to cover actinobacillus.

15
Q

Symptoms and pathogens associated with rat-bite fever?

A

Streptobacillus moniliformis (US, branching gram-negative bacillus shown below), spirillum minus (asia). Symptoms: fever, pustular rash (shown below), migratory polyarthritis and endocarditis. Tx with augmentin or doxycycline.

16
Q

Pathogen associated with seal finger? Symptoms? Treatment?

A

Mycoplasma. Papular lesion with pain, swelling and joint involvement. Tx with tetracycline.

17
Q

Pathogens associated with the candiru fish (cat fish in amazon river attracted to urea)?

A

They swim up your urethra and lodge there to get urea waste.

18
Q

Bacterial infections associated with snake bites

A

Secondary flora wounds are rare because venom is sterile.

19
Q

Things to not do when bit by a snake? What should you do?

A

Suck out the venom, apply a tourniquet, place ice packs. You should give anti-venom, first aid and ceftriaxone + clavulanate empirically.

20
Q

Pathogens associated with monkey bites

A

Staph, strep, eikenella, Herpes B virus

21
Q

Symptoms associated with herpes B virus after a monkey bite?

A

Reactivation, vesicular lesions, paresthesias, seizures, respiratory failure. (80% fatality rate)

22
Q

Tx for person exposed to herpes B virus after a monkey bite

A

Prophylactic acyclovir if pregnant, valacyclovir for others (can be life-long). IV if CNS involved.

23
Q

3 phases of rabies

A

1) Flu-like illness, prickling at bite site 2) Agitation, delirium 3) Coma death

24
Q

Diagnosing rabies

A

1) Salive PCR 2) Neck biopsy (nerves) 3) Serum immunoassay 4) CSF immunoassay

25
Q

Animal bites that merit immediate rabies prophylaxis

A

Skunks, raccoons, foxes and bats. Give RIG if not previously vaccinated. Revaccinate if previously vaccinated, don’t give RIG if previously vaccinated.

26
Q

Path of infection by clostridium tetani?

A

Spores enter wound, germinate and make toxin that causes muscular spasms and seizures.

27
Q

Tx for tetanus

A

TIG, toxoid booster, antibiotics (penicillins or metronidazole). Give prophylaxis TIG and toxoid vaccine if immunization hx is unclear. Don’t give TIG if immunizations are clear and current.