Bioterrorism

Question 1

influenza-like illness

cough and severe SOB ~48hrs later

Chest imaging w/: widened mediastinum

Answer 1

think inhalational anthrax

widened MS = LN dissemination and hemorrhagic mediastinitis

(lung parenchyma may be normal)

Question 2

itchy raised lesion → papule → vesicle

prominent edema

black eschar over few days

swelling often disproportionate to size of skin lesion itself

painless

Answer 2

consider cutaneous anthrax

Question 3

Dx of anthrax

Answer 3

• can be cultured on standard media = GP nonmotile, spore-forming rods​
• PCR
• convalescent sera (4-fold rise)
• skin bx for histo/PCR

Question 4

Answer 4

GP nonmotile rods in chains (spore-forming)

anthrax

Question 5

Tx of anthrax

Answer 5

• systemic or meningitis: quinolone + b-lactam + protein synthesis inhibitor (eg cipro + mero + linezolid) x3 wks
  
  • Due to B-lactam R variability and needing good CNS penetration
  • B-lactam can be dc if meningitis r/o
  • • anthrax Ig or antitoxin if inhalation/systemic
      
      • counteract extracellular toxins
• cutaneous alone: cipro or doxy x60 days

Question 6

severe, progressive, symmetrical, CN signs (diplopia, ptosis, facial weakness → dysphagia, dysphonia)

progressives to descending flaccid paralysis, respiratory failure, autonomic instability

Answer 6

consider botulism

Question 7

Answer 7

C botulinum

large GP bacilli w/ terminal spores

Question 8

fevers, sweats, malaise, HA → progressive SOB, bloody sputum, chest pain

Answer 8

consider pneumonic plague (Y pestis, likely inhalation)

this, and bubonic plague, are contagious and require contact/airborne precautions

Question 9

fat, GN bacilli w/ bipolar staining (“safety-pin” appearance on older cx)

will grow on blood or broth media

slow-growing (not fastidious)

Blood agar colonies: small, grey/white/yellow color w/ irregular surface

Answer 9

yersinia pestis (plague)

Question 10

tx of yersinia pestis

Answer 10

IV gent + IV cipro x2wk minimum

(PO cipro if mild or as stepdown)

Question 11

Clinical presentation of smallpox

Answer 11

(in order)

1. Initial short prodome (~3D) w/ abrupt fever, severe myalgias, HA, malaise, vomiting
2. followed by development of mouth sores
3. rash affecting face → trunk → extremities (centrifugal)
   
   1. widespread erythema → maculopapular → vesicular → pustular
   2. characteristic: deep, tense well-circumscribed pustules that scab then heal in 10 days
   3. same stage of development

Question 12

dx of smallpox

Answer 12

vesicular fluid and viral throat swabs for NAAT

Question 13

ulcerative necrosis of tracheobronchial tree w/ regional (neck/MS) LAD

Answer 13

consider glanders (B mallei)

can also have PNA, lung abscesses, effusions, or pulm miliary infection

bacteremia can occur (multiple dissem abscesses)

cx on standard media. may be misidentified as PSAR