Bacillus

Question 1

Bacillus descriptive statement

Answer 1

LARGE Gram + rods -Motile(most) - Catalase +, Oxidase -, Aerobes/facultative anaerobes- Endospores (persist in environment 50+ yrs)

Question 2

Bacillus anthracis Transmission

Answer 2

Ingestion/inhalation/ invasion of wounds by spores–> complex toxins

Question 3

Bacillus anthracis Virulence Factors

Answer 3

Capsule w/ poly D glutamic acid - Protective antigen - Edema factor (EdTx or EF) - Lethal Factor (LeTx or LF)

Question 4

Bacillus anthracis Edema factor effects

Answer 4

Adenylate cyclase upsets water homeostasis

Question 5

Bacillus anthracis Protective antigen

Answer 5

Binds EF and LF - Essential for those factors to function - (PA+LF=Lethal Activity) (EF+PA=edema) (EF+LF=inactive) (PA+LF+EF=edema & necrosis, lethal)

Question 6

Bacillus anthracis Lethal factor

Answer 6

Zinc metalloprotease, essential for lethal effects

Question 7

Bacillus anthracis aka…

Answer 7

Anthrax!! Category A bioterrorism agent!

Question 8

Bacillus anthracis colonies

Answer 8

“Ground Glass” - “Medusa Head colony”

Question 9

When I say medusa head colony, you say…

Answer 9

B. anthracis!

Question 10

Bacillus anthracis susceptibility

Answer 10

Ruminants > Carnivores > birds=resistant

Question 11

What should you do if you find a big, dead, bloated cow with no signs of rigor mortis?

Answer 11

NOT NECROPSY! Report it, get authorities to do it properly or on-site incineration

Question 12

Bacillus anthracis: Ruminants (including post mortem description)

Answer 12

Septicemia, rapidly fatal. Epistaxis - Postmortem: rapid bloating, incomplete rigor, widespread hemorrhages, edema, large soft spleen

Question 13

Bacillus anthracis in Pigs

Answer 13

Less fatal (similar in carnivores) - Edema of throat & head - Mesenteric & regional lymphadenitis - Dysentary (Swollen head, bloody diarrhea)

Question 14

Bacillus anthracis in horses

Answer 14

SQ edema of thorax, abdomen, legs - Swelling of pharynx, asphyxiation - In septicemic cases, extensive ecchymoses and splenomegaly (Swollen trunk / pharynx / legs)

Question 15

If I say edematous swelling of throat & head of a pig or carnivore, you say…

Answer 15

Bacillus anthracis!

Question 16

If I say SubQ edema of thorax, abdomen or legs of a horse, you might say….

Answer 16

Bacillus anthracis!

Question 17

If I say multifocal, hemorrhagic enteric lesions, you say…

Answer 17

Dysentery!

Question 18

If I say extensive ecchymoses and splenomegaly in a horse, you might say

Answer 18

Bacillus anthracis - septicemic case!

Question 19

Bacillus anthracis in humans

Answer 19

Cutaneous anthrax (most common) - Inhalation anthrax (“Wool sorters’ disease) - GI anthrax

Question 20

If I say Wool Sorters’ disease, you say….

Answer 20

Bacillus anthracis in humans!

Question 21

What does Bacillus lichemiformis cause, in what species?

Answer 21

Sporadic abortion in cattle & sheep

Question 22

Bacillus cereus

Answer 22

“Be serious” - Human food poisoning - Rare mastitis in cows

Question 23

Bacillus larvae

Answer 23

American foulbrood in bees

Question 24

What does a HIGH dose of LeTx or LF cause?

Answer 24

Apoptosis of macrophages

Question 25

What does a LOW dose of LeTx or LF cause?

Answer 25

Cytokine “storm” –> multiorgan dysfunction - endotoxemia

Question 26

Bacillus antracis pathogenesis

Answer 26

Spores in environment –> Macrophages phago. –> AtxA or AcpA trigger “activation” of bacteria –> release LeTx and EdTx, capsule, other toxins –> Escape –> hyperproduction of cytokines –> gelatinous edema & bleeding from EVERYWHERE

Question 27

Bacillus anthracis Post-mortem

Answer 27

Widespread hemorrhages - Black,engorged, friable spleen - Tarry, non-clotting blood - Absence of rigor