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Flashcards in Invasive Clostridia Deck (42)
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1

Invasive clostridia - Description

Gram + *Spore forming, Anaerobic rods - *Fermentative - Catalase & oxidase negative - *Motile (peritricous flagella like Listeria, C. perfringens nonmotile) - CAMP positive with S. agalactiae

2

What is the most frequently isolated pathogenic bacterium of Gas gangrene, Endotoxemias & Diarrhea in ruminants?

C. perfringens

3

Invasive C. perfringens toxins

Alpha - Beta - Epsilon - Iota - Perfringolysin O - Enterotoxin

4

Alpha toxin

Hemolysis, necrosis, lethality *Especially C. perfringens*

5

Beta toxin

Pore-forming (inhibited by colostrum trypsin inhibitors)

6

Epsilon toxin

Necrotizing & lethal - brain and kidney - activated by trypsin

7

Iota toxin

Cellular cytoskeleton & death of affected cell

8

Perfringolysin O

Cholesterol-binding, escape from phagolysosome

9

Enterotoxin

Fluid & electrolyte abnormalities

10

C. perfringens disease patterns - Wound infection

Type A - alpha toxin - anaerobic Cellulitis & gas gangrene - Myonecrosis w/edema, hemorrhage, emphysema fatal toxemia - OFTEN from needle sharing between equines

11

C. perfringens disease patterns - Enterotoxiemias Type A

Tissue destruction - Yellow lamb dz - Hemorrhagic/Necrotic enteritis - Canine hemorrhagic gastroenteritis

12

Describe Yellow lamb disease

Gastritis and hemolytic disease caused by C. perfringens

13

C. perfringens disease patterns - Enterotoxemias Type B

Old world diseases - Lamb Dysentary - B toxin (trypsin-susceptible) - Rapidly fatal, 100% mortality

14

C. perfringens disease patterns - Enterotoxemias Type C

NEONATAL hemorrhagic enteritis (calves, foals, piglets, lambs) - B toxin virulence! - "Stuck" in older sheep (looks like was "struck by lightening")

15

C. perfringens disease patterns - Enterotoxemia Type D

Older animals - Epsilon toxin! - Overeating dz - Pulpy kidney dz

16

When I say OverEating dz or Pulpy kidney dz, you say...

Enterotoxemia Type D! Invasive C. perfringens!

17

Clostridia disease patterns - Enterotoxigenic diarrhea

Enterotoxin CpE --> sporulation - Watery to hemorrhagic diarrhea - VERY common food-related dz in humans

18

Clostridium difficile - Pathogenesis

Enterotoxin - Toxin A - Trigger event--> disrupt normal flora & colonize --> adhere to large intestine --> toxin production --> intense inflammatory response --> diarrhea

19

Clostridium novyi - Type 1 infections & toxins

Alpha & Delta toxin (Novyilysin) - Gas gangrene - Big head (fight injury in rams, toxic endothelial damage--> edema)

20

When I say Big head in rams, you say

C. novyi type 1

21

C. novyi Type 2 infections & toxins

Alpha & Beta toxins - Black disease (pericardial edema) - Iron Chocolate Liver

22

C. novyi Type 2 pathogenesis

Spores mobilized, intestine--> liver --> dormant in Kupffer cells --> hepatocytes damaged from fluke migration!!!!!!--> spores germinate --> B toxin production & dissemination --> sudden death

23

C. novyi Type 2 pathogenesis - Secondary effects/signs

SQ venous congestion secondary to pericardial edema - Gas bubbles in the liver

24

When you see gas bubbles in the liver, you think

C. novyi type 2!!

25

Black Disease or Iron Chocolate Liver

C. novyi type 2!!

26

C. novyi Prevention/Tx?

Prevent flukes!! no fluke, no liver damage, no release of toxin

27

Clostridium haemolyticum

Resembles C. novyi type 2 - Phospholipase C and Beta toxin virulence factor!! - Hemolytic crisis & acute death - Bacillary hemoglobinuria or "red water" disease of ruminants

28

When I say "red water diseases" of ruminants, you say...

C. haemolyticum!

29

Clostridium septicum general info

Leading cause of farm animal wound infestation - Malignant Edema - Braxy or bradsot - Alpha toxin*** - Spores maybe latent in muscle - Guarded prognosis

30

Clostridium septicum - Malignant edema pathogenesis

Direct contamination --> hemorrhage, edema, necrosis --> painful,warm, pitting lesions --> becomes cold, crepitant, loses feeling --> death