Flashcards in Invasive Clostridia Deck (42)
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
What is the most frequently isolated pathogenic bacterium of Gas gangrene, Endotoxemias & Diarrhea in ruminants?
Invasive C. perfringens toxins
Alpha - Beta - Epsilon - Iota - Perfringolysin O - Enterotoxin
Hemolysis, necrosis, lethality *Especially C. perfringens*
Pore-forming (inhibited by colostrum trypsin inhibitors)
Necrotizing & lethal - brain and kidney - activated by trypsin
Cellular cytoskeleton & death of affected cell
Cholesterol-binding, escape from phagolysosome
Fluid & electrolyte abnormalities
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
C. perfringens disease patterns - Enterotoxiemias Type A
Tissue destruction - Yellow lamb dz - Hemorrhagic/Necrotic enteritis - Canine hemorrhagic gastroenteritis
Describe Yellow lamb disease
Gastritis and hemolytic disease caused by C. perfringens
C. perfringens disease patterns - Enterotoxemias Type B
Old world diseases - Lamb Dysentary - B toxin (trypsin-susceptible) - Rapidly fatal, 100% mortality
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")
C. perfringens disease patterns - Enterotoxemia Type D
Older animals - Epsilon toxin! - Overeating dz - Pulpy kidney dz
When I say OverEating dz or Pulpy kidney dz, you say...
Enterotoxemia Type D! Invasive C. perfringens!
Clostridia disease patterns - Enterotoxigenic diarrhea
Enterotoxin CpE --> sporulation - Watery to hemorrhagic diarrhea - VERY common food-related dz in humans
Clostridium difficile - Pathogenesis
Enterotoxin - Toxin A - Trigger event--> disrupt normal flora & colonize --> adhere to large intestine --> toxin production --> intense inflammatory response --> diarrhea
Clostridium novyi - Type 1 infections & toxins
Alpha & Delta toxin (Novyilysin) - Gas gangrene - Big head (fight injury in rams, toxic endothelial damage--> edema)
When I say Big head in rams, you say
C. novyi type 1
C. novyi Type 2 infections & toxins
Alpha & Beta toxins - Black disease (pericardial edema) - Iron Chocolate Liver
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
C. novyi Type 2 pathogenesis - Secondary effects/signs
SQ venous congestion secondary to pericardial edema - Gas bubbles in the liver
When you see gas bubbles in the liver, you think
C. novyi type 2!!
Black Disease or Iron Chocolate Liver
C. novyi type 2!!
C. novyi Prevention/Tx?
Prevent flukes!! no fluke, no liver damage, no release of toxin
Resembles C. novyi type 2 - Phospholipase C and Beta toxin virulence factor!! - Hemolytic crisis & acute death - Bacillary hemoglobinuria or "red water" disease of ruminants
When I say "red water diseases" of ruminants, you say...
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
Clostridium septicum - Malignant edema pathogenesis
Direct contamination --> hemorrhage, edema, necrosis --> painful,warm, pitting lesions --> becomes cold, crepitant, loses feeling --> death
When I say malignant edema, you say...
When I say bradsot or braxy, you say
Clostridium chauvoei - Main disease pattern
BLACK LEG!! - necrotizing myositis in cattle
When I say Black Leg, you say...
C. chauvoei general info
Endogenous, soil-acquired infection, ingestion or injury maybe too - Alpha toxin!! (hemolytic, necrotizing, lethal) - May resemble gas gangrene / malignant edema
C. chauvoei pathogenesis
Toxins & bacterial metabolism (fermentation gases) cause intitial lesion --> seeding of tissue (muscle) with spores from intestine --> edema, hemorrhage, myofibrillar necrosis
Tyzzer's disease - acute fatal diarrheal disease in foals, rabbits, lab mice etc
When I say Tyzzer's disease, you say...
Fatal myositis & hepatic disease in ruminants and horses
Quail disease, ulcerative enteritis & necrotizing hepatitis
Juvenile enteritis in rabbits