Gastrointestinal Infections III (22) Flashcards
What are characteristics of campylobacter jejuni?
gram-negative
gull-winged shape
How does c. jejuni spread?
fecal-oral
adhesins
produces cytotoxins - cytolethal distending toxin (CDT)
What is disease severity for c. jejuni is classified how?
What are clinical signs of c. jejuni?
hemorrhagic enterocolitis
How do you diagnose c. jejuni?
rapid presumptive diagnosis - direct microscopic examination of feces using wet mount
- dark-field microscopy (darting motility)
fecal culture: requires microaerophilic conditions
How do you treat c. jejuni?
efficacy of antibiotics in dogs and cats not known
- erythromycin is drug of choice
What are the general characteristics of clostridium species?
gram-positive rods
obligate anaerobes
What does clostridium spp. form and produce?
form: spores
produce: exotoxins
What is the causative agent of clostridial diarrhea?
clostridium perfringens
Clostridium perfringens is divided into five different types:
A
B
C
D
E
All clostridium perfringens are ____
exotoxins
immunologically distinct
have necrotizing and lethal actions
host and geographic association
What are predisposing factors to enterotoxemia?
spores
management factors: high energy diet
drugs that reduce peristalsis
disruption of normal flora
What is the causative agent for hemorrhagic enterotoxemia?
c. perfringens type C
What is hemorrhagic enterotoxemia?
c. perfringens type C
affects neonates
produces alpha and beta toxin
Why are neonates susceptible to hemorrhagic enterotoxemia?
intestinal trypsin inactivates beta toxin
neonates: have low trypsin in intestine
What is the encounter of clostridium perfringens?
present in soil and intestinal tract of healthy animals
- passed in feces
- normal flora
How does clostridium perfringens enter the body?
feco-oral route
How does clostridium perfringens damage the body - hemorrhagic enterotoxemia?
damages microvilli and cells
efflux of leukocytes, RBCs platelets
damages leukocytes, platelets, RBCs
What are clinical signs of hemorrhagic enterotoxemia?
What is the CONFIRMATORY diagnosis for clostridium perfringens - hemorrhagic enteritoxemia?
toxin neutralization test
What are often unrewarding treatments for hemorrhagic enterotoxemia?
How do you prevent hemorrhagic enterotoxemia?
vaccinate dams with toxoid
ensure adequate colostrum intake
How does clostridium difficile cause damage?
produces 2 toxins
toxin A: enterotoxin
toxin b: cytotoxin
Regarding clostridium dificile, toxin A is a ____ which causes _____, and toxin B is a _____ which causes ________
A: enterotoxin, causes fluid secretion
B: cytotoxin, results in epithelial necrosis
What is the gold standard for diagnosing clostridium difficile?
demonstrate toxins in fecal sample
Is there a vaccine for CDAD?
NO
What is the causative agent of necrotic enteritis?
clostridium perfringens type A
What diseases does clostridium perfringens type A cause?
necrotic enteritis
enterotozaemia
neonatal diarrhea in calves
What does clostridium perfringens type B cause?
lamb dystentery
What does clostridium perfringens type D cause?
enterotoxemia in older feedlot lambs
aka overeating disease
