Lecture 16 11/6/23 Flashcards
What are the general characteristics of Campylobacter spp.?
-curved, motile, gram-neg rods
-opportunistic extracellular
-microaerophilic
-do not survive in environment
-inhabit GI and lower genital tracts
-difficult to isolate; need special cultures
What are the characteristics of C. jejuni?
-cause of intestinal infection and diarrhea
-transmitted through ingestion of contaminated material
-common in young animals/poor conditions
What are the characteristics of C. jejuni virulence and pathogenesis?
-motility through single bipolar flagellum
-heat labile enterotoxin
What are the potential outcomes of C. jejuni disease?
-self-limiting, benign enteritis
-superficial erosive colitis and ileitis
-bacterial invasion/bacteremia
How is C. jejuni diagnosed??
-feces culture
-PCR
How is C. jejuni treated?
-no treatment for self-limiting disease
-macrolides/fluoroquinolones for severe cases
How can C. jejuni be prevented?
-food/kitchen hygiene
-adequate cooking times
-fly control
-slaughterhouse/processing hygiene
Which antibiotic is C. jejuni showing resistance to?
fluoroquinolones
What is the post-infectious syndrome associated with C. jejuni?
-Guillain-Barre syndrome
-acute immune-mediated demyelination of peripheral nerves
What are the two subspecies of C. fetus?
-subsp. venerealis
-subsp. fetus
What type of infection does C. fetus cause in bulls?
subclinical infection in preputial crypts (bovine venereal campylobacteriosis)
How can C. fetus be transmitted?
-venereal infection
-contaminated instruments, bedding, and semen
What are the characteristics of C. fetus clinical disease?
-breeding/insemination with infected semen/bull
-colonization of female genital tract
-infertility/repeat breeding
What conditions can cause transient fertility and early embryonic death?
-endometritis
-salpingitis
What is the route of infection for C. fetus subsp. fetus?
oral/ingestion
What happens to fetuses infected with C. fetus fetus?
-autolyzed
-orange-yellow necrotic foci in liver
How can C. fetus be diagnosed in bulls?
-detection in smegma, preputial wash, or semen
-darkfield microscopy
-PCR
-culture
What are the characteristics of PCR for diagnosing C. fetus in bulls?
-bact. can only survive for a few hours after collection
-inoculation in appropriate media can increase survival
How is C. fetus diagnosed in cows?
detection of IgA antibodies in cervical/vaginal mucus
How can C. fetus be treated?
-rare use of antimicrobials for intrauterine/preputial infusions
-more routine antimicrobial use for semen extenders
How can C. fetus be controlled?
-breed animals that test negative
-use young bulls
-vaccination
What are the characteristics of Vibrio cholerae?
-causes cholera, acute diarrheal illness through intestinal infection
-often mild
-rapid loss of body fluids can lead to dehydration/shock
-death can occur in hours
What are the characteristics of Helicobacter?
-small, spirally curved, gram-neg
-microaerophilic
-pathogenic and commensals of gastric mucosa and intestine
-causes gastric ulcers and gastric neoplasms
What are the virulence factors of Helicobacter pylori?
-adhesins
-flagella
-endotoxin
-extracellular urease
-mucinase
-vacuolating cytotoxin
-catalase
What is the most important virulence factor for H. pylori?
extracellular urease
Which Helicobacter species are found in the stomachs of dogs and cats?
-H. canis
-H. felis
-H. heilmannii
What are the characteristics of H. hepaticus and H. bilis?
-mouse pathogens
-cause hepatocellular tumors
What diseases are caused by H. mustelae in ferrets?
-hypergastrinemia
-peptic ulcers
How are Helicobacter sp. diagnosed?
-endoscopy/biopsy
-urease/breath test
-microscopic detection
-serology
-PCR
How are Helicobacter sp. treated?
-gastric proton pump inhibitors
-antimicrobials in humans
How can Helicobacter sp. be controlled?
-isolate/treat infected animals
-test and cull lab animals
What are the characteristics of Lawsonia intracellularis?
-small, spirally curved, gram-neg
-obligate intracellular
-replicate in apical cytoplasm of enterocytes
-cannot grow in a lab
Which disease is L. intracellularis associated with in swine?
associated with porcine proliferative enteropathy
What is the pathognomonic sign for L. intracellularis?
serosal cerebriform or gyrate pattern of projections/depressions in distal ileum/colon
Which disease is caused by L. intracellularis in horses?
equine proliferative enteropathy
How is L. intracellularis diagnosed?
-histopath and silver staining
-PCR
-serology
How is L. intracellularis treated?
-antimicrobials in feed/water
How is L. intracellularis controlled?
-live attenuated vx for swine
-intrarectal vx in horses
-specific pathogen free approaches
