Flashcards in Micro: H. Pylori, Vibrio, Campylobacter, and Anaerobes Deck (34)
What is the main cause of ulcers?
how is h pylori spread
person to person fecal to oral
what types of cancers is h pylori associated with
gastic adenocarcinomas and lymphomas
What are the virulence factors of h pylori?
It's a slender, curved, gram- rod with motile polar flagella, that is microaerophilic.
It has a VacA - vacuolating cytotoxin
PAI encoding Type III secretion system
Cag - rearranges cytoskeleton
Pathogenesis of h pylori?
makes urease, allowing persistance, has mcular needle injecting Cag and VacA, leadining to inflammation
What exactly causes the ulcers in h pylori?
the cell destruction by VacA, Cag and immune response
What is the most common bacterial GI infection in developed nations?
What is the reservoir for c jejuni? How many cells are needed for infxn?
sheep, cattle, chickens wild birds dogs
only a few hundred
What is the structure of c jejuni
thin spiral chaped gram-negative rods, with gull-winged appearance
what are the symptoms of c jejuni infxn/
fever, appendicits-like lower abdominal pain, watery diarrhea that progresses to dysentery with blood and pus
What microbe is associated with Guillen-Barre Syndrome?
c jejuni *think "camplybarre"*
Why is campylobacter infxn self-limiting while h pylori can last for decades?
the pathogenesis of h pylori in creating urease allows for a maintenance of hospitable environment. also, lower GI where c jejuni targets has a better clearance mechanism
microbiology of vibrio/
curved gram- rods motile with flagellum, oxidase positive, saltwater in warm months
what are the three significant vibrio classes
cholarea parahaemolyticus and vulnificus
Where is cholera most present?
asia, africa, s america, india
what serogroups of cholera are responsible for the pandemicss?
o1 and o139
what is the infxs dose of cholera/
more than 10^8
What is the presentation of cholera
abrupt onset of vomiting and high volume watery diarrhea
what is the characteristic description of cholera stool?
rice-water stools, speckled with mucus and loaded with bugs
what are the virulence factors of cholera
describe the toxin of cholera
ab toxin comprised of 5b and 1a subunit, causing adpp-ribosylation of gtp-biding protein. activation of adenyl cycle leading to activation of cftr
what are the symptoms of vibrio parahaemolyticus
water diarrhea often with abdom cramps, n/v low grade fever 24 hrs post-exposure,
when do we see v vulnificus
free-living in sea water with consumption of raw oysters and wound infection, leads to immunocompromised or chronic liver pts getting septicemia and bullae
what are the symptoms of v vulnificus
vomiting, diarrhea and abdom cramps
presentation of smell culture witha bscess and tissue necrosis, smelly breath. what are you thinking?
what is the structure of bacteroides fragilis?
gram- antiphagocytic capsul,
what is the structure of prevotella melaningenica?
gram- coccabacillus, antiphagocyte capsule,
what is the colony appearance of prevotella melaninogenica?
what does large, boxcar gram+ rods suggest?
c. perfringens, associated with gas gangrene and cellulitis and food poisoning