Vibrio, Campylobacter, Helicobacter Flashcards
What virulence factors of V. cholerae helps the organism adhere to the intestinal tract and causes the body to dump water into the intestinal lumen, which may lead to dehydration and death?
- Adhesins
- Single polar flagella
- Toxin co-regulated pili (TCP Type IV)
- Hemagglutinin protease
Cholera toxin binds to _____ found on many different cell types.
Ganglioside
How does Cholera toxin cause net excretion of electrolytes then water from cells?
- A1 subunit ADP ribosylates protein Gsa →
- Locks adenylyl cyclase into perpetual on cycle →
- Increase cAMP →
- Net excretion
T/F Cholera toxin is enoded in V. cholerae’s chromosome
FALSE
Cholera toxin is phage encoded
V. cholerae _____ (a virulence factor) directly correlates with its virulence. Its presence indicates more severe symptoms. What serological group of this factor causes the majority of disease?
- O1 antigen
- Serogroup Inaba (El Tor) causes majority of disease
What is the only non-O1 derivative that does not produce milder illness by V. cholerae?
O139
The serious form of Cholera is acquired by _____
Consumption of contaminated seafood
Patients with cholera produce massive amounts (10-15L) of stool *without fever* that has a characteristic _____ appearance
Rice water stool
T/F V. cholerae invades host cells
FALSE
No invasion → no direct tissue damage → no fever
V. cholerae is sensitive to _____ and _____
- Drying
- Acidic pH
- Pts. with achlorhydria or those taking antacids are more susceptible
When cultured on ____ agar, V. cholerae grows as _____ colonies that ferment _____ and _____
- TCBS agar
- Grows as yellow colonies
- Ferment sucrose and citrate
Upon gram staining, V. cholerae appear as _____
- Comma shaped gram negative rods
- Look like seagulls in pairs
What is the treatment for Cholera?
- IV fluid/electrolyte replacement
- Tetracycline
- Reduces severity/length
In contrast to V. cholerae, V. parahemolyticus _____ intestinal epithelium with _____
Invades with invasins
In contrast to V. cholerae, the diarrhea caused by V. parahemolyticus is _____
Inflammatory (V. cholerae diarrhea is secretory)
What is the name of the hemolysin produced by V. parahemolyticus?
Kanagawa toxin
V. parahemolyticus is acquired via _____
Consumption of contaminated seafood