Enteric Bacteria vibrios (3) Flashcards Preview

MSII: Microbiology Unit 6 > Enteric Bacteria vibrios (3) > Flashcards

Flashcards in Enteric Bacteria vibrios (3) Deck (25):
1

Bacteriology of Vibrios

curved gram negative rod

2

What agar is good for culturing vibrios?

bile salts agar - selective for salt tolerance

3

What vibrio has a moderately effective vaccine available?

Cholera

4

What are the reservoirs for cholera?

humans and ocean microbial communities
-indian ocean and gulf of mexico

5

Cholera has two lifestyle forms, what are they and which one is a source of genetic diversity?

planktonic and pathogenic
plank tonic is source of diversity

6

How is cholera transmitted?

fecal oral transmission

7

Where does cholera colonize? How?

colonizes lumen epithelium of small bowel with mucinase and toxin-coregulated pillus - TCP

8

Are alot of cholera bacteria needed to infect someone?

yes - high infectious dose

9

How does cholera create the massive diarrhea it is notorious for? What is the name of this?

choleragen exotoxin
AB signal transduction: A causes persistent activation of adenylate cyclase--> loss of water and ions

"rice water stool"

10

Who is particularly susceptible to a cholera infection?

people on antacids or with gastrectomy
-stomach acid usually kills bacteria

11

How does the cholera bacteria acquire the choleragen gene?

lysogenic bacteriophage CTX

12

What are markers for the presence of CTX?

O1 and O139

13

What is the usual cause of death from cholera?

dehydration and electrolyte imbalance - Acidosis and loss of potassium

14

How would you diagnose and treat dehydration?

skin tenting pinching
treat: IV lacted Ringer solution

NOT just saline- acidosis

15

What antibiotic is available to help shorten the course of cholera? What other vibiro is it effective for?

doxycycline
-parahaemolyticus

16

What are the non-cholera vibrio infections? what are they associated with?

parahaemolyticus, vulcanis
1. self limited gastroenteritis
2. rapid progression cellulitis

17

What is a notorious career that is associated with non-cholera vibrio infection?

working with raw shellfish

18

What is the reservoir for parahaemolyticus and vulcanis

ocean water
they are halophiles - live in high salt

19

What are important co-morbid conditions associated with a poor prognosis for infeciton with parahaemolyticus and vulcanis?

liver or renal disease
immunodeficiency
iron overload

20

What is the typical appearance of cellulitis caused by the non-cholera vibrios?

hemorrhagic bullae

21

How do you treat the cellulitis caused by non-cholera vibrios?

RAPID and aggressive surgery

22

Are systemic symptoms present in cholera infection

usually not, pediatrics it can be since their gut is so thin

23

What is similar about infection with cholera and non-cholera vibirios?

-possibility of dehydration
-self limited course
-efficacy of doxycycline treatment
-site of infection

24

What is not similar about infection with cholera and non-cholera vibrios?

likelihood of dehydration and need for antibiotic

25

V vulnificus is similar to gas gangrene in that it produces what virulence factor?

protease exotoxins