E. coli

Question 1

what does E. coli synthesize in the human body?

Answer 1

vitamin K

Question 2

name seven pathogenic E. coli:

Answer 2

1) EHEC - enterohemorrhagic
2) STEC - shiga toxin
3) EPEC - enteropathogenic
4) EAEC - enteroaggregative
5) EIEC - enteroinvasive
6) ETEC - Enterotoxigenic
7) DAEC - diffuse adhering

Question 3

STEC/EHEC serogroups

Answer 3

O157:H7, O111, O26, O157:H-, O104:H4 (Germany)

Question 4

STEC/EHEC places of infection

Answer 4

• food
• petting zoos
• person to person

Question 5

STEC/EHEC infectious dose

Answer 5

very low

Question 6

Do STEC/EHEC have T3SS?

Answer 6

yes

Question 7

what is the pathogenicity island for T3SS called in STEC/EHEC?

Answer 7

LEE

Question 8

What does LEE encode?

Answer 8

intimin and tir

Question 9

what is tir?

Answer 9

T3SS secreted bacterial protein that is delivered tot he sure of the epithelial cells to allow for E. coli attachment

Question 10

what is intimin?

Answer 10

on the surface of E. coli and binds to tir

Question 11

what can cause HUS (hemolytic uremic syndrome)?

Answer 11

shiga toxin or shiga-like toxin in E. coli dysenteriaea

Question 12

symptoms of EHEC/STEC

Answer 12

• abdominal pain
• bloody diarrhea
• HUS
• acute renal failure

Question 13

STEC and EHEC are grouped as:

Answer 13

enterohemorrhagic E. coli

Question 14

what are the diarrheagenic E. coli?

Answer 14

• EPEC
• ETEC
• EAEC
• EIEC
• DAEC

Question 15

characteristics of EPEC

Answer 15

• person to person contact
• leading cause of diarrhea in developing countries
• forms A/E lesions
• toxins not detectable in stool

Question 16

characteristics of ETEC

Answer 16

• traveler’s diarrhea
• enterocytes in SMALL INTESTINE
• produces heat labile and heat stable toxins (LT and ST) which lead to fluid loss

Question 17

characteristics of EAEC

Answer 17

• similar to EPEC but somewhat more aggressive due to stronger epithelial attachment
• no A/E lesions
• EAST and hemolysin produced

Question 18

characteristics of EIEC

Answer 18

• symptoms similar to shigella

- no LT or ST produced

Question 19

characteristics of DAEC

Answer 19

• diarrhea in older children in developing countries

Question 20

Does E. coli ferment lactose?

Answer 20

yes

Question 21

treatment of ETEC

Answer 21

loperamide (may be combined with fluoroquinolones)

Question 22

treatment of EAEC

Answer 22

fluorquinolones for traveler’s and those with HIV