GI Lower Bacterial Infections II

Question 1

What does Vibrio spp. look like?

Answer 1

G- flagellated curved rod

Question 2

What distinguishes Vibrio sp. from E. coli?

Answer 2

Vibrio: Oxidase + (shows up purple), flagella

E. coli: Oxidase -

Question 3

What are symptoms of Vibrio parahaemolyticus infection?

Answer 3

Bloody diarrhea
Stomach cramps, nausea, vomiting
Fever
Sx less than a week

Question 4

How do you diagnose V. parahaemolyticus?

Answer 4

Cultures of stool, wound, blood

Question 5

What is the mechanism of action of V parahaemolyticus infection?

Answer 5

Enterotoxin (hemolysins)

Question 6

Food reservoirs for Vibrio parahaemolyticus?

Answer 6

Uncooked shellfish

Question 7

What does listeria look like?

Answer 7

Gram positive bacillus

Question 8

What hemolysis does listeria exhibit?

Answer 8

Beta hemolysis but only directly under colonies

Question 9

Who are more vulnerable for listeriosis, causing a more severe illness?

Answer 9

Older adults
Pregnant women
Newborns
Immunocompromised

Question 10

What are the causes of death with listeriosis while vulnerable?

Answer 10

Meningitis and sepsis

Question 11

How do you diagnose listeriosis?

Answer 11

Positive ID is bacteria found in normally sterile site

Question 12

What is the mechanism of injury for listeria?

Answer 12

Invasion of macrophage (trojan horse)

Liver is major target

Question 13

What are reservoirs for listeria?

Answer 13

Sprouts
Deli meats/hot dogs
Smoked salmon
Soft cheeses
Raw milk

Question 14

What are shigella closely related to?

Answer 14

E. coli

Question 15

How is shigella transmitted?

Answer 15

Fecal oral

Question 16

What are symptoms of shigella sonnei infection?

Answer 16

Bloody diarrhea (sometimes not)
Fever
Cramps
1-2 days following exposure
5-7 day resolves

Question 17

What is defined as Frequent small bowel movements with blood and mucus, accompanied by rectal pain and spasms?

Answer 17

Dysentery

Question 18

Easy way to tell E. coli from e. coli?

Answer 18

Shigella have no flagella

Lactose negative and H2S negative

Question 19

What cells are initial invasion points of shigella?

Answer 19

M cells

Question 20

What do shigella use to move around in a host?

Answer 20

Actin

Question 21

How do you treat shigella?

Answer 21

Usually resolves

Can be systemic so use antibiotics

Question 22

What are possible complications of shigella?

Answer 22

Hemolytic uremic syndrome

Reactive arthritis

Question 23

What does Shiga toxin affect?

Answer 23

Vascular endothelial cells (most severe dysentery)

Question 24

What strains of E. coli cause disease?

Answer 24

ETEC and EHEC

Question 25

What diseases are caused by E. coli?

Answer 25

Diarrhea Urinary tract infection Neonatal sepsis Gram negative sepsis

Question 26

What are the E coli that produce sign toxin called?

Answer 26

Enterohemorrhagic E. coli (EHEC)

Question 27

Which E coli is more responsible for outbreaks in U.S.? Which is more common in traveler's diarrhea/children's diarrhea?

Answer 27

EHEC: US outbreaks ETEC: Traveler's/Children

Question 28

What are common symptoms for E coli infection?

Answer 28

Profuse watery diarrhea Nausea with or without vomiting Chills Long incubation period for EHEC

Question 29

Should you treat E coli poisoning?

Answer 29

Not really. Will kill normal gut flora as well

Question 30

What are used for tracking E coli outbreaks?

Answer 30

Commercial PCR and Ig-based kits

Question 31

What are common EHEC/ETEC reservoirs?

Answer 31

Beef, spinach, etc.

Question 32

What is primary reservoir for V. cholerae?

Answer 32

Water

Question 33

What does cholera toxin do?

Answer 33

Activates adenylate cyclase, leading to Cl excretion and Na absorption (water follows Cl)

Question 34

Which serogroups of V. cholerae produce cholera toxin?

Answer 34

O1 and O139

Question 35

What does cholera look like?

Answer 35

Profuse watery diarrhea (rice-water stools) Vomiting Rapid HR SEVERE dehydration

Question 36

What is the only reliable method of identifying V. cholerae?

Answer 36

Culture of stool

Question 37

How do you treat cholera?

Answer 37

Rehydration therapy | Sometimes antibiotics if super serious

Question 38

What is the common source for Salmonella Typhi?

Answer 38

untreated water (humans are only carriers)

Question 39

What does typhoid fever look like?

Answer 39

High fevers (103-104) Weakness, headache Stomach pain, loss of appetite, diarrhea OR constipation Rash of flat, rose-colored spots

Question 40

How do you treat typhoid fever?

Answer 40

Vaccine | Antibiotics are recommended

Question 41

What does C. diff look like?

Answer 41

Gram + bacilli, spore forming

Question 42

What do C. diff exotoxins cause?

Answer 42

Cell death, shallow ulcers, pseudomembranes

Question 43

How do you diagnose C diff?

Answer 43

Toxin detection

Question 44

How do you treat C. diff?

Answer 44

Antibiotics: Metronidazole, vancomycin If severe, then bowel resection Maybe fecal transplant