P. aeruginosa - H. pylori

Question 1

This is a Gram (+) curved rod, aerobic, and mobile. It’s oxidase positive. Some strains with capsule appear mucoid. It has polar flagella.

Answer 1

P. aeruginosa

Question 2

How is p. aeruginosa ID’d?

Answer 2

lactose non-fermenter, grape-like odor, green color on MA, non-fastidious (4-42 degrees, tap water)

Question 3

P. aeruginosa is the #1 cause of infection in which patients?

Answer 3

cystic fibrosis patients

Question 4

P. aeruginosa is non normal flora, but ubiquitous where?

Answer 4

in nature and moist hospital environments

note: mostly nosocomial

Question 5

P. aeruginosa is the leading cause of ____-associated pneumonia.

Answer 5

ventilator

note: tracheobronchitis to necrotizing bronchopneumonia can be seen

Question 6

In regards to bacteremia caused by P. aeruginosa, it is similar to other Gram (-) bacteria but the patient may develop ______ ______, which are small or large painful maculopapular lesions that start out pink but progress to purple/black necrotic lesions

Answer 6

Ecthyma gangrenosum (painful, unlike B. anthracis)

Question 7

P. aeruginosa can cause pyoderma where?

Answer 7

face

Question 8

P. aeruginosa can also cause eye infections - ____ ___ under soft contact lens can lead to vision loss

Answer 8

corneal ulcer

Question 9

P. aeruginosa can cause OTITIS EXTERNA. Describe the symptoms.

Answer 9

mild to severe destruction of cranial bones!; itching, pain, mucopurulent discharge, lumen narrowed; “swimmers ear”

Question 10

P. aeruginosa can cause endocarditis, commonly in what individuals? What part of the heart is affected?

Answer 10

IV drug users; tricuspid wall (unique endocarditis)

Question 11

P. aeruginosa causes a ton of virulence factors that cause chronic lung infections due its ability to do what?

Answer 11

tightly adhere to mucus and damper host immune system

Question 12

This is a curved, Gram (-) rod that is highly motile. It is oxidase positive and has darting motility. It is a sucrose fermenter, meaning it grows yellow on TCBS agar and can be ID’d in the stool.

Answer 12

Vibrio cholerae

Question 13

The natural habitat of Vibrio cholerae is where? How is it transmitted?

Answer 13

salt water; fecally contaminated water

Question 14

Serotypes 01 and 0139 of Vibrio cholerae are associated with disease. Which one doesn’t need toxin to cause disease?

Answer 14

01

Question 15

Vibrio cholerae causes cholera. Describe the incubation period, onset, and symptoms

Answer 15

incubation: 1-3 days
onset: sudden
symptoms: NO FEVER, vomiting, severe but painless diarrhea, muscle cramps, hypovolemic shock, metabolic acidosis, hypokalemia

Question 16

What type of stools does one produce when they have cholera?

Answer 16

rice water stools (mucus flecks)

Question 17

Pathogenic strains of Vibrio cholerae are not capsulated. What is the significance of this?

Answer 17

infection confined to GI tract

Question 18

This virulence factor of Vibrio cholerae is a bacteriophage encoded toxin with a co-regulated pilus - allows adherence and phage binding

Answer 18

cholera toxin

Question 19

These two bacteria are curved Gram (-) rods that are oxidase positive, have darting motility. They are non-sucrose fermenters, meaning they grows green on TCBS agar and can be ID’d in the stool.

Answer 19

Vibrio parahaemolyticus and Vibrio vulnificus

Question 20

Vibrio parahaemolyticus and Vibrio vulnificus require what? How do they infect?

Answer 20

salt; seafood/water

Question 21

What diseases do Vibrio parahaemolyticus and Vibrio vulnificus cause?

Answer 21

Vibrio parahaemolyticus: gastroenteritis (diarrhea w/ no blood); wound infections from water

Vibrio vulnificus: Septicemia (after eating raw oysters); wound infections from water - erythema, pail bullae, necrosis

Question 22

Vibrio vulnificus has enhanced virulence with high ___

Answer 22

iron

Question 23

Vibrio parahaemolyticus has virulence factor that leads to increased Ca, and thus Cl loss. What is the name of this?

Answer 23

thermostable direct hemolysin (TDH)

Question 24

This is a Gram (-) curved rod. It is oxidase positive and grows on TCBS agar, not halophile.

Answer 24

Aeromonas hydrophila

Question 25

Aeromonas hydrophila is free living in fresh and salt water. What is the source of infection?

Answer 25

undercooked seafood; water

Question 26

What diseased does Aeromonas hydrophila cause?

Answer 26

gastroenteritis, wound infections, and system diseases in IC patients

Question 27

This bacteria is a Gram (-) curved or S-shaped rod. It can’t ferment/oxidize carbohydrates. It has darting motility. It grows on Campy-BAP media and MCCD agar

Answer 27

Campylobacter sp.

Question 28

Campylobacter sp. (C. jejuni) is the #1 cause of bacterial _____ in the US.

Answer 28

gastroenteritis

note: can come from poultry, milk, meat, or H20

Question 29

Infection by Campylobacter sp. is more common in what season? Transmission from person to person is ____

Answer 29

summer; low (high dose necessary)

Question 30

Describe the progression of the gastroenteritis caused by C. jejuni - incubation, onset, and symptoms

Answer 30

incubation: 2-4 days
onset: HA, myalgia, malaise 12-48 h
symptoms: onset followed by diarrhea, fever, fecal leukocytosis, abdominal pain; no blood to bloody loos stools are possible

Question 31

Gastroenteritis from C. jejuni causes 20-40% of ____-____ syndrome

Answer 31

Guillain-Barre

Question 32

In regards to disease caused by types of Campylobacter sp., this type causes septicemia

Answer 32

C. fetus

Question 33

Describe the virulence of C. jejuni

Answer 33

endocytosed by MC, epithelial cells and M cells -> host cell death, bowel ulceration, inflammation, EOSINOPHILS infiltrate the lamina propria

Question 34

Describe the virulence of C. fetus

Answer 34

has capsule that allows it to infect systemically

Question 35

This is a Gram (-) spiral rod with 4-6 polar flagella. It’s ID’d by Urea breath test and serological tests for IgG. It’s oxidase positive

Answer 35

H. pylori

Question 36

How is H. pylori spread?

Answer 36

fecal-oral or oral-oral

Question 37

What two diseases does H. pylori cause?

Answer 37

Chronic Gastritis; Gastric and Duodenal ulcers - increased risk of stomach cancer and gastric MALT lymphoma

Question 38

H. pylori makes a ton of virulence factors. Urease is an important one. What does it do?

Answer 38

produces ammonia to raise pH, allows survival in stomach