16 Campylobacter and Helicobacter

Question 1

The genus campylobacter: Gram -/+? Aerobe? rod? Oxidase?

Answer 1

Campylobacter genus: 
Gram negative
microaerophile
slender spiral shaped
Oxidase +

Question 2

Where do you find campylobacter mainly?

Answer 2

GI tract of birds

Non-human animals

Question 3

T/F Campylobacter is a thermophile?

Answer 3

true (thrives at temps greater than 50 degrees C)

Question 4

Are campylobacter mobile?

Answer 4

Yes. Motile via polar flagella

Question 5

What organisms causes the most common form of acute infectious diarrhea in developed countries?

Answer 5

Campylobacter Jejuni

Question 6

T/F Campylobacter causes more infections than salmonella and shigella combined?

Answer 6

true

Question 7

Which species of campylobacter causes the most human diseases?

Answer 7

Campylobacter Jejuni

Question 8

How do you usually acquire C. Jejuni?

Answer 8

1) Undercooked poultry (It grows in their guts)

2) unpasteurized dairy products

Question 9

T/F C. Jejuni if left untreated usually results in septicemia?

Answer 9

False.

This is opposite. Salmonella usually causes septicemia if left untreated but C. Jejuni almost never does.

Question 10

What causes Guillain Barre syndrome?

Answer 10

An autoimmune disease that attacks the nervous system. Antigenic mimickry with C. Jejuni. The cross reactivity of o antigens on Campylobacter and myelin proteins.

Question 11

What is the main host for Campylobacter Coli?

Answer 11

Pigs and livestock (virtually the same infection pattern as C. Jejuni)

Question 12

what is the main host for Campylobacter upsaliensis?

Answer 12

Dogs and cats (virtually the same infection pattern as C. Jejuni)

Question 13

What is the reservoir for C fetus and how does this affect pregnant women?

Answer 13

Cattle reservoir.

Causes miscarriage in pregnant women.

Question 14

T/F campylobacter gastroenteritis is often associated with heavy vomiting?

Answer 14

False. This is the exception.

Question 15

If you see bloody diarrhea with a campylobacter infection what does this mean?

Answer 15

That there has been local invasion into the jejunum, ileum, and colon.

Question 16

T/F observation of PMN’s in a simple stain of feces is consistent with campylobacter gastroenteritis?

Answer 16

True. (this tells us its not viral or toxin mediated diarrhea)

Question 17

T/F Campylobacter gastroenteritis and Salmonella gastroenteritis are indistinguishable on clinical evidence alone?

Answer 17

True

Question 18

How many bacteria are required to cause disease in a campylobacter infection?

Answer 18

Only 100-1000 organisms

Question 19

T/F Campylobacter survives within phagocytic cells to cause gastroenteritis?

Answer 19

False. These organism do not survive within phagocytic cells at all.

Question 20

What within the body rapidly kills Campylobacter?

Answer 20

Complement

Antibodies

Question 21

How do you confirm a diagnosis of Campylobacter infection?

Answer 21

Confirmed by isolation in the stool

Question 22

C. Fetalis has a special protein called S protein that works as a _________?

Answer 22

Capsule that prevents C3b binding to the bacteria.

The bacteria that have this are more virulent

Question 23

What is the most important thing to do for the treatment of someone with campylobacter gastroenteritis?

Answer 23

replace fluids and electrolytes

Question 24

Which antibiotics are the best choice for treatment of campylobacter infections in immunocompromized and those with the campylobacter fetalis infections?

Answer 24

Erythromycin and Azithromycin

Question 25

H. Pylori is considered: Gram? Rod? aerobic? fermenter?

Answer 25

Gram - curved rods or spiral shaped micoraerophile non fermenting

Question 26

How is it thought that H. pylori penetrates the wall of the stomach so efficiently?

Answer 26

They are very strong swimmers with a tuft of 4-7 polar flagella. This allows them to burrow in evading the stomach acid.

Question 27

T/F H. pylori is catalase +?

Answer 27

True. | Catalase, oxidase, and urease +

Question 28

H. Pylori gets some of its genetic info from a cag pathogenicity island. What does this encode?

Answer 28

CAG protein that induces inflammation. | cytotoxin associated gene A

Question 29

What is the only bacteria that can colonize the stomach and cause chronic infections ranging from sub clinical to severe ulcer formation?

Answer 29

H. Pylori

Question 30

Why is it difficult to grow H. pylori in culture?

Answer 30

It has very few genes and relies on its host.

Question 31

T/F H. pylori affects half of americans by age 60 and is the most common chronic bacterial infection in humans?

Answer 31

true

Question 32

What causes B gastritis?

Answer 32

H. pylori causes 100% of B gastritis (inflammation of pyloris)

Question 33

H. Pylori causes what percent of gastric and duodenal ulcers?

Answer 33

85% of gastric | 95% of duodenal

Question 34

What are some other reasons for ulcer formation within the GI tract?

Answer 34

NSAIDS | Autoimmune disease

Question 35

H. Pylori increases your risk for which specific types of cancer?

Answer 35

Gastric adenocarcinoma and B cell lymphoma

Question 36

How does H. pylori not get killed by the stomach acid?

Answer 36

It hydrolyzes the urea to NH4 and CO2 using urease to cause a small neutral zone around itself until it is able to burrow in the gastric wall enough to avoid the low Ph.

Question 37

How does H. pylori attach to epithelial cells in the stomach?

Answer 37

BAbA protein and other adhesins

Question 38

How does H. pylori cause ulcers?

Answer 38

1) bacteria release toxins which leads to a lot of inflammation. 2) PMN's and B and T cells migrate to area and begin killing not only bacteria but also the mucous membrane of the stomach. This may occur because of molecular mimicry between H. pylori and gastric mucosa. 3) without this mucous membrane in place for protection, an ulceration forms.

Question 39

What is the CLO test?

Answer 39

a rapid urease test checking for H. pylori

Question 40

T/F H. pylori antigens can be detected in the stool?

Answer 40

true

Question 41

T/F antibodies against H. pylori can be detected to indicate current or past infections?

Answer 41

true

Question 42

What is the simple principal behind the urea breath test that checks for H. pylori?

Answer 42

1) Patient ingests C13 or C14 labeled urea 2) If H. pylori is present= urea is hydrolyzed 3) The labeled CO2 is measured on exhalation

Question 43

What is the best method for detecting H. pylori?

Answer 43

The urea breath test using radiactive carbon

Question 44

How do you treat H. pylori?

Answer 44

1) PPI 2) Bismuth (It has some antibacterial activity and helps with inflammed gastric mucosa) 3) two or three antibiotics