Helicobacter

Question 1

Spread?

Answer 1

Human to human via fecal-oral route or gastric secretions.

Question 2

What does it cause?

Answer 2

Duodenal and gastric ulcers

Question 3

T or F. There is an association with gastric adenocarcinomas and lymphomas.

Answer 3

T

Question 4

Shape?

Answer 4

Slender, curved Gram Negative rods

Question 5

Can they move around?

Answer 5

Yes. Motile with polar flagella.

Question 6

Oxygen requirements?

Answer 6

Microaerophilic

Question 7

What are the 4 virulence factors of H. pylori?

Answer 7

1. VacA
2. PAI encoded Type III secretion system
3. Cag
4. Urease

Question 8

What does VacA do?

Answer 8

Vacuolating cytotoxin: punches holes in organelles.

Question 9

What does Cag do?

Answer 9

Rearranges cytoskeleton

Question 10

Why is it important for H. pylori to have urease?

Answer 10

Neutralizes H+ of stomach

Question 11

What causes the ulcers?

Answer 11

Combination of cell destruction by VacA, Cag, and the immune response leads to ulcers.

Question 12

Diagnosis?

Answer 12

1. Endoscopy w/ biopsy and culture
2. Urea breath test
3. Serology useful to monitor recovery

Question 13

Treatment?

Answer 13

1. Omeprazole
2. Metronidazole
3. Clarithromycin