Sketchy Micro: Helicobacter

Question 1

Helicobacter is what category of bacteria?

Answer 1

Curved, Gram-negative rod (just like campylobacter and vibrio)

Think of the curved mustache of the helicopter pilot.

Question 2

How can H. pylori survive in the stomach?

Answer 2

It is urease positive, and thus generates ammonia to neutralize acid.

Think of the pilot spraying ammonia on the windshield.

Question 3

Why is the carbon radiolabeled in a urease test?

Answer 3

Because urease breaks down urea into ammonia and CO2, and thus patients will breathe out CO2 if they have H. pylori.

Question 4

What does oxidase do?

Answer 4

It transfers H+ to oxygen, creating either water or hydrogen peroxide.

Question 5

How does H. pylori decrease acid secretion?

Answer 5

It isn’t known, but it’s thought to do so by stimulating somatostatin receptors or inhibiting gastrin.

Question 6

H. pylori increases risk of ___________.

Answer 6

gastric adenocarcinoma (the crab on the helicopter), MALToma (the pile of kleenex –with mucus – that the helicopter pilot tosses away), and duodenal ulcers

Question 7

What is the triple therapy?

Answer 7

PPI (the proton bomb inhibiting the duodenal pump)

Amoxicillin (the AmMO boX next to the pump)

Clarithromycin (the CROw – as in maCROlide –standing on the “keep CLeAR” sign)