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Flashcards in GI: Cases Deck (26)
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1
Q

A patient presents with the following, which is concerning for…

  • indegestion, abd. pain, oily diarrhea
  • relief via eating and antacids
A

zollinger-ellison syndrome

2
Q

What imaging modality is used to assess potential ulceration in zollinger-ellison syndrome?

A

endoscopy

3
Q

What four lab tests can be administered to evaluate for zollinger ellison syndrome?

A

Serum gastrin, Basal Gastric H+, Pentagasatrin stimulation test, secretin stimulation test

4
Q

What results would you expect in zollinger-ellision when taking a serum gastrin and basal gastric H+ secretion?

A

highly elevated

5
Q

What is the expected result of pentagastrin stimulation test in zollinger-ellison?

A

no increase

6
Q

what is the expected result of secretin stimulation test in zollinger-ellison?

A

increase to 1000 pg/ml

7
Q

With zollinger-ellison, what may be seen on CT?

A

gastrinoma

8
Q

Laproscopic surgery is definitive tx for zollinger-ellison. What drug should be given while awaiting surgery?

A

omeprazole (PPIs)

9
Q

What is the cause of excess gastrin release in Zollinger-ellison? Is it regulated by feedback mechanisms?

A

gastrinoma

no feedback regulation

10
Q

Where are gastrinomas commonly located?

A

duodenum or pancreas

11
Q

What doesn’t pentagastrin stimulation (a gastrin analogue) have any effect in zollinger-ellison?

A

H+ secretion already maximal

12
Q

In the secretin stimulation test, secretin stimulates which cells to release gastrin?

A

gastrinoma cells, not G cells

13
Q

What causes steatorrhea in zollinger-ellison?

A

pancreatic lipase inhibition due to low pH

14
Q

a complete ileal resection would result in a loss of _____ meters.

A

2 to 4 meters

15
Q

An ileal loss of more than _____ cm will distrupt enterohepatic circulation of what substance?

A

100 cm

bile salt recovery

16
Q

What is causing steatorrhea in ileal resection

A

liver cant replete bile salts fast enough, fecal loss is too great

17
Q

What is the mechanism by which cholestyramine can treat diarrhea?

A

they limit cl- and fluid secretion, reducing diarrhea

18
Q

Why must b12 be injected in patients with ileal resection?

A

The IF-b12 complex is absorbed in the ileum

19
Q

What is the most common site of gastric ulcer caused by h. pylori?

A

antrum

20
Q

h. pylori releases what which breaks down protective mucous?

A

cytotoxins

21
Q

What allows h. pylori to survive the acidic environment of the stomach?

A

urease conversion of urea to NH3 to NH4+

leads to alkalinization

22
Q

In the duodenum, H. pylori decreases the secretion of what substance, which leads to duodenal ulcer?

A

bicarb

23
Q

What three tests are available for diagnosing H. pylori?

A

h. pylori Ab tests, C13-urea breath test, endoscopic biopsy

24
Q

C13 urea is metabolized to what by h. pylori urease which can be measured upon expiration?

A

CO2-13

25
Q

What two meds treat h. pylori?

A

antibiotic + PPI

26
Q

a PPI blocks what channel?

A

Potassium-H+ ATPase