GI: gastric disease Flashcards
What two enzymes are produced by the stomach to aid in digestion?
Pepsin, gastric lipase
A small amount of instrinsic factor is produced by what cells in the dog stomach?
Parietal cells and cells at the base of the antral glands
What breeds are predisposed to hypertrophic gastropathy?
Shih Tzu, Basenji
What breed is predisposed to atropic gastritis?
Lundehund
Prior to measuring serum gastrin, omeprazole/famotidine must be discontinued for how many days?
1 week
What non-gastric diseases can cause an increase in gastrin?
Renal and hepatic dysfunction
A gastric pH<3 with an increased serum gastrin raises concerns for that disease process?
Gastrinoma (Zollinger-Ellison)
Mast cell tumors and hyperhistaminemia can induce gastric acid secretion. What would the serum gastrin level be?
Low
In patients with achlorhydria, what would serum gastrin and gastric pH be?
pH >3 with increased serum gastrin (in humans, pH <2.5 with gastrin >1000 is diagnostic)
If a gastrinoma is suspected, what IV infusions can be given for further investigation?
Secretin or Ca - neither of these lead to release of gastrin in a normal animal, but both lead to gastrin release from a gastrinoma (highest 2 and 5 minutes after secretin, 60 min after Ca)
What are 3 consequences of a gastrinoma?
Gastric antral hypertrophy, hyperacidity, and ulceration
Where is the most common location for a gastrinoma?
Right limb or body of the pancreas
What percent of gastrinomas have metastasized at the time of diagnosis?
85% (LN, mesentery, spleen, liver)
What prostaglandin is gastroprotective?
PGE2
Where are NSAID induced ulcers typically located?
Antrum
What is the main side effect of omeprazole?
Diarrhea
What is octreotide?
Long acting somatostatin analog
How does octreotide affect gastrin/gastric acid?
Directly decreases the secretion of gastrin and therefore gastric acid production - can be used in gastrinomas
What is misoprostol and what is it used for?
PGE2 analog - protects against NSAID induced ulceration without altering gastric acidity
How does sucralfate work?
Binds to areas of denuded epithelial mucosa
Does prophylactic administration of misoprostol, cimetidine, and/or omeprazole prevent gastric erosions in dogs on steroids?
No, unlike with NSAIDs. Cause of ulceration due to steroid use is unknown
How do mast cell tumors induce vomiting?
Histamine causes H1 activation of the chemoreceptor trigger zone; H2 activation of gastric acid secretion
What is the mechanism of action for metoclopramide?
Antagonizes D2-dopamingeric and 5HT3-serotonergic receptors, agonist of 5HT4, cholinergic effects on smooth muscle
What is the mechanism of action of ondansetron?
Antagonized peripheral 5HT3 receptors
What is the mechanism of action of maropitant?
Antagonized NK1 (neurokinin 1) receptors
Maropitant has been associated with bone marrow hypoplasia in what age of dogs and cats?
Dogs <8 weeks, Cats <16 weeks
Gram negative or pathogenic bacteria induce the release of what cytokines from epithelial cells?
Proinflammatory - IL-8, IL-1 beta