Clinical Cases Flashcards
What’s the name of the condition where you have a gastrinoma?
Zollinger-Ellison Syndrome
What will happen to gastric H+ secretion if you have Zollinger-Ellison Syndrome?
VERY high
If you have Zollinger-Ellison syndrome and you do a pentagastrin stimulation test, what will happen to H+ secretion?
It won’t be increased since H+ secretion is already maxed out
What will happen to someone with zollinger Ellison syndrome if you do a secretin stimulation test?
Gastrin will increase
Gastrin secretion by gastrinomas (is/is not) controlled by feedback mechanisms
Is not
What’s the big deal if you have hypersecretion of gastrin anyways?
Can cause ulcers and hypertrophy of the gastric mucosa
How do you treat acid hypersecretion’?
Proton pump inhibitors (omeprazole)
What happens to normal people if you do a pentagastrin stimulation test?
Pentagastrin would stimulate H+ secretion to levels 3x higher than normal
In zollinger Ellison syndrome, giving secretin causes the release of ________
Gastrin
In normal people, giving secretin would have what effect on gastrin release?
Gastrin would stay the same or decrease
Why does someone with zollinger Ellison syndrome have steatorrhea (oily stool)
Pancreatic lipase will be denatured by the extremely high pH in the small intestine
Why would someone who’s missing 80% of their ileum have diarrhea and oily stools?
No bile salt reabsorption= losing bile salts faster than liver can replace them.
Deficient bile= impaired lipid digestion= oily stool
Bile salts entering large intestine= stimulation of water secretion and intestinal motility= diarrhea
******
How could you treat the diarrhea suffered by someone with 80% of their ileum removed?
Cholestyramine/bile acid binding resin will bind to the bile salts and “hide” them from the large intestine so it won’t freak out and cause a bunch of water secretion and diarrhea when bile salts enter the colon.
How much bile salt usually makes it into the colon?
Almost none!
What vitamin will our patient who is missing 80% of his ileum be deficient in?
B12
It is absorbed in the ILEUM bound to intrinsic factor***
How do we treat B12 deficiency if patient is missing 80% of their ileum?
B12 injections (oral b12 will do nothing)
What two tests can be done to diagnose H Pylori?
Serological test- looking for antibodies against H Pylori
13C-Urea breath test
How does the 13C-Urea Breath test look for H pylori?
Patient is given urea labeled with 13C. H Pylori urease will metabolize it to 13CO2 and NH3.
13CO2 is breathed out and measured.
How does H Pylori cause gastric ulcers?
It releases cytotoxins that break down the protective mucus
How can h pylori survive in the low pH of the stomach?
It has urease which converts urea to NH4+, which alkalinizes the environment
How does H Pylori cause ~duodenal~ ulcers?
Two ways:
Inhibits D cells= no somatostatin= G cells go crazy making gastrin= tons of H+ secretion
Inhibits HCO3- secretion in pancreatic ductal cells
How do you treat H Pylori infection?
Antibiotic
Antacid
