Gastric Disorders B&B Flashcards
state 4 common causes of acute gastritis
- NSAIDs: block prostaglandin production (inhibits H+ secretion)
- alcohol: direct mucosal damage
- chemotherapy: inhibits epithelial cell replication
- H. pylori
which patients get Curling’s Ulcers?
burn patients
loss of skin = loss of fluids/dehydration —> decreased plasma volume/ hypotension to stomach —> mucosal damage
give PPP
what is the cause of Cushing’s Ulcer?
increased intracranial pressure (tumor, hemorrhage) causes vagal stimulation —> ACh causes excess acid production
high ICP —> high vagal tone —> high ACh —> high H+ secretion
give PPP
what is the mechanism of stress ulcers?
shock/sepsis/trauma causes decreased mucosal perfusion —> loss of protective barrier of mucus/bicarb
common in ICU patients, PPP given prophylactically (pantoprazole, omeprazole)
name 2 proton pump inhibitors often given prophylactically to ICU patients to prevent stress ulcers (due to hypotension)
- pantoprazole
- omeprazole
and others, obvs
Type A vs Type B chronic gastritis
Type A = autoimmune (pernicious anemia)
Type B = H. pylori
describe the pathology of autoimmune gastritis
aka pernicious anemia: autoimmune destruction of gastric parietal cells —> loss of intrinsic factor secretion, needed for B12 absorption in the terminal ileum
inflammation occurs in body and fundus of stomach
intrinsic factor is needed for B12 absorption in the ______
terminal ilium
where does inflammation occur in autoimmune gastritis, and with what cancer is this associated?
aka pernicious anemia: autoimmune destruction of gastric parietal cells —> loss of intrinsic factor secretion, needed for B12 absorption in the terminal ileum
chronic inflammation occurs in gastric body/ fundus, and associated with gastric adenocarcinoma
with which HLA genes is autoimmune gastritis associated?
aka pernicious anemia: autoimmune destruction of gastric parietal cells —> loss of intrinsic factor secretion, needed for B12 absorption in the terminal ileum
associated with HLA-DR antigens and more common in women
where do ulcers caused by H. pylori occur? (specifically)
pyloric antrum of stomach - distal end close to duodenum
does not invade mucosa, sits ontop of epithelial cells and secretes urease to survive low pH
which 2 malignancies are associated with H. pylori?
- gastric adenocarcinoma
- MALT lymphoma (B-cell)
how does the urea breath test work for diagnosing H. pylori infection?
patients swallow radio-labeled urea
when H. pylori secretes urease, it splits urea to produce isotope-labeled CO2, which is detected in exhaled breath
what is the triple therapy for H. pylori infection?
- proton pump inhibitor (PPP)
- clarithromycin
- amoxicillin/ metronidazole
testing often repeated to confirm eradication
Zollinger-Ellison Syndrome
rare cause of duodenal ulcers, due to gastrin secreting tumor
cause development of multiple ulcers in duodenum, may also develop ulcers in distal duodenum or jejunum