Clinical Approach - Stomach Dz Flashcards
What are three major stimuli and two major inhibitors of parietal cell acid secretion?
stimuli - histamine, Ach, gastrin
inhibitors - somatostatin, hydrogen ions, prostaglandins
What is the mediator that protects the gastroduodenal mucosa from acid injury?
prostaglandins secrete mucus, stimulate bicarb secretion, and maintain mucosal blood flow
What is the basic pathophysiology of ulcer disease?
mucosal defenses unable to protect, rather than too much acid - most pts secrete normal amt of acid
What are the two most common etiologies for ulcer dz?
H. pylori
NSAIDs
What is the most specific symptoms of peptic ulcer?
nocturnal pain relieved by antacids
How can you tell if a perforation is present in pts with ulcer dz?
acute dev of peritonitis
pancreatitis w pain pattern diff than usual indicates penetration
What are the five most common gastric neoplasms?
adenocarcinoma gastric polyps stromal tumors and GISTs neuro-endocrine tumors lymphoma
What is the relationship between H pylori and gastric adenocarcinoma?
adenocarcinoma prevalance is falling, tracking h pylori
h pylori may facilitate dev of adenocarcinoma - other needed factors are unclear
uncertain rather eradication of h pylori will lead to regression of pre-neoplastic lesions
What are the three types of gastric polyps?
fundic gland - long term PPI use, unrelated to H pylori, usually no clinical significance
adenoma - risk of carcinoma, FAP
hyperplastic - hypergastrinemia from autoimmune body gastritis, no risk of adenocarcinoma
What are stromal tumors and GISTs?
benign or malignant
submucosal, subserosal or both = dumbbell
larger may have pain and bleeding
GISTs specifically express cKIT - respond to Gleevec
What are neuroendocrine tumors in the stomach?
carcinoid tumors from enterochromaffin-like cells - usually silent but metastasis to liver can produce carcinoid syndrome
antrectomy can cure, sometimes endoscopically
What are the two types of carcinoid tumors of the stomach?
sporadic type - single or few in number, may metastasize, surgically remove, more dangerous
pts with achlorhydria - smaller and more numerous, from autoimmune gastritis
Why should CT scan and EUS staging of the lesion be performed in all cases of suspected MALT?
to avoid missing hidden high grade lymphoma
