Stomach Flashcards
HCl secretion importance
denatures proteins, protect from infection, absorption of Fe/B12
What triggers slowing in gastric emptying
decreased pH (acid), fatty acids and caloric density, increase in osmolality
Types of Gastritis
infectious, lymphocytic, Eosinophilic, gastritis associated with systemic disease
Autoimmune Atrophic Gastritis
autoimmune attack against parietal cells, IF
Causes of Infectious gastritis
Bacterial (H pylori, syphilis, TB)
Fungal (candidiasis, aspergillosis, histoplasmosis, mucormycosis)
Parasitic (giardia, cryptospyridia, etc)
Viral (CMV)
Peptic ulcer disease original hypothesis
thought to be all from stress-lifestyle –>increased acid
Helicobacter pylori
most common human bacterial infection, which is life-long for most–most asymptomatic
- makes urease enzyme to neutralyze stomach acid by creating ammonia from urea
Strain of H pylori associated with pathogenicity
CagA
- associated with duodenal and gastric ulcers
VacA– exotoxin, pores in membrane, inhibit T cells
H pylori risks
Gastric cancer
gastic lymphoma
atrophic gastritis
Peptic ulcer
Chronic gastritis
presence of mononuclear inflammatory (lymphocytes and plasma cells) cells within lamina propria
Progression of gastritis
Colonized mucosa –> superficial gastritis – gastric atrophy– intestinal metaplasia – dysplasia – gastric adenocarcinoma
Antral predominant infection associated with
acid secretion adn duodenal ulcer (DU)
Duodenal ulcer (DU)
gastric metaplasia in duodenum (H pylori colonize –>inflammation –> cell damage –>ulcer)
what is severity of body gastritis correlated with
acid secretion inversely correlates with severity of gastric body gastritis
Diagnosis of H pylori
Endoscopy Mucosal biopsy
- Histology, Rapid urease test
No mucosal biopsy required
- Blood antibody test, stool antigen test, urea breath test (not as common)
Treat H pylori infection
- triple therapy (PPI + clarithromycin + amoxicilin 10-14 days)
- Rescue quadruple therapy (PPI + metronidazole + tetracycline + bismuth)
- Sequential therapy
when to treat H pylori
Peptic ulcer disease, gastric lymphoma, fam hx of gastric carcinoma, whenever diagnosed??
Other causes of gastritis
Non H pylori infection – uncommon (CMV, Candidiasis, Aspergillosis, etc)
Eosinophilic (
- can have ulceration - early satiety, nausea, vomiting - increased eos in blood - rare, cause unknown
Thickened folds
H. pylori, neoplasia, Menetrier’s disease, lymphocytic infiltration, acid hypersecretory states
Menetrier’s Disease
very very rare; increased mucous secretion, decreased acid; abdominal pain, weight loss, bleeding, hypoalbuminemia
Non-inflammatory Epithelial cell injury also called…
Gastropathies
Gastropathy
gastroduodenal injury in absence of significant inflammation
- NSAIDs
- Ethanol
- Stress ulceration
- Cocaine
- Bile reflux
ethanol gastropathy
similar to NSAID type injury; disrupts mucosa and increased acid secretion
- PUD with high concentration (>10%), high amounts of use, NSAID use
GI side effets of NSAID use
heartburn, nausea, vomiting, abdominal pain; mucosal lesions - 20% in 3 months
GI complications– perforated ulcers or GI bleeding
Gastric protective mechanisms
ALL PG dependent
- mucous layer thickness
- cell membrane hydrophobicity
- bicarb secretion
- mucosal blood flow
- epithelial cell migration/proliferation
Stress ulcers
ICU patients
- CNS injury (cushing’s ulcer), Burns (Curling’s ulcer), prolonged mechanical ventilation > 48 hours, coagulopathy
- fundus and body,
impaired mucosal protection, incerased acid secretion
Peptic ulcer complications
abdominal pain, anemia, bleeding, acute bleed (hematemesis melena–black tarry smelly stool), perforation (5% lifetime), Gastric outlet obstruction-duodenal ulcer
Treatment of Severe PUD -acute bleeding
- IV resuscitation –>restore IV volume
- acid suppression - PPI drip (improves clotting)
- Endoscopy
- Angiography- coils
Surgery
Treatment of severe PUD with perforation
Surgery
Treat PUD
PPI therapy, H pylori test and treat, risk factor avoidance (NSAIDs, smoking, chronic PPI if NSAID needed for cardiac disease)
Types of gastric neoplasms
polyps, adenocarcinoma, stromal tumors, neuro-endocrine tumors, lymphoma
Gastric polyps
Hyperplastic, adenomia, fundic gland polyps (common-benign and unrelated o H pylori)
Hyperplastic gastric polyps
found near gastritis ulcer; rare,malignant potential (>1 cm)
Adenoma (gastric polyp)
Premalignant, FAP
Fundic gland polyps
type of gastric polyp associated with chronic PPI use; benign and unrelated to H pylori
2nd most common cancer world-wide
gastric Adenocarcinoma
2nd most common cause of death from cancer world-wide
gastric adenocarcinoma
Gastric cancer treatment
Surgery (endoscopic removal for stage 0), Chemo, Radiation
GIST
distinct stromal tumor —most common in mesenchymal tumor of stomach (60%)
- Leiomyomas NOT GISTs
Treatment of GIST
Gleevec
Prognosis of GIST compared to other stromal tumors
WORSE
GISTs
cell of origin = interstitial cell of Cajal (pacemaker)
+ for c-kit (CD117) mutation in transmembrane receptor tyrosine kinase (RTK)
