GIT - stomach Flashcards
diseases of the stomach
congenital (2) and acquired (6)
congenital
- diaphragmatic hernia
- pyloric stenosis
acquired
- gastropathy
- acute gastritis
- chronic gastritis
- peptic ulcer (PUD)
- neoplasm
- uncommon forms of gastritis (eosinophilic, lymphocytic, granulomatous)
gastropathy definition
inflammation of gastric mucosa
absence of inflammatory cells
acute gastritis
+ symptoms
inflammation of gastric mucosa
presence of neutrophils
causes superficial erosions and gastric ulcers
cause congestion also -> petechial hemorrhage / erosions
symptoms: epigastric pain, indigestion, n/v, bleeding
may be asymptomatic also
causes of acute gastritis/gastropathy (6)
- reflux - alcohol, bile
- drugs: NSAIDs
- cigarettes
- chemo/radiation therapy
- stress-induced mucosal injury: sepsis/ trauma/ burns/ cushing’s (cause intracranial disease?)
- uremia
pathogenesis of acute gastritis/gastropathy
- NSAIDs: inhibit COX dependent synthesis of prostaglandins - prostaglandins are the one that stimulate defence mechanisms in stomach
- chemo/radiation therapy + chemicals/alcohol/cigarettes: direct injury to mucosal epithelium and stroma cells
- stress-induced mucosal injury: results in local ischemia
cushing’s cause IC disease stimulates vagal nuclei -> hypersecretion of acid - uremia: inhibits gastric bicarbonate transporters
chronic gastritis pathogenesis
Chronic mucosal inflammation -> mucosal atrophy and intestinal metaplasia
metaplasia -> carcinoma
chronic gastritis forms (2)
- associated chronic gastritis: H.pylori**
- autoimmune gastritis
H.pylori
- diseases associated (4)
most common cause of chronic gastritis
asymptomatic
diseases associated:
- Chronic gastritis
- Peptic ulcer
- Gastric carcinoma
- Gastric lymphoma
H.pylori associated chronic gastritis characteristics
- active inflammation: inflammatory cells (neutrophils, lymphocytes, lymphoid aggregates)
- regenerative changes: epithelium undergoes mitosis
- eptithelium metaplasia (now looks like intestines)
- atrophy: loss in glands
- may undergo dysplasia -> invasive adenocarcinoma
H.pylori diagnosis
- urea breath test: H/pylori produces urease which breaks down the urea -> radioactive CO2 detected in breath
CO2 detected = pos of H.pylori infection - serology
- histology
- culture: curved microaerophilic organism
autoimmune gastritis (chronic gastritis)
rarer (<10%)
- Diffuse gastritis of oxyntic mucosa (in body and fundus of stomach)
- > antibodies to gastric parietal cells and intrinsic factor can be detected in serum/gastric secretions
- extensive intestinal metaplasia and pseudopyloric metaplasia
- severe gastric body-fundal atrophy
effects of autoimmune gastritis (4)
- Defective gastric acid secretion – hypo- or achlorhyridia
- Endocrine cell hyperplasia - hypergastrinemia
associated w/ endocrine disorders: hashimoto’s/graves/DM - Disabled ileal Vit B12 absorption - Megaloblastic anemia
- Chief cell destruction - reduced serum pepsinogen I concentration
could lead to Pernicious anemia (vit B12 def), adenocarcinoma, carcinoid tumor
peptic ulcer disease (PUD)
chronic mucosal ulceration affecting the duodenum or stomach
- more common in 1st part of duodenum
- affects lesser curve of stomach
penetrates muscularis mucosae
other rarer PUD caused diseases
Heterotopic gastric mucosa - at merkel diverticulum (umbilical cord remains that cause an outpouching)
risk factors/ causes of PUD
- H,pylori
- cigarettes
- COPD
- drugs that reduce mucosal blood flow (cocaine)
- NSAIDs
- alcohol -> alcoholic cirrhosis
- psychological stress - increase gastric acid secretion
- Endocrine hyperplasia - stimulate parietal cell growth
- Zollinger-Ellison syndrome in distal duodenum
