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57 Cards in this Set
- Front
- Back
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What are the main regions of the Stomach?
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Cardia
Fundus Body Antrum Pylorus |
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Heterotopic Pancreas
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1 cm nodules of pancreatic tissue in Gastic or Intestinal wall
usually in the antrum or pylorus regions Can become inflammed and may cause obstruction nipple-like projection, which has normal acini and ducts |
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Congenital Pyloric Stenosis
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Common Congenital abnormality
75% male - monozygotic twins have high concordance rates Associated with Turner's syndrome, Trisomy 18, and esophageal atresia projectile vomiting in second week of life, regurgitation and visible peristalsis thickened pyloric muscle - fusiform mass - 3-5 cm occludes pyloric channel treat with pyloromyotomy (split incision) |
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Acquired Pyloric Stenosis
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80% in men
due to hypertrophy of circular muscle fibers associated with antral gastritis or pyloric ulcer DDx - keep in mind neoplastic obstruction |
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Diaphragmatic hernia
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Defective closure of the diaphragm - weakness or absence of a region
abdominal contents present in thorax - stomach and small intestine may be assymptomatic or may have lethal respiratory problems very rarely acquired |
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Muscosal Secretion
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thin layer covering the lining of the stomach
much lower diffusion coefficient than water pepsin and acid are secreted through the mucus into the lumen - never contacts epithelial cells |
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Bicarbonate secretion
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epithelial cells in the stomach and duodenum secrete bicarb underneath the mucus layer, directly in contact with the epithelial cells
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Mucosal Defenses
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Epithelial Barrier - intercellular tight junctions - prevent acid from back flowing
Mucosal Blood flow - supplies oxygen bicarb, and nutrients and removes back diffused acid Prostaglandin synthesis - favor the production of mucus and bicarb inhibit parietal cell secretions vasodilation effects increase mucosal blood flow drugs than block prostaglandin synthesis (NSAIDS) cause mucosal damage and ulceration by removing this protectionew when the mucosa is breached the muscularis mucosa limits the injury healing occurs in hours to weeks |
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Gastritis
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inflamation of the gastic mucosa
gastropathy is mucosal damage without inflammation |
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Erosion vs. ulcers
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erosion - epithelial damage producing a defect in the mucosa
DOES NOT cross the muscularis ulcer - full thickness defect in the mucosa extending into the muscularis mucosa |
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Acute Gastritis
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transient inflammation
accompanied by hemorrhage into the mucosa mucosa can be sloughed off severe disease can cause significant GI bleeding |
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Pathogenesis of Acute Gastritis
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heavy use of NSAIDS
excessive alcohol consumption heavy smoking cancer Chemo Uremia Salmonellosis or CMV infection severe stress Ischemic Shock Suicide attempts NG intubation |
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Mechanisms of Acute Gastritis
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increased acid secretion with back diffusion
decreased bicarb buffer reduced blood flow disruption of the mucus layer bile acid regurg inadequate synthesis of prostaglandins |
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Morphology of Acute Gastritis
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mild - lamina propria exibits moderate edem
intact epithelium, scattered neutrophils Neutrophils above the basement membrane is ABNORMAL and indicated active inflammation Severe - muscosal damage, eroision and hemorrhage robust amounts of inflammatory infiltrate and fibrin -exudate in the fumen |
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Clinical features of Acute Gastritis
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hemorrhages - dark spots on an otherwise hyperemic mucosa or is association with an erosion
when there is erosion and hemorrhage it is termed acute erosive hemorrhagic gastritis seen in alcoholics as massive hematemesis can be assymptomatic or cause epigestric pain, nausea and vomiting with melena and fatal blood loss |
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Chronic Gastritis
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chronic inflammatory changes
epithelial metaplasia and mucosal atrophy erosions are usually ABSENT epithelial dysplasia and CIS/carcinoma may ensue |
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Pathogenesis of Chronic Gastritis
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Chronic infection of Helicobacter pylori (90% of patients)
Autoimmune - asoociated with pernicous anemia Alcohol and cigarette smoking Postsurgical - antrectomy with gastroenterstomy Obstructions, bezoars, gastric atony Radiation Crohn's disease |
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Helocobacter Pylori
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nonsporing, curvlinear gram negatic rod
its niche is the gastic mucus - has motility - produces urease (produces CO2 and NH3 which buffers the the acid) - has adhesins which bind to the Lewis B blood group antigens -has toxins CagA and VacA |
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Patterns of H. Pylori gastritis
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antral type gastritis with high acid production - elevated risk for duodenal ulcer
pangastritis followed by multifocal atrophy - low acid and high risk for adenocarcinoma |
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Noninvasive tests for H. Pylori
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serological tests for antibodies
fecal bacterial detection urea breath test |
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Invasive tests for H. Pylori
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gastric biopsy of tissue
detection by visualization of the bacteria in histologic sections, cultures, or PCR |
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Morphology of H. Pylori Gastritis
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antrum is best site for diagnostic biopsy
mucosa is red and coarse inflammatory cells thicken rugae mucosa become thin and flat with lymohocytes and plasma cells in the lamina propria active inflammation has neutrophils within the glandular and surface epithelium frequent germinal centers |
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Location of H. Pylori
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found in the superficial mucus layer
can be very pathcy and irregular silver stain is the best, but Giemsa nad HandE is fine absent from areas with intestinal metaplasia organisms may be present in foci of pyloric metaplasia and in Barett;s esophagus. |
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Clinical Features
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Chronic Gastritis causes few symptoms
Nausea, vomiting, upper abdominal discomfort advanced gastritis - causes hypochlordydric - atrophy of mucosa and parietal cell damage do not develop achlorhydria or pernicous anemia gastrin is in the usual range or moderately elevated -- development of peptic ulcer, gastric carcinoma, or gastric lymphoma |
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Autoimmune Gastritis
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less than 10% of chronic gastritis
antibodies against parietal cell ATPases, and gastrin, and IF recepter can cause hypochlorhydria or achlorhydria and hypergastrinemia some patients will get pernicous anemia there is some association to other autoimmune diseases such as Hashimoto, Addison's, and diabetes significantly increased risk for gastric carcinoma and endocrine absent antral damage |
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Reactive gastropathy
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common
related to COX inhibition and NSAIDS, bile reflux, mucosal trauma foveolar hyperplasia with loss of mucin and glandular regeneration mucosal edema and dilation of capillaries smooth muscle in the lamina propria ABSENCE of neutrophils in the epithelium |
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Peptic Ulcer
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breach in mucosa of the alimentary tract - through the muscularis mucosa
occur in the diodenum and stomach Acute gastric ulcers - severe stress or ingestion of NSAIDS occur in the duodenum, antrum, GE junction, margins if gastrojejunostomy Zollinger Ellison Syndrome - gastrin secreting neoplasm Meckel's diverticulum |
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Clinical course of Peptic Ulcers
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most often diagnosed in middle aged to older adults
relapsing and remitting course may heal spontaneously there is an increase in acid secretion but no increase in acidity |
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Duodneal Ulcers
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Rapid gastric emptying enhances acid delivery
H. pylori - enhances acid secretion, and inhibits bicarb in the duodenum favors gastric metaplasia in the duodenum have CagA positive strains with VacA toxin |
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Risk Factors for PUD
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chronic NSAIDS - suppress prostaglandins
cigarette smoking alcohol corticosteroids rapid gastric emptying ulcers more common in alcoholic cirrhosis COPD chronic renal failure and hypeerparathyroidism stress |
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Pathology of Peptic Ulcer
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sharp clean borders with punched out appearance
ulcerating malignant carcinoma usually occur within a few centimeters of pyloric ring |
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Gross Morphology
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small lesions are more likely to be erosions
over .6 cm is likely to be an ulcer size and location do not differentiate a benign from malignant ulcer |
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Classic Peptic Ulcer
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round to oveal shaped
sharply punched out defect heaping up of the margins is indicative of malignant lesions may perforate into the peritoneal cavity |
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Histology of Peptic Ulcers
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can be necrotic, chronically inflammed, and scaring, to healed tissue
active ulcers have 4 zones 1. fibrous exudate 2. inflammatory cells (PMN's) 3. granulation tissue 4. fibrotic tissue margins re-epithelialization at margin - it may be atypical, test for adenocarcinoma |
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Chronic Gastritis and PUD
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chronic gastritis
almost always associated with ulcers (duodenal most common) usually have H. pylori infections after ulcer heals, gastritis usually remains (ulcer is not connected to the progression of the gastritis) |
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Clinical features of Peptic Ulcer
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Epigastic gnawing/aching pain
-sometimes might present as a patient with iron deficiency anemia patient is worse at night and occurs a couple hours after meals in the day food and antacids make the pain better nausea, vomiting, bloating, belching, weight loss, penetrating ulcers can have penetrating pain to the back - |
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Course of Peptic Ulcers
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notoriously chronic - recurring lesions
takes 15 years to heal untreated todays therapies (H2 antagonists, pump inhibitors, antibiotics) heal in weeks |
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Complications of Peptic Ulcer Disease
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bleeding - can be life threatening
perforation in 5% of patients obstruction from edema or scarring malignant transformation does not occur with duodenal ulcers and is rare with gastric ulcers |
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Acute Gastric Ulceration
and Acute Erosive Gastritis |
from NSAIDS
Risk Factors: increasing age, hx of ulcers anticoagulation physiological stress - usually multiple, in the duodenum can be superficial to deep - are not precursors to gastric ulcers seen in patients with shock, burns, sepsis, or severe trauma curling ulcer - proximal duodenum after trauma/burns cushing ulcer - in stomach, duodenum or esophagus seen after cranial surgery caused by ischemia, vagal stimulation, hypoxia, and acidosis can be assyptomatic or have hypoxia and acidosis |
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Pathology of Acute Gastric Ulceration and Acute Erosive Gastritis
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hyperemia, neutrophils within epithelium
erosion - loss of epithelium without disruption the muscularis mucosa acute erosive gastritis - erosions and hemorrhages acute ulcers - small circular |
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Hypretrophic Gastropathy
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Giant cerebriform rugal folds
caused by hyperplasia of epithelial cells - mimics infiltrating carcinoma or lymphoma |
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Menetrier Disease
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type 1 - menetrier disease - profound hyperplasia of surface mucous with accompanying glandular atrophy
type 2 -hypertrophic gastropathy - hyperplasia of parietal and cheif cells type 3 - gastric gland hyperplasia - secondary to excessive gastrin secretion (Zollinger Elision syndrom) |
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Bezoars
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foreign bodies (commonly hair or vegetable matter)
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Caliber persistent artery varicies
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develop in the setting of portal hypertension
usually within a few cms of gastroesophageal junction - from longitudunal submucosal veins looks like nodular, tortuous elevations of the mucosa in the cardia or fundus |
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Stomach Polyps
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benign tumors
uncommon and found inceidentally must investigate histologically due to impossible visual diagnosis hyperplastic, fundic gland, peutz-Jeghers, juvenille, inflammatory, and adenoma |
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Hyperplastic Polyps
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non-neoplastic
mixture of epithelium, glands, with a lamina propria containing inflammatory cells and smooth muscle small and sessile located in atrium frequently seen in the setting of chronic gastritis no malignant potential |
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Inflammatory Polyp
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submucosal growth
fibromuscular tissue with prominent eosinophilia |
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Adenocarcinoma
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second most common tumor in the world
not so common in the US most countries see a decline in incidence and death leading cause of cancer death worldwide intestinal type - bulky tumors/glandular diffuse type - poorly differentiated |
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predisposing factors to Adenocarcinoma of the Stomach
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intestinal type - through pattern of dyplasia
diffuse - de novo origin nitrates, smoked and salted foods, pickled vegetables, lack of fresh fruit and vegetables low SES cigarette smoking chronic gastritis hypochlorhydria (predisposes to H. pylori) intestinal metaplasia type A blood Family history Hereditary Non-polyposis cancer syndrom |
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Pathology of Adenocarcinoma of the Stomach
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pylorus and antrum - over half of cases
cardia - 25% more common on the lesser curvature |
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Classification of gastric adenocardinoma
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depth of invasion - most important factor. advanced extends below the submucosa
macroscopic growth pattern - exophytic - protrusiion into lumen - flat - no obvious tumor. - excavated - shallow or deeply erosive crater. mimics ulcer with heaped up margins - diffuse pattern - broad region , see in metastatic cancer |
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Histological difference between intestinal and diffuse adenocarcinoma
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intestinal - neoplastic growth of glands permeate the walls. contain mucin vacuoles
diffuse - composed of mucous cells which normally do not form glands, and permeate the tissue. arise from the middle layer of the mucosa. forms a singlet ring conformation |
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Metastases from Gastric Adenocarcinoma
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left supraclavicular node
can spread to the liver and lungs krukenberg tumor - ovaries periumbilical subcutaneous nodules - Sister Mary Joseph nodule |
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Gastric Lymphoma
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Most common site for extranodal lymphoma
almost always B cell lymphomas of the MALT rarely Burkitt lymphomas, AIDS lymphoma, and Hodgkin lymphoma associated of H. pylori infection commonly exibit trisomy 3 and t(11, 18) genetic abnormalities |
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Morphology of Gastric Lymphoma
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monomorphic lymphocytic infiltrate in the lamina propria
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Gastrointestinal stromal tumors
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originate from the interstitial cells of Cajal (control peristalsis)
stain with cKIT and CD34 antibodies spindle type and apithelioid types |
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Morphology of GIST
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single or multiple
tumor can protrude into the lumen can have necrotic or cystic components can exibit spnidle cells, epithelioid cells or both |
