Stomach Path

Question 1

What cells is the body of the stomach composed of?

Answer 1

foveolar cells that secrete protective mucus

glands w/ parietal cells (secrete HCl) and chief cells (secrete pepsin)

Question 2

What cells is the antrum of the stomach composed of?

Answer 2

G cells producing gastrin - promotes secretion of HCl and pepsin

Question 3

What are internal and external injurious agents to the stomach?

Answer 3

internal - pepsin, HCl, bile

external - drugs, alcohol, bacteria

Question 4

What are the defensive forces of the stomach?

Answer 4

mucus, bicarb, cell regeneration, blood flow, prostaglandins

Question 5

What does the tern “gastritis” refer to?

Answer 5

any inflammation, ulceration/erosion, irritation

Question 6

What are the symptoms of gastritis?

Answer 6

nausea, abdominal bloating, heartburn, hiccups, epigastric pain, bleeding with possible hematemesis and melena, coffee ground emesis

Question 7

What are the histologic features of chronic gastritis?

Answer 7

lymphocytes and plasma cells in lamina propria
with or without ACTIVITY (inflammation - PMNs)
can destroy parietal cells and glands –> metaplasia

Question 8

What features are present with chronic gastritis due to H. Pylori?

Answer 8

both active and chronic gastritis

T and B lymphocytes, then infiltration of lamina propria and epithelium by neutrophils

Question 9

What feature is H. pylori gastritis known for producing?

Answer 9

lymphoid follicles and germinal centers

Question 10

What is different about the features of autoimmune gastritis as opposed to that caused by H. pylori?

Answer 10

NO active inflammatory component with neutrophils

Question 11

How does H. pylori colonize the stomach?

Answer 11

uses flagella to burrow into mucus and reach niche close to epithelial layer
senses acidic pH of lumen by chemotaxis and swims away
adhesins help it adhere to epithelial cells

Question 12

How does H. pylori damage the stomach?

Answer 12

produce urease that breaks down urea to carbon dioxide and ammonia –> ammonium that neutralizes gastric acid, allowing survival
ammonia and other products are toxic to epithelial cells

Question 13

How can H. pylori be detected?

Answer 13

CLO test - if it turns red indicates pH change - means H. pylori

Question 14

What antibodies are present in autoimmune chronic gastritis?

Answer 14

anti-intrinsic factor

anti parietal cell

Question 15

What are the two patterns of H. pylori associated chronic gastritis?

Answer 15

diffuse antral - chronic inflammation w activity - in individuals w peptic ulcers
multifocal atrophic - gastric atrophy and partial replacement by intestinal epithelium - individuals who dev gastric carcinoma and ulcers

Question 16

What is the treatment for H. pylori?

Answer 16

antibiotics plus acid suppressants

PPIs

Question 17

What are possible complications of H. pylori?

Answer 17

gastric or duodenal ulcers

increased risk of gastric adenocarcinoma and lymphoma (MALT)

Question 18

What are the consequences of AIG (autoimmune gastritis)?

Answer 18

destruction of parietal cells and eventual replacement of normal gastric mucosa by intestinal metaplasia and fibrosis
decreased intrinsic factor –> dec B12 –> pernicious anemia
hyperplasia of G cells –> hypergastrinemia - trophic effect on ECL cells that can transform into carcinoid tumors
inc risk of adenocarcinoma

Question 19

What is seen microscopically in acute gastritis?

Answer 19

superficial neutrophilic infiltrates (above BM), mucosal edema, reactive and regenerative changes of surface epithelium, maybe erosions

Question 20

What is acute erosive gastritis?

Answer 20

acute gastritis with necrosis of epithelial cells

Question 21

What is the pathogenesis of acute gastritis due to?

Answer 21

compromise of mucosal defenses

increased acid production/decreased bicarb production

Question 22

What agents are associated frequently with acute gastritis?

Answer 22

heavy NSAID use, excessive alcohol, smoking, severe physical stress, chemo/radiation, bile reflux from duodenum, iron pills

Question 23

What are the clinical features of acute gastritis?

Answer 23

mild epigastric discomfort to hematemesis, melena and potentially fatal blood loss

Question 24

What is an ulcer?

Answer 24

breach of gastric mucosa that extends through muscularis mucosa into submucosa or beyond

Question 25

What are the most common causes of gastric or duodenal ulcers?

Answer 25

increased acid/pepsin secretion H. pylori NSAIDs

Question 26

Where in the stomach and duodenum do ulcers typically occur?

Answer 26

stomach - lesser curvature and antrum | duodenum - first part

Question 27

What are peptic ulcers?

Answer 27

can be gastric or duodenal single sharply punched out defects with clean base due to peptic digestion of necro-inflammatory debris flat rim (unlike rolls in cancer) usually chronic gastritis in adjacent mucosa

Question 28

What are the four zones of a chronic active ulcer?

Answer 28

necrotic fibrinoid debris mixed acute and chronic inflammation granulation tissue fibrosis/scar

Question 29

What two conditions are key for the dev of most peptic ulcers?

Answer 29

H. pylori inf | mucosal exposure to gastric acid and pepsin

Question 30

What is the difference between duodenal and gastric ulcers?

Answer 30

duodenal have increased gastrin and acid levels | gastric have normal or reduced gastric acid production

Question 31

What is the major cause of PUD in people who are heliobacter negative?

Answer 31

NSAIDs - inhibit COX1 that produces a prostaglandin that protects stomach lining

Question 32

What are risk factors for NSAID-related gastroduodenal toxicity?

Answer 32

older age higher doses prolonged use

Question 33

What is the relationship between ulcers and cancer?

Answer 33

cancers often ulcerate but ulcers rarely become malignant (never with duodenal and rarely with gastric)

Question 34

What are complications of PUD?

Answer 34

GI bleeding Perforation - can penetrate into adjacent organ Gastric outlet obstruction - inflammation or scar formation in outlet area

Question 35

Where do duodenal ulcerates vs. gastric ulcers penetrate?

Answer 35

duodenal - posteriorly into pancreas | gastric - into left hepatic lobe

Question 36

What are signs and symptoms of gastric outlet obstruction?

Answer 36

early satiety, nausea, vomiting, postprandial abdominal pain, weight loss

Question 37

What are stress ulcers?

Answer 37

usually multiple and shallower than peptic ulcers - don't penetrate muscularis propria heal w no fibrosis or scarring in stomach mostly

Question 38

What conditions are stress ulcers seen in?

Answer 38

severe trauma use of gastric irritant drugs (NSAIDs, corticosteroids) extensive burns (Curling ulcers) CNS trauma (Cushing ulcers)

Question 39

What are the main causes of peptic ulcers?

Answer 39

H. pylori NSAIDs, corticosteroids Zollinger Ellison syndrome

Question 40

What are the types of gastric tumors?

Answer 40

adenocarcinoma MALT lymphoma Carcinoid

Question 41

What are the symptoms of gastric malignancies?

Answer 41

nausea, vomiting, early satiety, GI blood loss | iron deficiency anemia