Pathology of the GI Tract- SI and Colon (3)

Question 1

what is the role of G cells in the antral glands?

Answer 1

they release gastrin to stimulate luminal acid secretion by parietal cells within the gastric fundus and body

Question 2

when is gastrin released?

Answer 2

in response to vagal and gastrin-releasing peptide (GRP) stimulation secondary to ingestion of peptides, amino acids, gastric distention, and an elevated stomach pH

Question 3

when is gastrin release decreased?

Answer 3

in response to paracrine inhibition by somatostatin and decreased stomach pH

Question 4

most gastric adenocarcinomas involve what?

Answer 4

the gastric antrum; the lesser curvature is involved more often than the greater curvature

Question 5

what nerve mediates acid stimulatory effects in the stomach?

Answer 5

vagus nerve

Question 6

what are 2 congenital abnormalities of the stomach that we discussed?

Answer 6

pyloric stenosis and ectopia

Question 7

what happens when ectopic pancreatic tissue is present in the pylorus?

Answer 7

inflammation and scarring may lead to obstruction (they can mimic invasive cancer)

Question 8

what is acute gastritis?

Answer 8

a mucosal inflammatory process; when neutrophils are present, the lesion is referred to as acute gastritis; when inflammatory cells are rare or absent, the term gastropathy is used

Question 9

where are prostaglandins found in high numbers?

Answer 9

in the gastric mucosa and gastric juice

Question 10

when are stress ulcers most common?

Answer 10

in individuals with shock, sepsis, or severe trauma

Question 11

what are curling ulcers?

Answer 11

ulcers occurring in the proximal duodenum and associated with severe burns or trauma

Question 12

what are cushing ulcers?

Answer 12

gastric, duodenal, and esophageal ulcers arising in persons with intracranial disease; they carry a high incidence of perforation

Question 13

what are 2 etiologies for chronic gastritis?

Answer 13

infection with h. pylori; autoimmune gastritis

Question 14

what is the most common cause of chronic gastritis?

Answer 14

infection with the bacillus helicobacter pylori

Question 15

what can long-standing chronic gastritis that involves the body and fundus lead to?

Answer 15

it may ultimately lead to mucosal atrophy and/or intestinal metaplasia–> both are risk factors for adenocarcinoma

Question 16

what does chronic gastritis expose the epithelium to?

Answer 16

inflammation-related free radical damage and proliferative stimuli leading to gastric dysplasia–> over time this can result in carcinoma

Question 17

how does h. pylori present? (like how does the stomach look)

Answer 17

most often presents as predominantly antral gastritis with normal or increased acid production

Question 18

what is H. pylori infection associated with in the US?

Answer 18

poverty, household crowding, limited education, african american or mexican american ethnicity, residence in rural areas, and birth outside of the US

Question 19

what is the carrier of h. pylori?

Answer 19

humans are the primary carriers, suggesting that transmission is primarily by the fecal-oral route

Question 20

what are three examples of the diagnostic tests used for H. pylori infections?

Answer 20

serologic test, fecal bacterial antigen detection, urea breath test

Question 21

what are the effective treatments for H. pylori?

Answer 21

combinations of antibiotics and proton pump inhibitors

Question 22

what is autoimmune gastritis characterized by? histologically

Answer 22

diffuse mucosal damage of the oxyntic (acid-producing) mucosa within the body and fundus

Question 23

what is autoimmune gastritis characterized by in general?

Answer 23

antibodies to parietal cells and intrinsic factor that can be detected in serum and gastric secretions; reduced serum pepsinogen I concentration; endocrine cell hyperplasia; vitamin B12 deficiency; defective gastric acid secretion (achlorhydria)

Question 24

what is progression of autoimmune gastritis like?

Answer 24

progression to gastric atrophy probably occurs over 2-3 decades, and anemia is seen in only a few patients; because of the slow onset and variable progression, patients are generally diagnosed only after being affected for many years

Question 25

what is the median age of autoimmune gastritis diagnosis?

Answer 25

60

Question 26

what are the clinical features of autoimmune gastritis?

Answer 26

they are related to deficiency in cobalamin–> atrophic glossitis, megaloblastosis of RBCs and epithelial cells; peripheral neuropathies and subacute combined degeneration of spinal cord; malabsorptive diarrhea

Question 27

what are 3 uncommon forms of gastritis?

Answer 27

eosinophilic (allergies, immune disorders, parasites); lymphocytic (varioliform gastritis)- women, celiac disease; granulomatous- crohn disease most common

Question 28

PUD results from what?

Answer 28

imbalances between defense mechanisms and damaging factors that cause chronic gastritis

Question 29

nearly all peptic ulcers are associated with what?

Answer 29

H. pylori infections, NSAIDs, or cigarette smoking

Question 30

what are the complications associated with PUD?

Answer 30

bleeding (iron deficiency anemia or hematemesis), perforation, obstruction (acquired pyloric stenosis) mucosal atrophy and intestinal metaplasia, dysplasia, gastritis cystica

Question 31

how are peptic ulcers described morphologically?

Answer 31

round to oval, sharply punched out defect- the mucosal margin may overhang the base slightly, particularly on the upstream side, but it is usually level with the surrounding mucosa

Question 32

heaped up margins of peptic ulcers are characteristic of what?

Answer 32

cancers

Question 33

hypertrophic gastropathies are characterized how?

Answer 33

by giant cerebriform enlargement of the rugal folds due to hyperplasia without inflammation

Question 34

What are two examples of hypertrophic gastropathies?

Answer 34

menetrier disease and zollinger-ellison syndrome

Question 35

what are the symptoms associated with menetrier disease?

Answer 35

hypoproteinemia, weight loss, and diarrhea

Question 36

what are the symptoms associated with zollinger-ellison syndrome?

Answer 36

peptic ulcers

Question 37

what are the risk factors for menetrier disease?

Answer 37

none

Question 38

what are the risk factors for zollinger-ellison syndrome?

Answer 38

Multiple endocrine neoplasia

Question 39

which hypertrophic gastropathy is associated with adenocarcinoma?

Answer 39

menetrier disease