B5-032 Gastric Ulcer

Question 1

main hormone produced by antral cells to stimulate parietal cells to produce acid

Answer 1

gastrin

Question 2

main inhibitor of gastric acid secretion

Answer 2

somatostatin

Question 3

main neurotransmitter secreted by vagus nerve to regulate acid secretion

Answer 3

ACh

Question 4

promotes mucus secretion

Answer 4

prostaglandin

Question 5

main risk factors for ulcers

2

Answer 5

H. pylori
NSAIDs

Question 6

how does H. pylori cause ulcers in a majority of cases?

Answer 6

pangastritis of antral and fundic mucosa, causing reduced mucous production

Question 7

how does H. pylori cause duodenal ulcers in a minority of patients?

Answer 7

causes antrum predominant gastritis which results in high gastric acid secretion

Question 8

describe the characteristics of H. pylori bacterium

gram stain, shape, etc.

Answer 8

gram negative
helical rod shape
flagellae

Question 9

major characteristics of peptic ulcer disease

Answer 9

periodic epigastric pain

(may be relieved with food or antacids)

pain occuring every 6-12 weeks, if on NSAIDs may have no pain

Question 10

imaging modality of choice to diagnose peptic ulcer disease

Answer 10

EGD

CT if perforated

Question 11

risk factors for peptic ulcer disease

4

Answer 11

• Type A personality
• steroids
• NSAIDs
• Zollinger Ellison

Question 12

mucosal protective agents

3

Answer 12

• sucralfate
• pepto-bismol
• misprostrol

Question 13

identify the image

Answer 13

gastric ulcer

Question 14

how might an ulcer present in an older person?

Answer 14

bleeding/perforation symptoms without preceding pain

Question 15

what is the diagnostic modality of choice when perforated ulcer is suspected?

Answer 15

CT scan

Question 16

what symptoms may lead you to suspect perforation?

Answer 16

severe abdominal pain
abdominal wall rigidity

Question 17

what country has a highest incidence of H. pylori?

Answer 17

China

Hong Kong specifically, may be relevant to patient’s hx

Question 18

how does H. pylori cause ulcers?

Answer 18

• causes inflammation
• activates T cells
• chronic cellular damage
• worsened by acid
• H. pylori proteins channel into gastric epithelial cells

Question 19

how do NSAIDs cause ulcers?

Answer 19

• block COX-1 from synthesizing prostaglandings
• decrease mucous barrier
• worsened by acid

Question 20

which form of gastritis is more likely to cause an ulcer in the stomach and not the duodenum?

Answer 20

pangastritis

Question 21

what kinds of cells are in the gastric antrum?

4

Answer 21

• G cells
• D cells
• mucous neck cells
• surface mucous cells

Question 22

why does antral gastritis cause duodenal ulcers?

Answer 22

decreased somatostatin causes increased gastric acid –> duodenal ulcer

Question 23

H. pylori attaches to receptors called […] in the gastric mucosa

Answer 23

Lewis antigens

Question 24

does H pylori invade gastric cells?

Answer 24

no

attaches to lewis antigen receptors

Question 25

genes within this island form a special apparatus to transport bacterial product inside the host cell

Answer 25

cag pathogenicity island

Question 26

treatment of H. pylori peptic ulcer disease | 3 things

Answer 26

* remove offending agent * acid suppression * mucosal protective agent

Question 27

why is ischemia of the stomach rarely seen?

Answer 27

heavily vascularized

Question 28

descibe the neural pathway of acid secretion

Answer 28

ACh from gastric enteric neurons -> M3 receptors -> intracellular Ca+ -> H+

Question 29

descibe the hormonal pathway of acid secretion

Answer 29

Gastrin from antral G cells -> CCK2 receptors -> intracellular Ca+ -> H+

Question 30

describe the paracrine pathway of acid secretion

Answer 30

histamine released from oxyntic ECL cells -> H2 receptors -> cAMP pathway | inhibited by somatostatin

Question 31

inhibits the paracrine pathway of gastric acid secretion

Answer 31

somatostatin

Question 32

how do PPIs block the proton pump?

Answer 32

sulfenamide binds to cysteine in HKATPase

Question 33

what is the duration of treatment for ulcers?

Answer 33

12 or more weeks

Question 34

how do you establish a refractory ulcer?

Answer 34

* ensure patient has stopped NSAIDs * ensure H. pylori is cleared * ensure patient has been compliant with treatment * counsel about smoking

Question 35

how do gastrinomas cause ulcers?

Answer 35

increased gastrin -> increased gastric acid

Question 36

how does systemic mastocytosis cause ulcers?

Answer 36

excessive histamine --> increased gastric acid production

Question 37

oncologic gastric ulcers | 3

Answer 37

* MALT lymphoma * gastric adenocarcinoma * metastatic disease (breast cancer)

Question 38

symptoms of systemic mastocytosis | associated with gastric ulcers

Answer 38

pruritis, flushing, syncope, nausea, vomiting, diarrhea, fibromyalgia

Question 39

symptoms of Churg-Strauss | associated with gastric ulcers

Answer 39

eosinophilia, asthma, peripheral neuropathy, palpable purpura

Question 40

options of surgical treatment of gastric ulcers | rare but happens, 3

Answer 40

* vagotomy * antrectomy * subtotal gastrectomy (both body and antrum) | or combination of above

Question 41

what is the main inhibitory method against acid secretion?

Answer 41

somatostatin

Question 42

H. pylori can lead to gastric ulcer in some, but duodenal ulcer in others. Why?

Answer 42

depends on if H. pylori infects the entire stomach or just the antrum

Question 43

how do NSAIDs cause gastric ulcers?

Answer 43

decreased mucous production by inhibiting COX-1 with reduced prostaglandin secretion

Question 44

what will happen when a tumor starts producing excess gastrin?

Answer 44

* the basal and maximal acid output is increased because parietal cells secrete more acid * ulcers will develop in unusual locations

Question 45

primary gastric cells that secrete acid

Answer 45

parietal cells

Question 46

neurogenic control of acid secretion

Answer 46

vagus via ACh

Question 47

primary gastric cells that secrete gastrin

Answer 47

G cell in antrum

Question 48

primary cells that secrete somatostatin

Answer 48

D cells

Question 49

primary gastric cells that secrete pepsin

Answer 49

chief cells

Question 50

primary gastric cells to secrete histamine

Answer 50

ECLs

Question 51

final common pathway to secrete acid

Answer 51

H+K+ATPase

Question 52

indomethacin is an NSAID, which blocks

Answer 52

COX-1

Question 53

COX-1 inhibitors cause

Answer 53

decreased production of prostaglandins

Question 54

multiple, recurrent ulcers in unsual locations

Answer 54

gastrinoma

Question 55

a serum gastrin level can help rule in/out | 2

Answer 55

gastrinoma Zollinger Eillison

Question 56

what can be measure to determine if a patient is unknowingly taking NSAIDs?

Answer 56

serum salicylate

Question 57

older people who take NSAIDs can develop complications of ulcer disease without

Answer 57

prior symptoms

Question 58

side effect of Pepto Bismol

Answer 58

black stools

Question 59

enzymes responsible for production of prostaglandins in the stomach

Answer 59

COX 1 & 2

Question 60

constitutively expressed in the stomach and helps in the production of mucus and maintaining the integrity of the gastric mucosa

Answer 60

COX-1

Question 61

surgery that will remove gastrin producing antral G cells

Answer 61

distal gastrectomy

Question 62

surgery to decrease the parietal cell mass but with leaves the antrum intact

Answer 62

proximal gastrectomy | **acid secretion will continue**

Question 63

what two surgical options significantly decrease acid production?

Answer 63

* vagotomy * distal gastrectomy