Peptic Ulcers

Question 1

What are peptic ulcers?

Answer 1

Erosions of the mucosa which extend at least into the submucosa

Question 2

Peptic ulcers are the result of an imbalance between gastric secretions and protective mucosal factor. What can be the cause of this imbalance?

Answer 2

H.pylori infection
Zollinger ellison syndrome
Long term NSAID use
Stress ulceration

Question 3

What type of bacteria are h.pylori?

Answer 3

Gram negative rod shaped

Question 4

How are h.pylori bacteria able to survive in the acidic environment if the stomach?

Answer 4

Flagella allow them to move and burrow into the stomach’s protective mucosal layer and take residence here.
H.pylori have the enzyme urease which converts urea (from the breakdown of protein) it ammonia and carbon dioxide, the ammonia can act as a buffer to neutralise the stomach acid in the vicinity of the bacteria.

Question 5

In the western world, how prevalent is h.pylori infection?

Answer 5

50% of over 50s are infected

Question 6

How can h.pylori infection lead to the formation of peptic ulcers?

Answer 6

H.pylori releases exotoxins - vacA induces apotosis of stomach cells and CagA disrupts the cell integrity and stricture and causes inflammation. The damage caused to the stomach epithelium allows hydrochloric acid to come into contact with the stomach cells and start to erode these cells.

Question 7

How can zollinger ellison syndrome lead to the formation of peptic ulcers?

Answer 7

Zollinger ellison syndrome is a rare condition in which there is a gastrin secreting gastrinoma. This cancer will result in the cknstant secretion of gastrin and thus the increased secretion of HCL leading to an imbalance kf gastric secretion and mucosal protection and allowing peptic ulcers to form

Question 8

How does the prolonged use of NSAIDs lead to the formation of peptic ulcers?

Answer 8

NSAIDs block COX to prevent inflammation. However, since COX also has a role in producing prostaglandins which have a role in GI mucosal protection via mucous production, NSAIDs will inhibit gastric mucosal protection by mucous causing an imbalance between mucosal protection and gastric secretions and allowing peptic ulcers to form.

Question 9

Peptic ulcers are more common in the stomach than in the duodenum. T/F?

Answer 9

False the opposite is true

Question 10

What percentage of gastric leotic ulcers are caused by h.pylori infection?

Answer 10

70%

Question 11

What percentage of duodenal peptic ulcers are caused by h.pylori infection?

Answer 11

95-100%

Question 12

Is long term NSAID use more likely to result in a gastric or duodenal peptic ulcer?

Answer 12

Gastric peptic ulcer

Question 13

Other than h.pylori infection and long term NSAID use what are the risk factors for peptic ulcer disease?

Answer 13

Smoking
Increasing age
Alcohol use
Psychological stress
ABO blood group
Family history of the disease

Question 14

Epigastric pain is the main presenting symptom of peptic ulcer disease. What differences are there in this pain between duodenal and gastric peptic ulcers?

Answer 14

Gastric ulcers tend to worsen with food and so can also present with weight loss
Duodenal ulcers tend to mostly cause symptoms at night or on an empty stomach and get better with eating so may also present with weight gain

Question 15

Other than epigastric pain, what other symptoms might peptic ulcer disease present with?

Answer 15

Nausea
Heartburn
Anorexia
Vomiting

Question 16

What are the possible complications of peptic ulcer disease?

Answer 16

Haemorrhage - as a result from damage to surrounding arteries
Perforation causing escape of potent gastric contents into the abdominal cavity

Question 17

What type of antibody is found in a positive h.pylori serum test?

Answer 17

H.pylori IgG antibody

Question 18

Describe the biochemical basis of the biopsy urease test for h.pylori bacteria.

Answer 18

The biopsy sample is placed in a prepared urea solution which also contains a colour reagent. If h.pylori is present, then urease enzyme from the bacteria will react with the urea to produce ammonia and carbon dioxide. The ammonia will react with the reagent ti produce a colour change and thus indicate the presence if h.pylori.

Question 19

Describe the urea breath test for peptic ulcers?

Answer 19

Heavy carbon containing urea is given orally to the patient and in the presence of h.pylori it will be broken down into ammonia and carbon dioxide. This carbon dioxide will then contain heavy carbon and will be transported into the blood to the lungs where it is expelled. The breath is then measured for the presence of the heavy carbon which will indicate the presence of h.pylori. This is often used to determine if h.pylori has been successfully eradicated

Question 20

What percentage of peptic ulcers are healed within four weeks of therapy with histamine receptor antagonists?

Answer 20

87-94%

Question 21

How do histamine receptor antagonists work to treat peptic ulcers?

Answer 21

These block the H2 histamine receptor on parietal cells so that the parietal cells cannot be stimulated to secrete HCL by histamine

Question 22

Cinetidine, ranitidine and famotidine are all drugs used to treat peptic ulcers. What is the action of these drugs?

Answer 22

They are H2 histamine receptor antagonists

Question 23

Give examples of proton pump inhibitors.

Answer 23

Omeprazole
Lansiprazole
Pantoprazole
Rabeprazole

Question 24

How do proton pump inhibitors work to treat peptic ulcers?

Answer 24

These block the proton pump which actively transports hydrogen out of parietal cells and into the gastric lumen, there y preventing the secretion of HCL

Question 25

Proton pump inhibitors are ingested orally and have a short half life. T /F?

Answer 25

True

Question 26

Proton pump inhibitors are generally considered safe drugs but what are some of the concerns regarding their use?

Answer 26

Concern that they may reduce the absorption kf vitamin B12, iron and calcium though this is not clinically proven
They can increase the risk of enteric infections such as salmonella
They can in a very small number of cases increase the risk of osteoporosis
They can have idiosyncratic side effects such as lymphatic collitis, interstitial nephritis and hypomagnesaemia

Question 27

What drugs can be used to treat peptic ulcers?

Answer 27

Antibiotics
Proton pump inhibitors
Histamine receptor antagonists

Question 28

When a patient has peptic ulcers cause by h.pylori infection, triple therapy is used to treat them. What does this involve?

Answer 28

The use of a proton pump inhibitor and two of either amoxicillin, clarithromyocin and metronidazole. Within a week this clears 80% of cases

Question 29

Occasionally prostaglandin analogues can be used alongside NSAIDs to reduce mucosal ulceration. Five an example of these?

Answer 29

Misoprostil