Treatment of Peptic Ulceration and Inflammatory Bowel Disease Flashcards
What are some of the protective mechanisms required due to gastric acid
Mucous secreting cells - Trap bicarbonate ions and create a gel like barrier.
Prostaglandins - stimulate secretion of mucus and bicarbonate, dilate mucosal blood vessels and are cytoprotective
Explain how the proton pump is involved in the secretion of hydrochloric acid by the gastric parietal cells
It pumps hydrogen ions from within the parietal cell out into the lumen where it can combine with chloride ions to form hydrochloric acid. Therefore inhibition of this pump can reduce the amount of hydrochloric acid produced.
Name three endogenous secretagogues agents
1) Gastrin - Stimulates secretion of acid by parietal cells through proton pump.
2) Acetylcholine - Stimulates muscarinic receptors on surface of parietal cells and histamine containing cells.
3) Histamine - Acts on parietal cell H2 receptors
What are some of the associations of helicobacter pylori
- Causative factor in gastric and duodenal ulcers,
- Risk factor for gastric cancer,
- Strong link with MALT lymphoma
Explain the acute infection caused by helicobacter pylori
It tends to last about two weeks giving symptoms of nausea, dyspepsia malaise and halitosis. Gastric mucosa inflamed with neutrophils and lymphocyte penetration
Describe features of chronic infections caused by H.pylori
- Local inflammation and gastritis.
- Outcome depends on pattern of inflammation, host response, bacterial virulence, environmental factors and patient age.
What are some non-invasive and invasive diagnostic tests for helicobacter pylori infection
NI - Urea breath test, stool antigen.
I - Rapid urease test (CLO test)
What are indications for the use of proton pump inhibitors and the most common examples
Lansoprazole and omeprazole.
- H.pylori infection,
- Peptic ulcer disease,
- Dyspepsia,
- GORD,
- Treat/prevent NSAID associated ulcers,
- Reflux oesophagitis,
- Zollinger-Ellison syndrome
What are some of the unwanted side effects of proton pump inhibitors
Headaches, Diarrhoea, rashes, dizziness, somnolence, confusion, impotence, gynaecomastia, pain in muscles/joints. May mask symptoms of gastric cancer
Describe features of histamine H2 receptor antagonists and name some examples
Ranitidine and Cimetidine. They inhibit histamine, gastrin and ACh acid production. It is clinically used for peptic ulcers and reflux oesophagitis
What are some of the possible side effects of histamine H2 receptor antagonists?
Diarrhoea, dizziness, muscle pains, alopecia, transient rashes and hypergastrinaemia.
Cimentidine - Interact with androgen receptors causing gynaecomastia and decreased sexual function. Inhibits cytochrome P450 (slows metabolism)
Explain the difference between dyspepsia and Gastro-Oesophageal Reflux Disease (GORD)
Dyspepsia - Pain or discomfort centred in upper abdomen exacerbated by food.
GORD - Acid reflux associated with waterbrash (stomach acid gets in your throat)
What is the first line advice to give patients with dyspepsia/GORD
Lifestyle advice - healthy eating, weight reduction and smoking cessation.
Avoid known precipitants - Alcohol, coffee, chocolate and fatty foods.
Raise the head of the bed and have a main meal well before going to bed
What are the types of medication which can be used in the treatment of dyspepsia and GORD
- Stop NSAIDs where appropriate.
- Consider OTC; Antacids (directly neutralize acid and inhibit activity of peptic enzymes), Alginates (increases viscosity and adherence of mucus oesophageal mucosa), Simeticone (antifoaming agent, which helps bloating)
Explain the pathogenesis of peptic ulcers
It is an imbalance between mucosal-damaging (acid and pepsin) and mucosal protecting factors(mucus, bicarbonate, prostaglandins and nitric oxide).
