Session 5 - Disorders of the Stomach Flashcards
Name four common disorders of the stomach
- Gastritis
- Gastric/duodenal ulceration
- Gastric cancer
- Gastro-oesophageal reflux disease
What is the main symptom of gastric/duodenal ulceration?
• Upper abdominal pain
Give three complications of gastric/duodenal ulceration
- Bleeding
- Perforation
- Gastric outlet obstruction
What is gastritis?
- Mucosal inflammation
* Mucosal breakdown
What is GORD?
• Anti-reflux mechanism fail and there is prolonged contact of gastric juices with lower oesoophageal mucosa
Give four physiological adaptions designed to prevent reflux
- Lower oesophageal sphincter – which is usually closed and transiently relaxes as part of physiology of swallowing to allow bolus to move into stomach
- Oesophagus enters stomach in abdominal cavity
- Pressure in abdominal cavity is higher than that of thoracic
- Right crus of diaphragm acts as sling around the lower oesophagus
Give a clinical feature of GORD
• Dyspepsia
○ Worse on lying down, bending over and when drinking hot drinks
How is GORD investigated?
- Clinical diagnosis made on history alone
* Investigations used if dyshagia present or hiatus hernia suspected
What are two overarching methods of managing GORD?
- Lifestyle
* Medication
Give three changes in lifestyle which can prevent GORD
- Lose weight
- Stop smoking
- Reduce alcohol intake
- Reduce consumption of aggravating foods
Give four medications which can be used to medicate GORD
- Simple antacids (CaCO3)
- Raft antacids (Gaviscone, creates protective raft which sits on top of stomach contents to prevent reflux
- PPI
- H2 antagonist
Give a complication of GORD
- Barrets-oesophagus
* Stratified squamous cells -> Gastric cells
Why do anti-cholinergics increase risk of GORD?
• Relax LOS
What proportion of population over 50 have gastric leiomyoma?
• 50%
What is a gastric leiomyoma?
• Benign tumour which is often accidentally discovered
What is the frequency of gastric carninoma?
• 15/100,000
What are the main symptoms of gastric carcinoma?
• Abdominal pain
• Weight loss
• NAV (nausea, vomiting, anorexia)
Anaemia
How is gastric carcinoma diagnosed?
- Endoscopy
* Barium meal
What are two types of gastric carcinoma?
- Glandular adenocarcinoma
* Diffuse, spreading type adenocarcinoma
What is chronic gastritis?
• Chronic inflmmation of stomach lining
What is a key symptom of chronic gastritis?
• pernicious anaemia
How does pernicous anaemia come about as a result of chronic gastritis?
- Loss of parietal cells
- Less intrinsic factor
- Less absorption of B12 (needs intrinsic factor)
- Down with RBC
What is peptic ulcer disease?
• A break in superficial epithelial cells penetrating down into muscularis mucosa of either stomach or duodenum
Where are duodenal ulcers usually found?
• In duodenal cap
Where are gastric ulcers usually found?
Lesser curvature of the stomach
Why are gastric ulcers usually found in less curvature of the stomach?
- More contact with irritants
* More exposure to ulcerogenic refluxed acid
What is a peptic ulcer?
• Gastric ulcers are exclusively stomach related
Peptic ulcers can be stomach related, but are predominantly duodenal
Give the two leading causes of peptic ulcers in the developed world
- H pylori
* NSAIDS
How do non-steroidal anti-inflammatory drugs cause peptic ulcers?
- Inhibits cox-1, enzyme response for conversion of arachidonic acid to prostaglandin
- Prostaglandins produce protective unstirred layer of mucus This is lost with NSAID use
What % of patients have duodenal ulcers at somepoint in their lives?
15%
How many times more common are duodenal ulcers than gastric?
• 4:1 times
Give general symptoms of peptic ulcers
- Recurrent, burning epigastric pain
- Nausea
- Vomiting
How does the diagnosis of duodenal ulcers differ from gastric?
- Duodenal ulcers - Pain worse at night and when hungry, relieved by eating
- Gastric ulcers - Pain caused by eating food
What can occur after a long period of time with a gastric ulcer
• Ulcer can perforate blood vessels, causing haematamesis (vomiting of blood)
What can the clinical features of gastric ulcers be confused for?
• Gastric carcinoma
Outline three investigations for suspected peptic ulcers
- Investigate H. Pylori
- Endoscopy
- Barium meal
What is the management of peptic ulcer disease?
• If due to H pyloiri infection, triple therapy
Review NSAID use
What is a major complication of peptic ulcer disease?
- Iron defiency anaemia due to acute GI bleed
- Haematmesis and melena
- Perforation into peritoneal cavity
Gastric outlet obstruction
Where can a gastric obstruction be present?
Where can a gastric obstruction be present?
• Pre-pyloric, pyloric or duodenal
What is gastric obstruction as a result of peptic ulcer due to?
• Oedema with active ulcer
Fibrosis of ulcer
What does persistent penetrating pain from peptic ulcer indicate?
• Penetration of ulcer to other organs
What is H pylori?
- Bacteria - Gram negative
- Motile, aerobic
- Urease producing
- Adheres to gastric mucosa
- Produces cytotoxins
- Strong association with gastritis
How do H pylori survive the acidic conditions of the stomach?
• Production of urease produces ammonia, which neutralises acidic environment which allows bacterium to survive
How is H pylori diagnosed?
- IgG detected in serum (good sensitivity and specificity)
- 13C-urea breath test
- Gastric sample by endoscopy and detect by histology and culture
What is the 13Curea-breath test?
- 13Curea ingested - If H.pylori present the urease produced will break down 13C-urea to NH3 and CO2
- Carbon 13 will be detected in CO2 on exhalation
Give one thing other than helicobacter pylori which causes gastric ulceration
• NSAIDS
Outline the treatment for Helicobacter pylori
• Triple therapy
○ PPI - omeprazole
○ Two antibiotics - Clarithomycin/amoxicillin
○ H2 anatagonist
How effective is standard eradication therapy of H. Pylori?
• 80-90% chance of eradication
Outline three diseases which H.pylori increase risk of
- Gastritis
- Peptic ulcer disease
- Gastric disease
What does chronic gastritis cause?
• Hypergastrinaemia due to gastrin release from astral G cells -> This increased acid production is usually asymptomatic, but can lead to duodenal ulceration
What factors are implicated in the development of duodenal ulcers in people with H.pylori
• Genetic predispositions, bacterial virulence, increased gastrin secretion and smoking
How does H. Pylori cause peptic ulcers?
• Causes elevated levels of gastrin due to G-cell hyperplasia, predisposing to gastric ulceration
Less HCO3- produced, lives in mucus
Give two ways in which acid secretion may be reduced by drugs
• H2 antagonists
PPI
