Week 5 - Pathophysiology Of Gastric Disease Flashcards
What is dyspepsia?
Heart burn/indigestion for 3 or more months
What is gastro-oesophageal reflux disease (GORD)?
Reflux of stomach contents into oesophagus
What are the symptoms of GORD?
Heartburn
Cough
Sore throat
Disphagia
What are the main causes of GORD?
Lower esophageal sphincter problems
Delayed gastric emptying
Hiatus hernia
Obesity
Why does delayed gastric emptying cause GORD?
Because it causes raised intra-gastric pressure
What is a hiatus hernia?
Lower esophageal sphincter goes into thorax
What Robles does GORD cause?
Oesophagitis
Strictures
Barrett’s oesophagus
What is Barrett’s oesophagus?
Metaplasia of squamous epithelium of oesophagus to columnar
What complications may occur due to Barrett’s oesophagus?
Adenocarcinoma
How is GORD treated?
Lifestyle modifications
Pharmacologically - antacids, H2 antagonists, proton pump inhibitors (PPIs)
Surgery (rare)
What surgery is performed to treat GORD?
Wrap fundus of stomach around to support lower oesophageal sphincter
What is acute gastritis?
Acute mucosal inflammation of stomach
What may cause acute gastritis?
Heavy use of NSAIDs
Lots of alcohol - dissolves mucous layer
Chemotherapy - affects highly proliferating cells
Bile reflux
What are the symptoms of acute gastritis?
Asymptomatic or Pain Nausea Vomiting Occasionally bleeding - may be fatal
What may cause chronic gastritis?
Bacterial - H-Pylori (most common cause)
Autoimmune - antibodies to gastric parietal cells
Chemical/reactive - chronic alcohol abuse, NSAIDs, reflux of bile
What would the symptoms of chronic gastritis caused by H-pylori be?
Asymptomatic or similar to acute gastritis
Other symptoms may develop due to complications such as peptic ulcers and adenocarcinoma
Why might complications with chronic gastritis occur?
Not as protective against acid as mucous secreting cells are inflamed
What would the symptoms of chronic gastritis caused by autoimmune response be?
Symptoms of Angelia, gloss it is (inflammation of tongue), anorexia, neurological symptoms
What are peptic ulcers?
Defects in gastric/duodenal mucosa extending though the muscular is mucosa
Were are peptic ulcers most commonly found?
Most commonly in first part of duodenum
Also commonly found in lesser curve of stomach
What is the cause of peptic ulcers?
Mucosal injury due to stomach acid, H-pylori, NSAIDs, smoking (only really contributes to relapse of ulcer disease), massive physiological stress e.g. Burns
What are the symptoms of peptic ulcers?
Epigastric pain - burning/gnawing pain Following meal times if stomach At night if duodenal Bleeding/anaemia Satiety early (feeling full) Weight loss
What is functional dyspepsia?
Symptoms of ulcer disease but no physical evidence
How can H-pylori be detected?
Urease breath test
How does a urease breath test work?
H-pylori breaks down urea which increases surrounding pH
Give patient radiolabel
If CO2 given off on breath the H-pylori present
How are peptic ulcers treated?
Eradicate H-pylori - PPI, clarithromycin, amoxicillin
Stop NSAIDs
Endoscopy for bleeding ulcers
PpIs
What are the most common H2 blockers used?
Cimetidine
Ranitidine
What is the he most common proton pump inhibitor?
Omeprazole
How is H-pylori spread?
Oral to oral
Faecal to oral
Describe what type of bacteria H=pylori is?
Helix shaped
Gram negative
Microaerophillic
What does urease do?
Converts yea to ammonium which is basic in solution so increases the local pH around the bacteria
How does the H-pylori cause problems?
Releases cytotoxins
Expresses enzymes
Possibly degrades mucous layer
Promotes inflammatory response
How does promoting an inflammatory response cause injury?
Causes self injury
How do cytotoxins cause damage?
Direct epithelial injury
Where in the stomach is H-pylori usually found?
The antrum
If H-pylori are colonising the antrum and the body of the stomach what will the symptoms be?
Asymptomatic
If H-pylori is only colonising the stomach what will the symptoms be?
Its where most of the G cells are located so there will be an increase in gastrin secretion which will cause increase in parietal cells acid secretion
This may cause duodenal epithelial metaplasia, colonisation of duodenum, duodenal ulceration
If H-pylori are predominantly colonising the body of the stomach what will the symptoms be?
Will have an atrophic affect cause in gastric ulcers and intestinal metaplasia which may lead to cancer
What is zollinger-ellison syndrome?
A non beta islet cell gastrin secreting tumour of the pancreas
Causes proliferation of parietal cells, this means lots of acid produced and causes severe ulceration of the stomach and small bowel
What are the symptoms of Zollinger-Ellison syndrome?
Abdominal pain, diarrhea
What may cause stress peptic ulcers?
Severe burns raised intercranial pressure Sepsis Severe trauma Multiple organ faliure
What are the symptoms of stomach cancer?
Presents late, has to be quite large before symptoms arise Diphagia Loss of appetite Malaena Weight loss Nausea Vomiting Virchow's nodes
What is melaena?
Iron in blood is oxidised causing stool to be black
What areas of the world is stomach cancer most common and why?
Chile, japan, South America
Their diets predispose them to it
What are the risk factors for stomach cancer?
Male
H-pylori
Dietary factors
Smoking
