Metaplasia part 2 Flashcards
What suggests that stem cells are involved in BM?
All 5 intestinal differentiated cell types are found in BM
Which stomach cells produce acid?
Parietal cells
What can happen if the lower esophageal sphincter relaxes?
Acid from the stomach can go up and enter the oesophagus
What can stomach acid do to cells of the oesophagus?
Irritate them, and eventually destroy them
What happens once enough destruction of SSQE cells in the oesophagus occurs?
They are eventually replaced by columnar epithelium
How does acid reflux manifest itself?
Heartburn
What are the mechanisms of increased acid reflux?
Increased rate of lower esophageal relaxation
Increased intragastric pressure
Increased acid production
What can lead to increased rate of lower esophageal relaxation?
Diet–> consumption of alcohol, chocolate, peppermint, coffee etc
Smoking
What can cause increased intragastric pressure?
Obesity–> increased fat pushes on lower esophageal sphincter
What can cause increased stomach acid production?
Eating a fatty rich meal–> stays in stomach for longer so more acid
How is BM diagnosed?
Endoscopy and confirmation of presence on a biopsy by a pathologist
What is an endoscopy?
Put a camera down into the oesophagus to look at the lining
Which stains are used in a BM biopsy?
Haematoxylin and eosin
Diff between UK and US BM definition?
UK–> appearance of columnar-like epithelium
US–> appearance of goblet cells
Endoscopy observations to possibly diagnose BM?
Change in colour of the oesophagus–> more red (normal is salmon pink)
Where can an adenocarcinoma spread out to?
The esophageal lumen, and the wall
What molecule does an alcian blue stain indicate?
Mucopolysaccharides
What cells are mucopolysaccharides present in?
Giblet cells
Disease progression of BM to adenocarcinoma?
Normal–> BM–> Dysplasia–> oesophageal adenocarcinoma
What is dysplasia?
Abnormal growth and differentiation of a tissue
What is GORD?
Gastro-Oesophageal Reflux Disease
What % of westerners have GORD?
20%
What % of GORD patients develop MB?
3-5%
What % of BM patients develop oesophageal adenocarcinoma?
3%
What is the mortality rate of esophageal adenocarcinoma at 12 months post diagnosis?
60%
Main BM treatments?
H+ pump inhibitors
Radiofrequency ablation
Cancer treatment if AC
Removal of BM section–> pull down top of oesophagus to meet stomach
What is an example of a proton pump inhibitor?
Omeprazole
Which BM treatment is given first?
H+ pump inhibitors
How do H+ pump inhibitors work?
Inhibit the secretion of H+ from the parietal stomach cells
What is radiofrequency ablation?
One electrode on hip, one on the BM tissue. Run a current through the it
Columnar cells are destroyed via heating of the electrodes
