Histo: Upper GI Disease Flashcards
What is a key histological feature of the oesophageal mucosa?
Presence of submucosal glands
what is the Z-line?
The point in the oesophagus at which the epithelium transitions from being squamous to being columnar
What does the cell types does the body and fundus of the stomach have in abundance?
Specialised glands responsible for producing acid and enzymes
- Parietal cells - produce HCL and IF
- Chief cells - produce pepsinogen and gastric lipase
Which part of the stomach tends to be affected by H. pylori-associated gastritis?
Pylorus and antrum
What are the three layers of the gastric mucosa?
- Columnar epithelium
- Lamina propria
- Muscularis mucosa
Describe the structure of the duodenal mucosa
Intestinal type epithelium - glandular epithelium with goblet cells
Villous architecture
What is the normal villous: crypt ratio?
2:1
What does the presence of goblet cells in the stomach signify?
Intestinal metaplasia
NOTE: goblet cells are NOT normally seen in the stomach
What is the most common cause of oesophagitis
Reflux oesophagitis/GORD
What is the characteristic histological feature of acute oesophagitis?
Presence of lots of neutrophils
What can acute oesophagitis result in?
- Ulceration
- Fibrosis
- Haemorrhage
- Perforation
- Stricture
- Barrett’s oesophagus
Define Barrett’s oesophagus.
Metaplastic process by which the normal sqaumous epithelium of the lower oesophagus is replaced by columnar epithlieum
NOTE: this is also known as columnar-lined epithelium (CLO)
What are the 2 types of oesopahgeal metaplasia in Barrett’s
- Gastic metaplasia: no goblet cells
- Intestinal metaplasia: with goblet cells (associated with increased risk of cancer)
NOTE: metaplasia is reversible
Define dysplasia.
Changes showing some of the cytological and histological features of malignancy but with no invasion through the basement membrane.
What is adenocarcinoma of the oesophagus associated with and which part does it affect?
- Associated with reflux
- Affects lower 1/3 of oesophagus
- Most common type of oesophageal cancer in developed countries
Describe the main histological feature of oesophageal adenocarcinoma
Moderate to well-differentiated, mucin producing glands (intestinal type mucosa)
Usually adjacent regions of Barrett’s present
What is squamous carcinoma of the oesophagus associated with and which part does it affect?
- Smoking and alcohol
- It tends to affect the upper 2/3 of oesophagus
- It is the most common type of oesophageal cancer in developing countries
What are the main histological features of squamous cell carcinoma of the oesophagus?
Cells produce keratin (normal oesophageal squamous epithelium is non-keratinised)
Intercellular bridges
How is eosinophilis oesophagitis treated?
- Steroids
- Allergen removal
NOTE: this is associated with an allergic reaction (asthma of the oesophagus). It is due to allergy to food causing muscle spasm and dysphagia.
What is the commonest cause of oesophageal varices?
- Cirrhosis of the liver (Most common)
- Portal vein thrombosis
List some causes of acute gastritis
Chemical: NSAIDS, alcohol, corrosives
Infection: H pylori
List some causes of chronic gastritis
- Autoimmune (e.g. pernicious anaemia, anti-parietal cell) - affects body
- Bacterial (H. pylori) - affects antrum
- Chemical (NSAIDs, bile reflux) - affects antrum
NOTE: the key inflammatory cells in chronic gastritis are lymphocytes
What is mucosa-associated lymphoid tissue and what is their presence indicative of?
- Chronic gastritis caused by H. pylori infection induces lymphoid tissue in the stomach
- The presence of lymphoid follicles in a stomach biopsy, is highly suggestive of H. pylori infection
- This is important because it is associated with an increased risk of lymphoma
What are some complications of H. pylori gastritis
- Adenocarcinoma
- MALT lymphoma
H. pylori asscoaited with 8x increased risk of gastric cancer