Overview of GIT Pathology (GIT)

Question 1

What are the four general tissue layers of the GIT?

Answer 1

• Mucosa
• Submucosa
• Muscularis externa
• Serosa (visceral peritoneum)

Question 2

What is the term for ‘blood in vomit’?

Answer 2

Haematemesis

Question 3

What are the three forms of blood in stool?

Answer 3

Melaena = dark blood in stool, indicating proximal, slow bleed

Haematochezia = bright red blood in stool, indicating distal or large bleed.

Occult blood = not visible

Question 4

What tissue types can dysplasia occur in in the GIT?

How likely is it to progress to malignancy?

Answer 4

Dysplasia can occur in squamous or glandular epithelium

Dysplasia can progress to malignancy, but it is uncommon. At the same time, not all malignancy comes from dysplasia.

Question 5

How is dysplasia graded?

Answer 5

Based on degree of nuclear atypia and architecture.

Atypia = large, irregular, hyperchromatic nuclei

Low graded = low atypia, mitoses at basal layer

High graded = severe atypia, mitoses at all layers

Question 6

Differentiate between adenoma and dysplasia

Answer 6

Adenomas are benign epithelial neoplasms. They mave malignant potential and show dysplasia. However, they may not.

At the same time, dysplasia does not make a lesion an adenoma.

Question 7

What is meant by ‘atresia’ and ‘fistula’?

Answer 7

Atresia = closes off where it’s not supposed to (e.g. oesophagus)

Fistula = connects to somewhere it’s not supposed to (e.g. oesophagus joining to trachea)