Pathology of the Small Bowel

Question 1

What can mesenteric artery atherosclerosis and thromboembolism from the heart (AF) cause?

Answer 1

Mesenteric arterial occlusion leading to small bowel ischaemia

Question 2

What drugs can lead to non occlusive perfusion insufficiency?

Answer 2

Cocaine

Question 3

What is the most metabolically active part of the bowel wall?

Answer 3

Mucosa, so most sensitive to hypoxia

Question 4

In non occlusive ischaemia, what does much of the tissue damage occur after?

Answer 4

Reperfusion

Question 5

What are gangrene, perforation, peritonitis, sepsis and death all complications of?

Answer 5

Ischaemia of the small bowel

Question 6

What is a result of incomplete regression of vitello-intestinal duct?

Answer 6

Meckel’s Diverticulum

Question 7

What is the rule of twos in Meckel’s Diverticulum?

Answer 7

2 inches long, 2 foot above ileocaecal valve in 2% of people

Question 8

What kind of structure are Meckel’s Diverticulum?

Answer 8

Tubular

Question 9

What might Meckel’s diverticulum contain?

Answer 9

Heterotopic gastric mucosa

Question 10

What does Meckel’s diverticulum mimick, with bleeding, perforation, or diverticulitis?

Answer 10

Appendicitis

Question 11

What three organs can give secondary tumours to the small bowel?

Answer 11

Ovary, colon, stomach

Question 12

What are three primary tumours of the small bowel?

Answer 12

1. Lymphomas
2. Carcinoid tumours
3. Carcinomas

Question 13

What are lymphomas of the small bowel like in relation to type?

Answer 13

Non Hodkins

Question 14

What are lymphomas of the small bowel derived from?

Answer 14

Maltomas (B-cell) derived

Question 15

What does enteropathy associated T cell lymphomas (associated with coeliac disease), occur in?

Answer 15

Lymphomas of small bowel

Question 16

Where is the commonest site for carcinoid tumours of small bowel?

Answer 16

Appendix

Question 17

What are small, yellow, slow growing tumours?

Answer 17

Carcinoid tumours of small bowel

Question 18

What can carcinoid tumours of small bowel cause?

Answer 18

Intussusception and obstruction

Question 19

What happens when carcinoid tumour of small bowel metastases to the liver?

Answer 19

A carcinoid syndrome occurs producing flushing and diarrhoea

Question 20

What two conditions is carcinoma of the small bowel associated with?

Answer 20

Crohn’s disease and coeliac disease

Question 21

What happens to WWC in appendicitis?

Answer 21

Increases

Question 22

What are 4 pathological features of acute appendicitis?

Answer 22

1. Acute inflammation (neutrophils)
2. Mucosal ulceration
3. Serosal congestion, exudate
4. Pus in lumen

Question 23

What type of exudate is seen in acute appendicitis?

Answer 23

Yellow surface exudate

Question 24

What is caused by an abnormal reaction to a constituent of wheat, flour, gluten which damages enterocytes and reduces absorptive capacity?

Answer 24

Coeliac disease

Question 25

What condition has a strong associated with HLA-B8 and dermatitis herpetiformis?

Answer 25

Coeliac disease

Question 26

What is the suspected component of gluten that is the toxic agent in coeliac disease?

Answer 26

Gliadin

Question 27

What is coeliac disease mediated by?

Answer 27

T lymphocytes which exist within the small intestine epithelium

Question 28

What is the normal lifespan of an enterocyte?

Answer 28

72 hours

Question 29

In coeliac disease, what is there an increasing loss of enterocytes due to?

Answer 29

IEL mediated damage

Question 30

What 4 things occur as a result of increasing loss of enterocytes due to IEL mediated damage?

Answer 30

1. Loss of villous structure 2. Loss of surface area 3. Reduction in absorption 4. Flat duodenal mucosa

Question 31

What is coeliac morphology like?

Answer 31

Flat mucosal biopsy with total villous atrophy

Question 32

In coeliac disease, where is the lesion worse?

Answer 32

Proximal bowel so duodenal biopsy is very sensitive

Question 33

What 3 antibodies can be found in serology for coeliac disease?

Answer 33

1. Anti-TTG 2. Anti-endomesial 3. Anti-gliadin

Question 34

What happens to sugars, fats, amino acids, water and electrolytes in coeliac disease?

Answer 34

Malabsorption

Question 35

What does malabsorption of fats lead to?

Answer 35

Steatorrhoea

Question 36

What can reduced intestinal hormone production lead to? (Coeliac disease)

Answer 36

Reduced pancreatic secretion and bile flow leading to gallstones