Pathology of the small intestine

Question 1

What are the 2 classes of conditions that can lead to ischaemia of the small bowel?

Answer 1

Mesenteric arterial occlusion
Non-occlusive perfusion insufficiency

Question 2

What are some conditions that can lead to mesenteric artery occlusion?

Answer 2

Mesenteric artery atherosclerosis
Thromboembolism from the heart

Question 3

What are some conditions that can lead to non-occlusive perfusion insufficiency?

Answer 3

Shock
Strangulation obstructing venous return
Drugs (e.g. cocaine)
Hyperviscosity

Question 4

What is the progression of mesenteric ischaemia?

Answer 4

Mucosal infarction
Mural infarction
Transmural infarction
Necrosis
gangrene
Bowel perforation

Question 5

What are some symptoms of acute mesenteric ischaemia?

Answer 5

Nausea
Vomiting
Abdominal pain

Question 6

Who is most at risk of chronic mesenteric ischaemia?

Answer 6

Females
Aged 50-70
History of atherosclerosis
Smoking
Atrial fibrillation

Question 7

What are some symptoms of chronic mesenteric ischaemia?

Answer 7

Moderate-to-severe colicky, poorly localised pain (Angina of the bowel)
Weight loss
Postprandial pain
Fear of eating
Nausea
Vomiting
Bowel irregularity

Question 8

What are some investigations that can be performed in mesenteric ischaemia?

Answer 8

CT angiography - Gold standard
Bloods => Lactate raised, CRP normal

Question 9

What are some possible complications of untreated mesenteric ischaemia?

Answer 9

Fibrosis
Stricture
Mesenteric angina
Obstruction
Gangrene
Perforation

Question 10

What are some treatment options in mesenteric ischaemia?

Answer 10

Bowel resection
SMA embolectomy

Question 11

Where do most secondary tumours of the small intestine metastasise from?

Answer 11

Ovaries
Stomach
Colon

Question 12

What are the 3 main primary tumour types of the small intestine?

Answer 12

Non-hodgkin lymphomas
Neuroendocrine tumours
Carcinomas

Question 13

What are the 2 main types of lymphoma that can affect the small intestine?

Answer 13

Maltomas (B-cells)
Enteropathy associated T cell lymphomas (Associated with Coeliac disease)

Question 14

What are some paraneoplastic syndromes associated with neuroendocrine tumours of the small intestine?

Answer 14

Flushing
Diarrhoea

Question 15

What is appendicitis?

Answer 15

Inflammation of the appendix, usually caused by obstruction of the appendiceal lumen

Question 16

Who is acute appendicitis most common in?

Answer 16

It is the most common cause of acute abdomen in children and young adults, affecting most people in their 2nd and 3rd decade

Question 17

What are some common causes of appendicitis?

Answer 17

Idiopathic
Faecolith blockage (Dehydration)
Lymphoid hyperplasia
Parasites
Tumours

Question 18

What is a faecolith?

Answer 18

A small, dehydrated ball of faecal matter, caused by a decrease in fluid intake

Question 19

How can blockage of the appendiceal lumen lead to appendicitis?

Answer 19

Blockage causes entrapment of bacteria, which grow , causing damage to the mucosa, leading to neutrophilic activation and pus build up, which can cause ischaemia of surrounding veins, resulting in necrosis and perforation

Question 20

What are some possible complications of untreated appendicitis?

Answer 20

Rupture
Peritonitis
Abscesses
Fistula
Sepsis
Liver abscesses

Question 21

Describe the pain felt in acute appendicitis?

Answer 21

Starts poorly localised to the umbilical region as visceral afferent nerves enter the spinal cord at T8 - T12

As the appendix becomes inflamed, it begins to rub against the soma, therefore causing stimulation of somatic sensory nerves, which localise the pain the the right iliac fossa

Question 22

What is McBurney’s point?

Answer 22

The theoretical point of maximum tenderness in appendicitis

It is found 1/3rd of the way between the superior anterior iliac spine and the umbilicus

Question 23

What is the usual presentation of a patient with appendicitis?

Answer 23

Umbilical pain that has moved down to RIF
Worse on coughing or laughing
Colicky pain
Hasn’t opened bowels that day

Question 24

What are some possible clinical signs in appendicitis?

Answer 24

Mild pyrexia
Mild tachycardia
Guarding
Rebound
Rovsing’s sign
Psoas sign
Obturator sign

Question 25

What is Rovsing’s sign?

Answer 25

This is a sensation in which pressing on a patients left iliac fossa will cause pain in the right iliac fossa, associated with acute appendicitis

Question 26

What is the Psoas sign?

Answer 26

This is a clinical sign in which the patient keeps their right leg flexed, as this alleviates pain due to the appendix being lifted off the psoas muscle

Question 27

What is the obturator sign?

Answer 27

If the appendix is touching the obturator internus, then rotating around the hip will cause pain

Question 28

What are some investigations in appendicitis?

Answer 28

FBC
CRP
U&E
Urinalysis for pregnancy
Ultrasound
Then CT

Question 29

How is appendicitis usually treated?

Answer 29

Analgesics
Anti-pyretics
Appendectomy, usually laparoscopic

Question 30

What is the most common site of neuroendocrine tumours in the GI tract?

Answer 30

Appendix

Question 31

What is a neuroendocrine tumour of the GI tract?

Answer 31

These are small, yellow, slow growing tumours that can secrete hormone like substances

Question 32

What are some risks of neuroendocrine tumours?

Answer 32

Bowel obstruction
Intususception
Carcinoid syndrome if liver metastases