7. Appendicitis and Diverticulitis

Question 1

What is the appendix?

Answer 1

Diverticulum of caecum

Can be retro-caecal, pelvic, sub-caecal or para-ileal

Question 2

What is the blood supply to the appendix?

Answer 2

Ileocolic branch of superior mesenteric artery, coming up through mesoappendix

Question 3

What are the types of appendicitis?

Answer 3

Acute (mucosal oedema)
Gangrenous (transmural inflammation and necrosis)
Perforated

Question 4

What are the causes of appendicitis?

Answer 4

Blockage of appendiceal lumen creates a higher pressure in the appendix (lymphoid hyperplasia)
Causes venous pressure to rise (causing oedema in walls), harder for arterial blood to supply appendix, ischaemia in walls, bacterial invasion follows

Question 5

What is an alternative explanation to appendicitis?

Answer 5

Viral or bacterial infections causes mucosal changes that allow bacterial invasion of appendiceal walls

Question 6

What is the classic presentation of appendicitis?

Answer 6

Poorly localised peri-umbilical pain
Reduced appetite
Nausea/vomiting
Low grade fever
After 12-24 hrs, pain is felt more intensely in right iliac fossa

Question 7

What happens if appendix is retro-caecal or pelvic in its position?

Answer 7

May not get right iliac fossa pain
Parietal peritoneum in right iliac fossa does not come into contact with inflamed appendix
Supra-pubic pain, right sided rectal or vaginal pain

Question 8

Why does the pain present the way it does in appendicitis?

Answer 8

Appendix is retroperitoneal
Visceral afferent stimulated
Pain referred to T9,10
Following enlargement, touches wall of abdomen (parietal peritoneum), giving pain in right iliac fossa

Question 9

What are the signs of appendicitis?

Answer 9

Patients appear slightly ill
Sleight fever/tachycardia
Generally lie quite still as peritoneum is inflamed
Localised right quadrant tenderness
Rebound tenderness in right iliac fossa appears to be relatively specific

Question 10

What is the diagnosis of appendicitis?

Answer 10

Blood tests - raised WBC
History and physical examination
Pregnancy test/urine dip to rule out pregnancy or UTI

Question 11

What is the treatment for appendicitis?

Answer 11

Open appendicectomy

Laparoscopic appendicectomy

Question 12

What is diverticulosis?

Answer 12

Outpouchings of mucosa and submucosa herniate through muscularis layers
Usually in sigmoid colon
Occurs where nutrient vessels penetrate bowel wall

Question 13

What is diverticulosis caused by?

Answer 13

Increased intra-luminal pressure (low fibre diet)

Question 14

What is diverticular disease?

Answer 14

When patient experiences pain but there is no inflammation/infection

Question 15

What is acute diverticulitis?

Answer 15

When diverticula become inflamed or perforate

Question 16

What is the pathophysiology of acute diverticulitis?

Answer 16

Entrance of diverticula is blocked by faeces
Inflammation eventually allows bacterial invasion of wall of diverticula
Can lead to perforation

Question 17

What is uncomplicated diverticulitis?

Answer 17

Inflammation and small abscesses confined to colonic wall

Question 18

What is complicated diverticulitis?

Answer 18

Larger abscesses
Fistula
Perforation

Question 19

What are the symptoms d acute diverticulitis?

Answer 19

Abdominal pain at site of inflammation (usually left lower quadrant)
Fever
Bloating
Constipation
Haematochezia

Question 20

What are the signs of acute diverticulitis?

Answer 20

Localised abdominal tenderness
Distension
Reduced bowel sounds
Signs of peritonitis (following perforation)

Question 21

How do you diagnose acute diverticulitis?

Answer 21

Blood tests - raised WBC
Ultrasound
CT
Colonoscopy if large haematochezia
Elective colonoscopy after symptoms have settles to determine causes of symptoms if unclear

Question 22

What is the treatment of acute diverticulitis?

Answer 22

Antibiotics, fluid resuscitation, analgesia

Surgery if perforation or large abscess need to be drained