Distal GI tract pathology - Appendicitis and Diverticulitis

Question 1

What is appendicitis?

Answer 1

Inflammation of the appendix

Question 2

What is the appendix?

Answer 2

A diverticulum off the caecum (bulge/pouch of bowel)

Question 3

Structure of appendix vs rest of colon

Answer 3

Has complete longitudinal muscle layer - in colon/large bowel there are teniae coli which are bands of longitudinal muscle making it incomplete

Question 4

Blood supply to appendix

Answer 4

Separate from caecum

Comes up through mesentery from ileocolic branch of superior mesenteric artery

Question 5

Why is location of appendix important?

Answer 5

Changes presentation of acute appendicitis

If appendix is orientated that, when inflamed, it will not touch the parietal peritoneum then no right iliac fossa pain will occur

Question 6

Locations of appendix that can occur

Answer 6

Retro-caecal (behind caecum)
Pelvic - branching towards pelvis
Subcaecal - below caecum
Pre or Post Para-ileal (so either behind or infront of ileum)

Question 7

3 broad categories of appendicitis

Answer 7

Acute - mucosal oedema
Gangrenous - transmural inflammation and necrosis
Perforated - into peritoneal cavity (can lead to peritonitis)

Question 8

Classic cause of appendicitis

Answer 8

Blockage of lumen of the appendix creates increased pressure within it
Venous pressure rises = oedema in walls
More difficult for arterial supply to oxygenate appendix
Ischaemia
Bacterial invasion

Question 9

What can cause blockage of lumen of appendix?

Answer 9

Faecolith
Lymphoid hyperplasia (lymphoid tissue lines around lumen just outside of submucosa)
Foreign body - can lodge here

Question 10

Alternative explanation for appendicitis

Answer 10

Bacterial/viral changes cause mucosal changes to appendix allowing bacterial invasion

Question 11

Classic presentation of appendicits

Answer 11

Poorly localised peri-umbilical pain
Anorexia - don’t feel like eating
Nausea/vomitting
Low grade fever
After 12-24 hrs, pain becomes more intense in right iliac fossa

Question 12

When may someone not get right iliac fossa pain?

Answer 12

If their appendix is retro-caecal or pelvic (parietal peritoneum not in contact)

Question 13

Other pain you can get in appendicitis

Answer 13

Supra-pubic
Right-sided rectal
Vaginal

Question 14

Difficult pts when diagnosing appendicitis

Answer 14

Children - history is difficult, symptoms non-specific
Pregnancy - anatomy is different to different pain etc

Question 15

Signs of appendicitis

Answer 15

Slightly ill appearance
Slight fever
Tachycardia (slightly)
Localised right quadrant tenderness
REBOUND TENDERNESS in right iliac fossa - push in and quickly release, pain felt on release rather than palpation

Question 16

Confirming diagnosis of appendicitis

Answer 16

Blood tests - will be raised WBC
History/physical exam may be enough
Esp if rebound tenderness in RIF
CT scan if non-classical presentation

Question 16

What must you do if female presents with pain similar to appendicitis?T

Answer 16

Do pregnancy test and urine dipstick to rule out ectopic pregnancy and UTI

Question 17

Treatment for appendicitis

Answer 17

Open appendicectomy or laproscopic appendicectomy

(remove appendix either open or keyhole)

Question 18

What is diverticulosis?

Answer 18

Outpouchings of mucosa and submucosa that herniate through muscularis layer
Asymptomatic and in colon (85% sigmoid)

Question 19

Where do diverticula particularly occur?

Answer 19

Along where nutrient vessels (vasa recta) penetrate bowel wall

Question 20

Cause of diverticulosis

Answer 20

Increased intra-luminal pressure (low fibre diet)

Question 21

Diverticular disease?

Answer 21

Where patient experiences pain due to diverticulosis but there is NO inflammation/infection present

Question 22

What is acute diverticulitis?

Answer 22

Diverticula become inflamed or perforate (+/- bleeding or abscess formation)

Question 23

Pathophysiology of diverticulitis

Answer 23

similar to appendicitis
Entrance to diverticula is blocked by faeces
Inflammation allows bacterial invasion of the wall of diverticula
Can cause perforation

Question 24

2 types of diverticulitits

Answer 24

Uncomplicated - inflammation and small abscesses confined to colonic wall

Complicated - large abscesses, fistula, perforation

Question 25

Symptoms of acute diverticulitis

Answer 25

Abdominal pain at site of inflammation (left lower quadrant as in sigmoid usually)
Fever (inflammation and infection)
Bloating
Constipation (inflammation can block colonic lumen)
Haematochezia - large amounts of blood loss in faeces (bright)

Question 26

Signs of acute diverticulitis

Answer 26

Localised abdominal tenderness
Distension - oedematous
Reduced bowel sounds - not moving
Signs of peritonitis (following perforation)

Question 27

Blood test function in suspected acute diverticulits

Answer 27

Raised WBC
But need to rule out ectopic pregnancy (can do this as urine)

Question 28

Other scans to investigate if cause is acute diverticulitis

Answer 28

Ultrasound scan
CT scan - see fistula etc
Colonoscopy if large haematochezia (but careful as frail inflamed bowel can easily perforate)
Elective colonoscopy - after symptoms cleared

Question 29

Treatment for acute diverticulitis

Answer 29

Abx
Fluid resuscitation
Analgesia
(if uncomplicated this may be it)

Surgery if perforation or if abscesses need to be drained (sometimes even partial colectomy where some colon is removed)