6.7 Small & Large Bowel Dysfunction

Question 1

Diarrhoea
Definition
Types
Pathophysiology
Aetiology

Answer 1

Def - intestinal disorder with abnorm frequency & liquidity of faecal evacuations
- Based on: frequency, consistency, volume

Types
- Acute (<2 weeks)
- Persistent (2-4 weeks)
- Chronic (>4 weeks)

Pathophysiology - require decrease in net water absorp of 1% to cause diarrhoea

Aetiology
- Infective (Bac, viral, fungal, parasite)
- Non-infective (IBD, cancers, drugs)
- Endocrine ( Glucagonoma)
- Factitious (Purgative, Dilutional)
- Clostridium (hospital)

Question 2

Acute Diarrhoea
Aetiology
Pathogenesis

Answer 2

• Infective (Viral, Bac)
• Clostridiodes diffiale

Pathogenesis:
- Mucosal adherence
- Mucosal invasion
- Toxic production (enetero- & cytotoxin)

Question 3

With what antimicrobial agents is C. Diffiale associated with?

Answer 3

• Fluoroquinolones
• Clindamysin
• Penicillins
• Cephalosporins

Question 4

Chronic Diarrhoea
Aetiology and their mechanisms

Answer 4

Secretory - Abnorm ion (Na, Cl) transport across SB mucosa
Osmotic - Fluid into lumen
Steatorrhoea - Fat causes osmotic diarrhoea
Exudative - leaky mucosa
** Neural** - increased motility

Question 5

List and classify the 3 categories of chronic diarrhoea

Answer 5

1. Blood
- Colitis / ileuitis
- IBD, infec, ischeamia, drugs, neoplasm

2. Fat
- Steatorrhoea
- Distrupt fat (solubilisation, digest, absorption)
- Luminal (pancreatic, bile salt, bac overgrowth) / mucosal (coelic disease)

3. Water
- Secrotory vs. Osmotic
- Fast pt for 24-72 hrs (Responsive= osmotic / Unresponsive= IBD, laxative)

Question 6

What is the difference between secretory and osmotic diarrhoea?

Answer 6

Secretory - electrolyte rich
Osmotic - non-absorb solute rich (non-electrolyte)

Question 7

How do you diagnose Functional constipation?

Answer 7

_>2 of following:
-straining
- lumpy/hard stools
- sensation of incomplete evacuation
- sensation of anorectal obstruction
- <3 defaecations / week

Question 8

What is the causes of Secondary Constipation

Answer 8

Myogenic
Anorectal
Drugs

Diet / Lifestyle
Endocrine / Metabolic
Organic
Neurological

Question 9

What drugs are associated with constipation?

Answer 9

Anticholinergics
- Antihistamine
- Antispasmodics
- Antidepressants
- Antisychotics