Chronic diarrhoea

Question 1

Types of chronic diarrhoea (depending on causes)?

Answer 1

• osmotic
• secretory
• inflammatory
• altered motility

Question 2

What causes osmotic diarrhoea?

Answer 2

Large volume of non-absorbable solutes in the gut lumen

-e.g. lactulose therapy

Question 3

What causes secretory diarrhoea?

Answer 3

Increased secretion into gut lumen and reduced absorption due to:

• drugs (antibiotics)
• bacterial enterotoxins (Campylobacter, C diff)
• excess hormone secretion (insulinoma)

Question 4

What causes inflammatory diarrhoea?

Answer 4

IBD
Crohn’s
ulcers
colonic infections

Question 5

What causes altered motility?

Answer 5

diabetes
drugs (erythromycin)
IBS

Question 6

What symptoms are suggestive of organic disease?

Answer 6

Diarrhoea for < 3 months
Nocturnal diarrhoea
Significant weight loss
Mucous and blood in stool
Abdominal pain

Question 7

Red flags of colorectal cancer?

Answer 7

• Age >60
• persistent rectal bleeding without pain
• persistent change in bowel habit
• weight loss
• iron-deficiency anaemia
• familial history

Question 8

Investigations for patients with chronic diarrhoea?

Answer 8

• stool microscopy and culture
• full blood count
• Urea and Electrolytes
• CRP
• LFTs
• Thyroid function
• IgA for coeliac disease

Question 9

How is IBS diagnosed?

Answer 9

-abdominal discomfort or pain for 3 days a month in the past 3 months

2 or more of:

• pain relived by defecation
• pain is associated with change in stool frequency
• pain onset associated with change in stool form

Question 10

Dietary advice for IBS patients?

Answer 10

• eat regularly, small gaps between meals
• 8 cups of fluid per day
• low fibre
• low fruit (3 portions)
• no sweeteners
• try probiotics
• try excluding specific foods
• oats and linseed for bloating