Irritable Bowel Syndrome

Question 1

What is irritable bowel syndrome + how is it defined

Answer 1

• Relapsing functional bowel disorder –> abdo pain/ discomfort ass. w. defecation or change in bowel habit
• IBS defined by symptoms-based Dx criteria - in absence detectable organic causes

Question 2

How common is it

Answer 2

• 1-20% of UK population

Question 3

Who does it affect

Answer 3

20-30 years

M>F ( 1.7 : 1 )

Question 4

What are the causes of IBS

Answer 4

• No structural/single explanation
• Abnormal smooth muscle activity +/- visceral hypersensitivity
• abdnormal bowel transit time (disturbed motility)
• Linked to family

Question 5

What are the different types of IBS

Answer 5

• IBS w. constipation - IBS-C - (hard stools >25% time)
• IBS w. diarrhoea - IBS-D - (loose stools >25% time)
• IBS mixed (IBS-M) - hard and soft stool most of time

Question 6

What are the symptoms

Answer 6

• Abdo pain/discomfort
• Change in bowel habit
• Bloating/distention tension or hardness
• Altered passage of stool (straining, urgency, incomplete evacuation)
• Symptoms aggravated by eating
• Lethargy, nausea, backache, bladder symp, heartburn, dysphagia
• Psychological effects

Question 7

What are the examination signs

Answer 7

• Few and non-specific
• tender, palpable colon
• PR + pelvic exam appropriate

Question 8

How do you diagnose

Answer 8

12 weeks in 12 months w.

• abdo discomfort
• Plus 2 out of –> Abnormal stool frequency, form or passage

Question 9

What are some differential diagnoses

Answer 9

• Colonic cancer
• IBD
• Bile acid malabsorption
• Coeliac disease
• gastroenteritis
• Gynae prob –> pelvic inflammatory disease

Question 10

What investigations do you perform

Answer 10

• Ask FHx IBD/colon cancer
• Bloods (inflammatory markers) FBC, ESR, CRP
• Coeliac screen
• Faecal calprotectin (for symptoms which could be IBD)

Question 11

What is the management for IBS

Answer 11

• reduce stress + more exercise
• low/high fibre diet, ++ fluid, reduce alcohol/fizzy drinks, regular meals
• Antispasmodics e.g. mebeverine (unsafe in pregnancy)
• Loperamide (anti-motility) - unsafe in preg
• Tricyclic antidepressants (prevent nerve transmission to and from gut)
• Peppermint oil
• Abx - may change bacterial composition of GI