Irritable Bowel Syndrome

Question 1

Define

Answer 1

Functional bowel disorder defined as recurrent episodes of abdominal pain/discomfort (in the absence of detectable organic pathology) for > 6 months of the previous year, associated with two of the following:

• Altered stool passage
• Abdominal bloating
• Symptoms made worse by eating
• Passage of mucous

Question 2

Causes

Answer 2

UNKNOWN

Could be visceral sensory abnormalities, gut motility abnormalities, psychosocial factors (e.g. stress), food intolerance (e.g. lactose) and many more

Question 3

Epidemiology

Answer 3

COMMON

10-20% of adults

More common in females (2:1 ratio)

Question 4

Symptoms

Answer 4

1. >6 month hx of abdominal pain relieved by defecation

OR

associated with altered stool form or bowel frequency (>3 bowel motions daily or <3 weekly)

2. AND there are >2 of:
   
   • urgency
   • incomplete evacuation
   • abdominal bloating/distension
   • mucous PR
   • tenesmus
   • worsening of symptoms after food

Also: nausea, bladder symptoms, backache Symptoms are chronic (>6 months)

Exacerbate by stress, menstruation or gastroenteritis

RED flag symptoms (refer to exclude colonic malignancy):

↓weight, anaemia, PR bleeding, late onset >60 years

Question 5

Signs

Answer 5

• Usually NORMAL on examination
• Sometimes the abdomen may appear distended and be mildly tender on palpation in one or both iliac fossae

Question 6

Investigations

Answer 6

Diagnosis is mainly from the history but organic pathology must be excluded

• Blood: FBC (anaemia), LFT, ESR, CRP, TFT, anti-endomysial/anti-tranglutaminase antibodies (coeliac disease)
• Stool examination: microscopy and culture for infective cause
• Ultrasound: exclude gallstone disease
• Urease breath test: exclude dyspepsia due to Helicobacter pylori
• Endoscopy: if other pathologies suspected

Question 7

Management

Answer 7

Advice: dietary modification

Medical: depends on the main symptoms affecting the patient

• Antispasmodics (e.g. buscopan)
• Prokinetic agents (e.g. domperidone, metaclopramide)
• Anti-diarrhoeals (e.g. loperamide)
• Laxatives (e.g. senna, movicol, lactulose)
• Low-dose tricyclic antidepressants (may reduce visceral awareness)

Psychological therapy:

• CBT
• Relaxation and psychotherapy

Question 8

Complications

Answer 8

• Physical and psychological morbidity
• Increased incidence of colonic diverticulosis

Question 9

Prognosis

Answer 9

• Chronic relapsing and remitting course of disease
• Often exacerbated by psychosocial stresses