Irritable Bowel Syndrome (IBS)

Question 1

What is IBS?

Answer 1

• chronic, functional bowel disorder characterised by abdominal pain and altered bowel habits.

Question 2

What is the Px of IBS?

Answer 2

• dysregulation in communication between the gut and brain

Question 3

What are the RF of IBS?

Answer 3

• F
• Younger age
• Stressful life events
• Anxiety and/or depression
• Gastrointestinal infection (post-infectious IBS)
• Somatic symptoms (e.g. joint pain, migraine)
• Endometriosis
• Family history of mental illness

Question 4

What other diseases are associated with IBS?

Answer 4

• Chronic pelvic pain syndrome
• Overactive bladder
• Premenstural syndrome
• Sexual dysfunction
• Fibromyalgia
• Chronic fatigue syndrome

Question 5

What are the causes of IBS?

Answer 5

• Motility problems
• Visceral hypersensitivity
• Altered mucosal and immune function
• Gut microbiome alteration
• Food sensitivity
• Psychosocial factors

Question 6

What are the clinical features of IBS?

Answer 6

Abdominal pain

• Site: lower abdomen +/- diffuse
• Origin: chronic pain, at least 1 day per week
• Character: cramping, acute episodes of sharp pain
• Associated factors: pain is frequently related to defecation. May improve or worsen
• Exacerbating factors: food and stress may worsen symptoms

Altered bowel habits

• Diarrhoea. Mucus discharge common
• Constipation

Other

• Bloating
• Belching
• Flatulence

Question 7

What are the red flags to look out for in IBS?

*if detected, think alternative diagnosis (cancer, IBD)

Answer 7

• Onset of symptoms > 50 years
• Rectal bleeding or melaena
• Unexplained weight loss (> 10% in 3 months)
• Palpable abdominal mass
• Nocturnal diarrhoea
• Significant family history (e.g. colorectal cancer, inflammatory bowel disease or coeliac disease)
• Anaemia or raised inflammatory markers

Question 8

What criteria is used to diagnose IBS?

Answer 8

• Rome IV criteria

Question 9

Describe the Rome IV Criteria to diagnose IBS

Answer 9

• recurrent abdo pain at least once a week for 3 months
• sx begin at least 6months ago
• pain associated with 2 or more of:
  
  • change in stool form
  • change in stool requency
  • related to defecation

Question 10

What are the differential diagnosis for IBS?

Answer 10

• IBD
• Colorectal cancer
• Microscopic colitis
• Diverticular disease
• Small intestinal bacterial overgrowth
• Coeliac disease
• Chronic pancreatitis
• Neurological disorders (e.g. Parkinson’s)
• Medications

Question 11

What are the classifications of IBS?

Answer 11

• IBS with predominant constipation
• IBS with predominant diarrhoea
• IBS with mixed bowel habits
• IBS unclassified

Question 12

What is faecal calprotectin test used for?

Answer 12

• sensitive biomarkers of intestinal inflammation. To differntiate between IBD and IBS

Question 13

Describe the faecal calprotectin findings

Answer 13

• FCP < 100 mcg/g: negative
• FCP 100-250 mcg/g: grey area (consider gastroenterology opinion)
• FCP > 250 mcg/g: positive (warrants endoscopic assessment)

Question 14

What Ix would you consider for IBS?

Answer 14

• Full blood count
• C-reactive protein
• Faecal calprotectin
• Coeliac testing

Question 15

How would you mx IBS?

Answer 15

• Nutrition
  
  • Exclusion of gas-producing foods
  • Avoid lactose
  • Avoid gluten
  • Low FODMAP
• Drug therapy (for moderate to severe)
• Psychological therapies
  
  • CBT
  • Psychodynamic therapy
  • Gut-directed hypnosis
  • Mindfullness

Question 16

Describethe drug therapy for IBS

Answer 16

Constipation

• First line: Ispaghula husk (bulk-forming laxative)
• Second line: Movicol (osmotic laxative)
• Third line: Lubiprostone (Cl channel activators)

Diarrhea

• First line: loperamide
• Second line: bile acid sequestrants (e.g. cholestyramine, colesevelam)
• Other options: serotonin antagonists (e.g. ondansetron)