Inflammatory Bowel Disease

Question 1

Define inflammatory bowel diseases

Answer 1

They are idiopathic immune mediated chronic disorders.

They are associated with other autoimmune disorders. The cause is unknown but thought to be multifactorial.

Question 2

What is the peak incidence?

Answer 2

15-40 years

Question 3

How does smoking effect IBD?

Answer 3

Smoking increases the risk of Crohn’s disease but decreases the risk of UC

Question 4

Which antibodies are associated with Crohn’s?

Answer 4

ASCA

Question 5

Which antibodies are associated with UC?

Answer 5

pANCA

Question 6

Give the main differences between Crohn’s and UC

Answer 6

Crohn’s

• Small and large bowel
• Skip lesions
• Thickened bowel wall with cobblestoning
• Strictures and deep fissues, fistulae
• Granulomas
• Inflammation through mucosa to muscle

UC

• Only large bowel (always rectum)
• Continuous
• Thin bowel wall with loss of vascularisation
• No strictures, fissures, fistulae or granulomas
• Inflammation is symmetrical and confined to mucosa

Question 7

What parts of the bowel are most typically affected by Crohn’s?

Answer 7

The proximal colon and terminal ileum

but Crohn’s can affect any part of the GI tract

Question 8

Describe the inflammation in Crohn’s

Answer 8

Transmural
Granulomatous
Skip lesions

Question 9

How do patients with cron’s typically present?

Answer 9

Chronic diarrhoea (more than 6 weeks)
may be bloody or assoc with mucus and abdo pain

Systemic Sxs e.g. weight loss, fatigue, anorexia, fever

In children - poor growth and delayed puberty

Question 10

Give some extra-intestinal manifestations of Crohn’s

Answer 10

• Apthous ulcers of mouth
• Anaemia signs
• Anal and peri-anal lesions e.g. skin tags, abscesses, fistulae
• Clubbing, erythema nodosum, pyoderma gangrenosum
• Conjunctivitis, episcleritis, uveitis
• Enteropathic arthritis (can present as ank spond)
• Perineal scarring

Question 11

What investigations should be performed?

Answer 11

Bloods:
FBC, CRP, U&Es, LFTs

Stool:
culture (oc&p, C.diff toxin)

Imaging:
Endoscopy (ileocolonoscopy) and biposy (to confirm Dx)

Question 12

What indicates active disease?

Answer 12

Raised CRP

Question 13

What is seen on a biopsy?

Answer 13

Mucosa may be bleeding and friable and have a cobblestone appearance with ulceration and skip lesions

Question 14

What investigations should be carried out after diagnosis of Crohn’s has been confirmed? (and why)

Answer 14

• Barium studies or small bowel follow through
• CT and MRI enterography

To examine location and extent of the disease
and to look for strictures, fistulae and abscesses

Question 15

How do you manage a flare of Crohn’s?

Answer 15

A to E

• IV fluids
• Monitor stools with a bristol stool chart
• Bloods: inflammatory markers and electrolytes
• AXR to rule out toxic megacolon
• Give LMWH due to risk of VTE

Inducing remission:

• IV or oral Steroids
• Azathioprine or Mercaptopurine (with steroids if more than 2 flares within 12 months)
• Infliximab or adalimumab (if no response to above therapy)
• Surgery (if no response to anti-TNF)

Question 16

What must be checked before starting someone on Azathioprine or mercaptopurine?

Answer 16

TPMT activity (if its low this is a contraindication)

Question 17

How is stable Crohn’s disease managed?

Answer 17

• Smoking cessation
• Azathioprine or 6-mercaptopurine monotherapy
• Methotrexate (and folate)