IBD

Question 1

What are the contributing factors of IBD?

Answer 1

• environmental factors (eg. Antibiotics, intestinal inf.)
• genetic predisposition
• gut microbiota
• host immune response

Question 2

Describe the presentation of infective colitis

Answer 2

• short history of diarrhoea +/- vomiting
• abrupt onset +/- resolution of symptoms
• systemic upset
• fever
• travel + unwell contacts
• immunocompromised

Question 3

What is the investigation and management of infective colitis?

Answer 3

Investigation:
- stool culture (x4)
- CDT

Management:
- conservative if immunocompetent (even if bacterial gastroenteritis confirmed)

Question 4

Describe the presentation of ischaemic colitis

Answer 4

• increased risk in elderly, CV disease, HF
• abrupt onset pain + bloody diarrhoea
• +/- systemic inflammatory response syndrome (SIRS)

Question 5

Describe the investigation findings and treatment of ischaemic colitis

Answer 5

• CT may show segmental colitis in watershed areas (areas receiving dual supply from distal branches of their arteries)
• splenic flexure + rectosigmoid junction
• treatment is usually conservative
• IV fluids +/- antibiotics (if unstable)

Question 6

When should you decide to admit a patient with suspected UC?

Answer 6

If they are producing >6 stools a day + signs of systemic upset

Question 7

What imaging is useful in colitis?

Answer 7

• abdominal X-ray
• assess disease extent + severity

Question 8

Define megacolon + toxic megacolon

Answer 8

• megacolon: transverse diameter of colon >5.5cm or caecum >9cm
• toxic megacolon: megacolon + signs of systemic toxicity (EMERGENCY - risk of perforation)

Question 9

What is an X-ray sign of bowel inflammation?

Answer 9

Thumb-printing

Question 10

What are the 4 layers of the bowel?

Answer 10

• mucosa
• sub-mucosa
• muscularis
• sub-serosa

Question 11

Describe the pathology of CIBD

Answer 11

Acute changes:
- acute inflammation
- ulceration
- loss of goblet cells
- crypt abscess formation (neutrophil aggregation)

Chronic changes:
- architectural changes
- paneth cell metaplasia (increased plasma cells and lymphocytes)
- chronic inflammatory infiltrates in lamina propria
- neuronal hyperplasia
- fibrosis

Question 12

Describe the prescribed treatment of UC

Answer 12

• mesalazine
• 4.8g (in flare ups)
• 2.4g daily maintenance (decreases metaplasia and polyp formation)

Question 13

At what point would you consider a treatment escalation from mesalazine in UC?

Answer 13

• severe relapse/frequent relapses of disease which require 2 or more corticosteroid courses within 12 month period
• azathioprine/mercaptopurine (immunosuppressants)
• biologics (anti-IL/TNF)/surgery

Question 14

When treating a patient in hospital for UC when can you decide that steroid treatment is not working efficiently?

Answer 14

If on day 3 of treatment:
- stool frequency >8
- or CRP >45
* colectomy needed (consider surgery or medical treatment with infliximab/cyclosporin)

Question 15

List the complications of UC

Answer 15

Local: haemorrhage, toxic dilation of colon

Systemic: skin (erythema nodosum, pyoderma gangrenosum), liver (sclerosing cholangitis), eyes (iritis, uveitis), ankylosing spondylitis, malignancy (esp. colorectal cancer)

Question 16

When is endoscopic surveillance for colorectal cancer commenced in UC patients?

Answer 16

After 10 years of disease (where the risk of colorectal cancer increases)

Question 17

What factors in a history/investigations does a Crohn’s disease diagnosis become more likely?

Answer 17

• family history
• evidence of malabsorption
• weight loss

Question 18

What is Crohn’s disease?

Answer 18

• chronic inflammatory condition affecting anywhere from mouth to anus
• 2x more common in smoking
• peak incidence 15-25y

Question 19

What are the symptoms of Crohn’s disease?

Answer 19

• abdo pain (central)
• diarrhoea (watery)
• weight loss
• fistulae (communication between internal adjacent structures), abscesses, oropharyngeal/gastroduodenal involvement
• eye symptoms (episcleritis, uveitis)
• joints (sacroilitis, inflammatory athropathy)
• skin (erythema nodosum)

Question 20

Contrast Crohn’s disease vs UC

Answer 20

• Crohn’s can affect the small and large bowel, UC just affects large bowel
• Crohn’s is patchy inflammation giving macroscopic ‘skip lesions’, UC is confluent and diffuse inflammation
• Crohn’s is a transmural, deeply ulcerating inflammation, UC inflammation is confined to the mucosa
• Crohn’s has granulomas presence, UC does not

Question 21

What is the medical treatment of Crohn’s?

Answer 21

• azathioprine or 6-mercaptopurine
• methotrexate (not routinely used due to side effects + teratogenicity)
• infliximab/adalimumab (anti-TNF biologics)
• vedolizumab/ustekinumab anti-cytokine)

Question 22

What are the risk factors for severity/need for surgery in Crohn’s patients?

Answer 22

• young onset
• smoking
• perianal disease
• stricturing small bowel disease