Crohn's Disease

Question 1

Where does Crohns typically affect?

Answer 1

terminal ileum and colon

but may be seen anywhere from the mouth to anus.

Question 2

Does Crohns cause inflammation in all layers, or only superficial inflammation?

Answer 2

All layers down to serosa

=> patients are prone to strictures, fistulas and adhesions

Question 3

At what age does Crohns typically present?

Answer 3

late adolescence or early adulthood

Question 4

Clinical features of Crohns disease

Answer 4

• weight loss
• lethargy
• diarrhoea +/- blood
• abdo pain
• perianal disease: e.g. Skin tags or ulcers

Question 5

What initial investigations may point towards a diagnosis of crohns disease?

Answer 5

• raised inflammatory markers
• increased faecal calprotectin
• anaemia
• low vitamin B12 and vitamin D

Question 6

Describe some of the “extra-intestinal” symptoms of Crohns disease

Answer 6

Arthritis - asymmetric
Erythema nodosum
Episcleritis
Osteoporosis

Question 7

What features on colonoscopy/endoscopy may indicate Crohns disease

Answer 7

deep ulcers
skip lesions

Question 8

Histological evidence of Crohns on biopsy

Answer 8

Inflammation in all layers from mucosa to serosa
goblet cells
granulomas

Question 9

What lifestyle advice is often given to Crohns patients to manage their disease?

Answer 9

Stop Smoking

Question 10

Drugs which aim to induce remission

Answer 10

Steroids (oral/IV)
Enteral feeding
5-ASA drugs (e.g. mesalazine)
Azathioprine/mercaptopurine may be used as an add-on BUT NOT as monotherapy

infliximab in refractory disease and fistulating Crohn’s.

metronidazole - peri-anal disease

Question 11

What drugs are given to maintain remission?

Answer 11

azathioprine or mercaptopurine = first-line

Methotrexate second line

Question 12

What percentage of Crohns patients will go on to have surgery?

Answer 12

80%

Question 13

What surgical procedures are common for patients with Crohns disease?

Answer 13

stricturing terminal ileal disease = ileocaecal resection

segmental small bowel resections

stricturoplasty

complex perianal fistulae = seton suture

perianal abscess = I+D plus Abx
- a draining seton may also be placed if a tract is identified

Question 14

Name some complications of Crohns disease

Answer 14

• small bowel cancer
• colorectal cancer (higher risk with UC)
• osteoporosis

Question 15

What must you assess before starting a patient on azathioprine or mercaptopurine?

Answer 15

thiopurine methyltransferase (TPMT) activity