Crohn's Disease

Question 1

Description: Briefly describe what Crohn’s disease involves

Answer 1

Inflammation from mouth to anus but not continuous, instead has skip lesions

Question 2

Aetiology/ Risk factors: What is the main cause of Crohn’s disease?

Answer 2

Cause:

- Inappropriate and persistent activation of the mucosal immune system

Question 3

Pathology: Describe the pathology and histology of Crohn’s disease (7)

Answer 3

• Can affect any level of the GI tract from mouth to anus
• Transmural inflammation (all of the layers)
• Skip lesions
• Non-caseating granuloma
• Fibrosis
• Ulceration leads to cobblestone appearance
• Narrowing of the lumen

Question 4

Symptoms: State the symptoms of Crohn’s disease that a patient would present with:

(a) Main symptoms (3)
(b) Systemic symptoms (4)

Answer 4

(a) Main symptoms
- Diarrhoea
- Abdominal pain
- Weight loss (failure to thrive)

(b) Systemic symptoms:
- Fever
- Fatigue
- Malaise
- Anorexia

Question 5

Signs: What are the extra-intestinal manifestations of Crohn’s disease? Include the organs involved (5) and the specific symptoms for each (3/4/3/(1)/3)

What about other non-specific signs?

Answer 5

Extra – intestinal manifestations/signs:
SKIN:
- Vasculitis 
- Erythema nodosum 
- Pyoderma gangrenosum

LIVER AND BILIARY TREE:

• Gallstones
• Fatty liver
• Sclerosing cholangitis
• Pericholangitis

EYES:

• Episcleritis
• Conjunctivitis
• Uveitis
• RENAL CALCULI (only in CD, not in UC) (Kidney Stones)

JOINTS:

• Ankylosing spondylitis
• Sacroiliitis
• Monoarticular arthritis

Other non-specific signs:

• Clubbing
• Aphthous ulceration

Question 6

Investigations: What investigations are done for Crohn’s disease?

(a) Blood tests (5)
(b) Stool studies (2)
(c) Other investigations (4)

Answer 6

Blood tests:

• ESR and CRP (high)
• Platelet count (high)
• White cell count (high)
• Haemoglobin (low)
• Albumin (low)

Stool studies:

• Stool culture to rule out infection
• Faecal calprotectin (> 200 = elevated)
• Colonoscopy with biopsy of the terminal ileus
• MRI (to study the small bowel)
• Capsule endoscopy
• CT scan (if acutely unwell and want to rule out complication eg abscess)

Question 7

Treatment: How do we treat Crohn’s disease?

Answer 7

• Steroids (prednisolone 40mg/day) – to induce remission
• Immunomodulators (azathioprine/ methotrexate)
• Biologics (monoclonal antibodies)
• Surgery

Question 8

Complications: What are the complications of Crohn’s disease? (5)

Answer 8

• Fistula
• Inflammation
• Stricture
• Abscess
• Colon cancer