Crohns.jpg
Granuloma formation in a colon biopsy

Definition
[1]
Crohn's Disease (or CD) is a chronic inflammatory disease that can affect any part of the gut from the mouth to the anus.

Incidence

[2]
50-100 per 100 000 lifetime risk

Age

15-40 and 60-80 (bimodal distribution)

Gender

More common in females than males

Risk Factors

[3]
  • Family History of Crohn's Disease
  • Caucasian
  • Smoking

Signs and Symptoms

[4]

Pathophysiology

[5]
The pathophysiology of Crohn's Disease is complicated and not entirely understood. It is thought to be initiated by inflammatory infiltration of the gut leading to superficial mucosa ulceration. The inflammation continues to extends into deeper layers and causes granuloma formation - a sign of chronic inflammation. Crohn's Disease may also have extra-intestinal signs including eye, skin and joints.

Investigations

[6]

Bloods

Imaging

  • Endoscopy -skip lesions, ulceration, oedema, cobblestoning
  • Abdominal X-ray - bowel dilation, calcification, abscesses
  • CT scan - skip lesions, mucosal thickening, inflammation, abscesses, fistulae
  • MRI - skip lesions, mucosal thickening, inflammation, abscesses, fistulae

Other

  • Stool Sample - Absence of infectious agent
  • Bowel Biopsy - Granulomas, transmural inflammation, submucosal fibrosis, neutrophil infiltration

Diagnosis

[7]
There is no test that completely confirms the diagnosis of Crohn's Disease but imaging should be highly suggestive. Diagnosis requires clinical reasoning and ruling out other possibilities

Differentials to rule out

Treatment

[8]

Non-Pharmacological

  • Nil by mouth, IV fluids (if severe attack)
  • Stop smoking

Pharmacological

Surgical

  • Surgical repair of fistulae
  • Surgical drainage of abscesses

Management

[9]
Patients with Crohn's Disease should be followed up by a Gastroenterologist and also monitored for side effects of glucocorticoid use. Patients should also be notified of local support groups and the need to seek medical advice if symptoms return.

Complications

[10]

Prognosis

[11]
Crohn's Disease does not significantly reduce life expectancy but can affect quality of life, although this can be managed both medically and surgically. Patients who develop Crohn's Disease at a younger age are more likely to have more significant disease.

See Also

Oxford Handbook of Clinical Medicine - 9th Edition p274
BMJ Best Practice - Crohn's Disease

Citation

Colon biopsy image: "Crohn's disease - colon - high mag" by Nephron - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Crohn%27s_disease_-_colon_-_high_mag.jpg#/media/File:Crohn%27s_disease_-_colon_-_high_mag.jpg
  1. ^ Oxford Handbook of Clinical Medicine - 9th Edition p274
  2. ^ Oxford Handbook of Clinical Medicine - 9th Edition p274
  3. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  4. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  5. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  6. ^ Oxford Handbook of Clinical Medicine - 9th Edition p274
  7. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  8. ^ Oxford Handbook of Clinical Medicine - 9th Edition p274
  9. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  10. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html
  11. ^ http://bestpractice.bmj.com.ezp.lib.unimelb.edu.au/best-practice/monograph/42.html