Crohn's Disease

What is Crohn's Disease?

Crohn’s disease is a type of inflammatory bowel disease.  It can cause inflammation of any part of the gastrointestinal tract from the mouth to the anus.  It also has other organs involved including the skin, eyes and joints.  It is likely caused by a combination of genetics, auto-immune and environmental factors.


Crohn’s disease is uncommon, affecting 5 in 100 000 people.  People usually have family members affected.  It can develop at any age but commonly presents at around 25 and 65 years of age.

How Does Crohn's Disease Affect The Bowel?

Crohn’s disease causes full thickness inflammation of the gastrointestinal tract wall causing ulceration and narrowing of the bowel.  This causes diarrhoea and bleeding in the faeces as well as abdominal pain and occasionally weight loss and malabsorption.  Complications may include abscesses, bowel obstruction, bowel perforation and fistulae.  


When the inflammation is active, several symptoms may occur including abdominal pain, diarrhoea, weight loss, bleeding in the stools, general feeling of unwell and fatigue.  Other organ systems can also be involved.


After taking a medical history and general examination, several investigations can be performed.  However the definitive diagnosis is made following biopsies taken during a colonoscopy and gastroscopy. Small bowel crohn's disease requires either a small bowel barium x-ray series, CT enterography or MRI for diagnosis.


Crohn’s disease is a chronic condition with no cure, however can be managed.  Medical therapy is the main course of therapy which includes steroids in the active stages and steroid sparing agents such as azathioprine or mezalazine (5-ASA) or biologics including infliximab as maintenance therapy.  Anti-diarrhoeals and anti-spasmodics, iron and nutritional supplements are occasionally required.

Failing medical therapy, occasionally surgery is required to remove affected areas of bowel particularly if there are strictures of the bowel or bowel perforations.  

What Operation Might I Have?

  • Colonoscopy/endoscopy: All patients should have regular scopes to monitor disease activity and to monitor for the development of pre-cancerous or cancerous changes.

  • Bowel resection: If a short segment of bowel is involved and not improving with medical therapy, the section of bowel may need to be removed and the bowel joined immediately or after a short period with a stoma (bag).  

  • Strictuoplasty: may be carried out to widen a narrow area of bowel. 

  • Abscess drainage

Is More Than One Operation Likely?

Yes, more than 50% of patients require an additional operation, often years later.

What About The Future?

Most people with crohn’s disease can live a productive life with minimal effect from the disease.  Pregnancy is not contraindicated but should be discussed with an obstetrician to optimise your health prior to pregnancy.  All patients should have regular scopes to monitor disease activity and to monitor for the development of pre-cancerous or cancerous changes.