Crohn's disease

Crohn’s Disease

Crohn’s disease is a form of IBD wherein inflammation can affect any part of the digestive tract, from the mouth to the anus. The inflammation in Crohn’s disease is transmural, meaning it can occur throughout the entire width of the intestinal wall.

Symptoms include:

  • Abdominal pain
  • Diarrhoea
  • Fatigue
  • Weight loss
  • Malnutrition
  • Fever
  • Rectal bleeding


The disease is broken down further into five types, depending on the location of the affected areas:

  • Ileocolitis: is the most common form of Crohn’s disease. It affects the ileum (section of small bowel just before the colon) and the colon (i.e., large intestine).
  • Ileitis: disease activity islimited to the ileum.
  • Gastroduodenal: disease activity affects the stomach and duodenum (i.e., first section of the small intestine).
  • Jejunoileitis: disease activity affects the jejunum (i.e., middle section of the small bowel, in between the duodenum and ileum).
  • Crohn’s (granulomatous) colitis: disease activity affecting the colon only.


Crohn’s disease canalso cause:

  • Fistulas: abnormal connections that form a channel between the intestine and a area (e.g., different section of bowel, skin) potentially allowing fluids or matter to pass through.
  • Strictures: scarring of the intestinal wall causes a narrowing of the bowel, which can result in a bowel obstruction (i.e., passage of food being blocked).
  • Anal fissure: tear or split in the tissue around the anus.
  • Ulcers:open sores may form in any part of the digestive tract.
View pictures of normal gut and Crohn's disease (Warning: medical images