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Overview of Crohn's disease

Crohn's disease is one of the two main forms of inflammatory bowel diseases. In Crohn's disease, the inflammation can occur anywhere from the mouth to the anus. However, the disease commonly affects the area where the small intestine (ileum) joins the colon. Men and women have an equal chance of developing Crohn's disease. Although the disease affects patients from any ethnic background, research shows that it is prevalent among the Eastern European Jewish population.

Types of Crohn's disease

There are five types of Crohn's disease including: 

  • Crohn's colitis: Only the colon is affected
  • Gastroduodenal Crohn's disease: The stomach and the first part of the small intestine or the duodenum are chronically inflamed
  • Ileitis: The ileum is affected
  • Ileocolitis: This is the most common form of Crohn's disease and it affects the ileum and the colon
  • Jejunoileitis: The upper half of the small intestine known as the jejunoileitis is affected by the disease

Symptoms of Crohn's disease

Common symptoms of Crohn's includes diarrhea that occurs for more than 6 weeks, abdominal pain and weight loss. Blood and mucus in the stool is present for up to 50% of patients with Crohn's disease.

Causes of Crohn's disease

The exact cause of Crohn's disease is not known. However, scientific research has identified three contributing factors to the development of Crohn's disease.

The three factors are:

  • Environmental: Smoking or previous history of smoking raises a person's risk of developing Crohn's disease
  • Genetics: Those who have immediate family members with Crohn's disease are more likely to develop it
  • Mucosal immune system: The immune system starts an inflammatory response against "normal" bacteria that live in your digestive tract