Crohn’s Disease

What is Crohn’s disease?

Crohn’s disease belongs to a group of autoimmune conditions known as inflammatory bowel diseases (IBD). Crohn's disease is a chronic (recurrent or flaring-up) inflammation of the digestive tract, which usually affects the intestines, specifically the small bowel (ileum) and the colon, but it can affect anywhere along the digestive tract from the mouth to the anus. The main symptoms are chronic diarrhea, fever and weight loss. The specific causes of the condition are unknown.


Crohn's disease is an autoimmune disease. This means that the body's immune system mistakenly harms healthy body tissue. This process of inflammation causes the bowel to swell and bleed, affecting the ability of the bowel to take up nutrients. The condition is more common in people between the ages of 15 and 35 years. Diet and stress don't cause the disease but they may aggravate it. Risk factors include smoking and having a blood relative with Crohn's disease. Other specific causes are not known.


Symptoms may include persistent diarrhea, abdominal cramps and constipation. Other symptoms include fatigue and weight loss. Fistulas (open passageways between the intestine and nearby structures, such as the bladder or vagina) may develop. Having chronic diarrhea can cause problems with sufficient nutrient uptake, affecting growth and development in adolescents.


The standard test to diagnose Crohn's disease is a endoscopy (a camera through the mouth or anus to look at the bowel). A sample (biopsy) of the bowel will be taken and tested to confirm the diagnosis. Some blood tests may be necessary to monitor inflammation and check for complications, such as vitamin deficiency or a reduced number of red blood cells). A stool sample may be needed to exclude other causes of persistent diarrhea and belly pain.


Taking anti-inflammatory medications to suppress the inflammatory reaction in the bowel is the most common treatment. This treatment can help suppress the severe episodes or extend illness-free intervals, but does not cure the condition. Reducing the intake of dairy products, fatty foods and fiber may also help to reduce the symptoms. Consulting a dietitian may be helpful.

Other names for Crohn’s disease

  • Crohn’s syndrome
  • Regional enteritis