Crohn's disease and ulcerative colitis: simply explained

Crohn's disease and ulcerative colitis: simply explained

Crohn's Disease and ulcerative colitis are  two of the most common forms of Inflammatory Bowel Disease (IBD). In both conditions, ulcers form and destroy the surface of the intestine causing sore or swollen intestines.

Originally, ulcerative colitis was thought to be limited to the large intestine, or colon. Recent studies from our group shows evidence that similar sores can also show up in the small intestine, occasionally. 

With Crohn's disease, the ulcers are usually deeper and sores can appear all throughout the digestive tract, starting at the mouth. Similarly, there's a related condition, common in Japan, called Behcet's disease where the ulcers can also appear around and in the eyes and the genitals, especially the vagina. 


Those who have IBD usually  experience diarrhea and abdominal pain. These symptoms can be mild, severe, or on occasion. While these symptoms can vanish after treatment, There is still potential for them to flare back up over time. 

Sometimes, the sypmtoms of IBD can be mistaken for an Irritable Bowel Syndrome (IBS) or Spastic Colon. In IBS, there are no ulcers, but the spasms that are triggered by diet or stress can cause intense abdominal pain and diarrhea. An accurate diagnosis is so important because the treatment for IBS or IBD is very different.

Other Symptoms (not in the intestine)

Sometimes, patients with IBD will have symptoms that extend well beyond the intestine. Patients with arthritis, eye, liver, gallbladder and kidney problems can have intestinal complaints.  

As many as 25% of children with Crohn's disease and some of those with ulcerative colitis will have reduced growth. Some may catch-up, if treated promptly, but growth and puberty may be delayed. As a result, these children and teens can look younger than their age. Growth issues and intestinal symptoms can interfere with attending school and participating in activities. Coping with these conditions can also cause anxiety and / or depression.

Diet and nutrition

Diet and nutrition plays a critical role for children and adults with IBD. Research reveals new information about the role of certain diets which may be as effective as some of the medicines.