If you have Crohn's disease, you will have inflammation and swelling in affected areas of your bowel and ulcers may form. These are similar to mouth ulcers and cause raw areas of the lining of your bowel which can bleed. Your bowel wall can become thickened and this may cause blockages. It is a chronic illness. This means that it lasts for a long time, sometimes for the rest of the affected person's life. The term chronic refers to how long a person has the illness, not to how serious a condition is.
Attribution: BUPA