Crohn’s disease is similar to Ulcerative Colitis but can affect any part of the gastrointestinal tract. Diarrhoea, abdominal pain and feeling generally unwell are frequent symptoms. It tends to occur in young adults and is more likely in smokers. Treatment usually requires medication to modulate the immune system. The pattern of inflammation needs to be determined by colonoscopy and often with magnetic resonance (MRI scans) of the abdomen.