Inflammatory bowel disease (IBD) is an immunological disorder with two main forms: ulcerative colitis (UC) and Crohn’s disease (CD). Both are chronic conditions characterised by inflammation of the gastrointestinal tract.

Crohn’s & Colitis UK estimates that there are more than 300,000 patients with IBD in the UK. The stigma, fear and isolation caused by IBD continues to be a problem.

Incidence of IBD can occur at any age but typically presents in late adolescence/early adulthood with another small peak of incidence in the sixth decade. People diagnosed younger generally have a more aggressive form of IBD compared to those diagnosed later in life.

Although the cause of IBD is not known, a multifactorial aetiology is thought to include:

• Genetic predisposition (family history)
• Luminal microbial antigens and adjuvants
• Immune response
• Environmental factors.

The environmental factors that predispose people to IBD are largely unknown but are thought to include smoking, childhood use of antibiotics, infectious gastroenteritis and possibly the use of NSAIDs.

Key facts

• Ulcerative colitis and Crohn’s disease are the two main forms of IBD, which is a chronic, life-long condition
• Ulcerative colitis affects the large intestine only, whereas Crohn’s disease can affect any part of the GI tract
• Depending on what surgery IBD patients may have had, this may impact on their ability to absorb certain medications
• When diagnosing IBD it is important an adequate history is taken to help rule out a differential diagnosis such as irritable bowel syndrome, gastroenteritis, malignancy, haemorrhoidal bleeding, or C. difficile or some other infection
• Immunosuppressant treatment should be interrupted if a patient develops a serious infection until the infection is controlled
• With any immunosuppressant, patients and their carers should be warned to report immediately any signs or symptoms of bone marrow suppression (e.g. unexplained bruising or bleeding; infection)
• Smoking increases the severity of Crohn’s disease and leads to poorer treatment outcomes
• The psychological and social impact of a lifelong condition like IBD should never be underestimated.