Inflammatory Bowel Disease (IBD)

What is IBD?

Inflammatory Bowel Disease (IBD) refers to a group of chronic inflammatory conditions affecting the gastrointestinal (GI) tract. The two main types are Crohn’s disease and Ulcerative colitis. In some cases, features of both are present, and the diagnosis is unclear and this is referred to as indeterminate colitis (this is more common in children).

Crohn’s Disease

Crohn’s disease can affect any part of the digestive tract, from the mouth to the anus, but most often involves the small intestine and/or colon.

Key features:

• Patchy areas of inflammation (“skip lesions”)

• Involves all layers of the bowel wall

• Can lead to complications such as:

  • Strictures (narrowing of the bowel)

  • Fistulas (abnormal tunnels between organs)

  • Abscesses (pockets of infection)

  • Perforation (rupture of the bowel wall)

Common symptoms:

• Abdominal pain and cramping

• Chronic diarrhoea (sometimes with blood)

• Fatigue, weight loss, and poor appetite

• Night sweats and low-grade fevers

• Perianal symptoms (pain, discharge, or fistulas)

Ulcerative Colitis

Ulcerative colitis only affects the large intestine (colon and rectum), with inflammation starting at the rectum and extending proximally (upwards) in the colon.

Key features:

• Inflammation limited to the innermost lining of the bowel (the mucosal layer)

• Always involves the rectum and may extend to the entire colon in a continuous fashion

Common symptoms:

• Diarrhoea (often with blood)

• Urgency, frequent bowel movements and sense of incomplete emptying

• Abdominal discomfort or cramping

• Iron deficiency, fatigue, and weight loss

• Night sweats and low-grade fevers

What Causes IBD?

The exact cause is unknown. IBD is believed to result from an abnormal immune response in genetically predisposed individuals, triggered by environmental factors. It tends to run in families and is more common in people with a first-degree relative affected. IBD can occur in anyone and is increasingly recognised in diverse populations.

How is IBD Diagnosed?

• Blood and stool tests – to assess inflammation and rule out infection

• Colonoscopy with biopsies – the key test for diagnosis and also used for monitoring. Gastroscopy – may be used if upper GI symptoms, anaemia, or iron deficiency is present

• Imaging (MRI, CT, or video capsule endoscopy) – especially helpful in Crohn’s to assess small bowel involvement

Overview of Treatment Options

Treatment is tailored to the type, location, and severity of the disease. The main goals are to control inflammation, relieve symptoms, maintain remission, and prevent complications.

1. Diet and Lifestyle

• Nutritional therapy (e.g., EEN, PEN, or Crohn’s Exclusion Diet) may help induce remission
  ➤ Nutritional Therapy for IBD – evidence-based dietary approaches

• Smoking cessation

• Nutritional supplements may be necessary

2. First-Line Medications

• 5-ASA drugs (e.g., mesalazine) for mild to moderate ulcerative colitis (oral and/or topical)

• Corticosteroids (e.g., prednisolone, budesonide) to manage moderate or severe flare-ups short-term. Corticosteroids are usually given orally but can be given topically (rectal) for ulcerative colitis affecting the distal colon

3. Escalated Medical Therapies

• Immunomodulators (e.g., azathioprine, methotrexate)

• Biologic agents (e.g., anti-TNF agents, vedolizumab, ustekinumab)

• Small molecules (e.g., JAK inhibitors like tofacitinib or upadacitinib)

4. Surgery

• Usually required for some people with severe disease or complications

Complications of IBD

Crohn’s disease may lead to:

• Abscesses, fistulas, strictures, bowel obstruction, or perforation

Ulcerative colitis may lead to:

• Acute severe colitis or fulminant colitis – both are medical emergencies that require urgent treatment

Increased risk of bowel cancer:

• Long-standing inflammation, particularly in the colon, increases colorectal cancer risk

• Regular surveillance colonoscopy is advised for all patients with:

  • Left-sided UC or Crohn’s colitis involving at least one-third of the colon

  • Starting 8 years after diagnosis

  • Frequency depends on disease control, family history, and other risk factors (usually every 1–5 years)

Nutritional deficiencies and osteoporosis

Growth delay in children and adolescents

Psychological impacts: Anxiety, depression, and reduced quality of life

Medication-related side effects