What are the UK guidelines for managing Crohn's disease?

UK Guidelines on Management of Crohn's Disease

The British Society of Gastroenterology (BSG) consensus guidelines recommend against using 5-ASA medications for induction or maintenance treatment of Crohn's disease, and instead recommend thiopurines or methotrexate as maintenance therapy following corticosteroid induction for moderate to severe disease. 1

Diagnosis and Assessment

Diagnostic Approaches

• Ileocolonoscopy with biopsies is the primary diagnostic tool
• Cross-sectional imaging techniques:
  • CT enterography
  • MR enterography (preferred due to lack of radiation)
  • Small bowel follow-through
• Capsule endoscopy when small bowel involvement is suspected but not confirmed by other methods
  • Use patency capsule first in patients with suspected strictures 1
• Balloon-assisted enteroscopy reserved for cases requiring tissue diagnosis when other methods are inconclusive or when therapeutic intervention is needed 1

Disease Activity Assessment

• Clinical symptoms
• Laboratory markers (CRP, ESR, albumin, vitamin B12, folate, vitamin D)
• Endoscopic findings
• Radiologic findings

Treatment Approach by Disease Severity

Mild to Moderate Ileocaecal Crohn's Disease

1. First-line treatment: Ileal-release budesonide 9 mg once daily for 8 weeks
   • As effective as prednisolone with fewer side effects
   • Once-daily dosing is as effective as three times daily
   • Should be tapered over 1-2 weeks after remission 1

Active Crohn's Colitis

1. First-line treatment: Systemic corticosteroids (e.g., prednisolone 40 mg daily tapering by 5 mg weekly) for 8 weeks 1
   • Ileal-release budesonide has benefit only in proximal colonic disease

Severe Disease

1. Hospitalization may be required
2. Intravenous corticosteroids
3. Consider early biologics (infliximab or adalimumab)

Maintenance Therapy

After First Flare or Infrequent Flares

• Consider no maintenance therapy with close monitoring

After Corticosteroid-Induced Remission

• Early introduction of maintenance therapy with:
  • Thiopurines (azathioprine or 6-mercaptopurine) 1
  • Methotrexate (at least 15 mg weekly, subcutaneous administration preferred) 1

Important Considerations for Immunomodulators

• Assess thiopurine methyltransferase (TPMT) activity before starting azathioprine/6-mercaptopurine
  • Do not use if TPMT activity is deficient
  • Consider lower dose if TPMT activity is below normal 1
• Monitor for neutropenia with thiopurines even with normal TPMT activity 1
• Document local safety monitoring policies for patients on immunosuppressants 1

Biologic Therapy

Indications for Anti-TNF Therapy

• Moderate to severe Crohn's disease not responding to conventional therapy
• Fistulizing disease
• Steroid-dependent disease

Infliximab

• Dosing: 5 mg/kg at weeks 0,2, and 6, then every 8 weeks 2
• Combination therapy with a thiopurine is more effective than infliximab monotherapy 1
  • Reduces immunogenicity
  • Reduces need for dose escalation

Adalimumab

• Induction: 160 mg on Day 1,80 mg on Day 15
• Maintenance: 40 mg every other week starting on Day 29 3
• Can be self-administered subcutaneously

What NOT to Use

• Do not use mesalazine (5-ASA) for induction or maintenance of remission in Crohn's disease 1
• Do not use budesonide or 5-ASA for severe presentations or exacerbations 1
• Do not use azathioprine, mercaptopurine or methotrexate as monotherapy to induce remission 1

Special Considerations

Pediatric Patients

• Consider enteral nutrition as an alternative to corticosteroids for inducing remission
  • Particularly important in children with growth concerns 1

Surgery

• Consider early in disease limited to distal ileum
• Indicated for stricturing or penetrating complications
• Device-assisted enteroscopy may be used for stricture dilatation in established disease 1

Patient Support and Monitoring

• Provide information on:
  • Smoking cessation
  • Diet and nutrition
  • Fertility and sexual relationships
  • Prognosis and cancer risk
  • Side effects of treatment 1
• Offer multidisciplinary support for disease management
• Regular monitoring of disease activity and treatment response
• Monitor for drug side effects according to British National Formulary guidance 1

Common Pitfalls to Avoid

1. Using 5-ASA medications despite evidence showing they are ineffective
2. Failing to assess TPMT activity before starting thiopurines
3. Not using combination therapy (infliximab plus thiopurine) when indicated
4. Inadequate monitoring for neutropenia in patients on thiopurines
5. Using budesonide for colonic disease (except proximal colon)