What is the treatment approach for inflammatory bowel disease (IBD)?

Treatment Approach for Inflammatory Bowel Disease (IBD)

The treatment of inflammatory bowel disease requires a disease-specific approach based on type (Crohn's disease or ulcerative colitis), location, severity, and pattern of disease, with aminosalicylates as first-line for mild-moderate ulcerative colitis and corticosteroids, immunomodulators, or biologics for more severe disease or Crohn's disease. 1

Disease Classification and Initial Assessment

• Ulcerative Colitis (UC): Characterized by mucosal inflammation typically starting in the rectum and progressing proximally in the colon
• Crohn's Disease (CD): Characterized by transmural inflammation that can occur anywhere in the GI tract, commonly affecting the terminal ileum and colon 2

Treatment Algorithm for Ulcerative Colitis

Mild to Moderate Distal UC (Proctitis/Left-sided)

1. First-line: Combination of topical mesalazine 1g daily plus oral mesalazine 2-4g daily 1
2. Second-line: Topical corticosteroids for patients intolerant to topical mesalazine 1
3. For inadequate response: Add oral prednisolone 40 mg daily 2

Mild to Moderate Extensive UC

1. First-line: Oral mesalazine 2-4g daily or balsalazide 6.75g daily 1
2. For inadequate response: Oral prednisolone 40 mg daily, tapered over 8 weeks 2

Severe UC

Requires hospitalization for intensive intravenous therapy when:

• Failed to respond to maximal oral treatment
• Meets Truelove and Witts' criteria for severe disease 2

Inpatient management includes:

• IV corticosteroids (hydrocortisone 400mg/day or methylprednisolone 60mg/day) 1
• Daily physical examination for abdominal tenderness
• Monitoring vital signs four times daily
• Stool chart documentation
• Regular laboratory monitoring (FBC, ESR/CRP, electrolytes, albumin)
• IV fluid and electrolyte replacement
• Subcutaneous heparin for thromboembolism prophylaxis
• Nutritional support if malnourished 2

Treatment Algorithm for Crohn's Disease

Mild Ileocolonic CD

1. First-line: High-dose mesalazine (4g daily) 2

Moderate to Severe CD

1. First-line: Oral corticosteroids (prednisolone 40mg daily) 2
2. Alternative for isolated ileo-cecal disease: Budesonide 9mg daily 2

Fistulating and Perianal CD

1. First-line: Metronidazole 400mg three times daily and/or ciprofloxacin 500mg twice daily 2
2. Second-line: Azathioprine 1.5-2.5mg/kg/day or mercaptopurine 0.75-1.5mg/kg/day 2
3. For refractory disease: Infliximab 5mg/kg at weeks 0,2, and 6 2, 3

Maintenance Therapy

For Ulcerative Colitis

• Lifelong maintenance generally recommended, especially for extensive disease 2
• First-line: Mesalazine 2-4g daily 1
• For frequent relapsers: Azathioprine 1.5-2.5mg/kg/day or mercaptopurine 0.75-1.5mg/kg/day 2

For Crohn's Disease

• Immunomodulators: Azathioprine 1.5-2.5mg/kg/day or mercaptopurine 0.75-1.5mg/kg/day for steroid-dependent disease 2, 1
• For methotrexate responders: Maintenance with methotrexate 15-25mg weekly 1
• For infliximab responders: Maintenance with infliximab 5-10mg/kg every 8 weeks 1, 3

Biologic Therapy

Infliximab has demonstrated efficacy in:

• Moderate to severe Crohn's disease with inadequate response to conventional therapies 3
• Fistulizing Crohn's disease 3

Clinical trials show:

• 81% of patients receiving 5mg/kg infliximab achieved clinical response at Week 4 vs. 16% with placebo 3
• 48% achieved clinical remission vs. 4% with placebo 3
• For fistulizing disease, 68% showed fistula response with 5mg/kg infliximab vs. 26% with placebo 3

Treatment Escalation

When initial therapy fails, prompt escalation to more potent options is necessary rather than persisting with ineffective treatments 1:

1. Step 1: Aminosalicylates (for UC) or antibiotics (for CD)
2. Step 2: Corticosteroids
3. Step 3: Immunomodulators (azathioprine, mercaptopurine, methotrexate)
4. Step 4: Biologics (anti-TNF, anti-integrin, IL-12/23 inhibitors)
5. Step 5: JAK inhibitors or S1P receptor modulators
6. Step 6: Surgical intervention

Surgery Considerations

• For UC: Complete resection of involved colon can be curative 4
• For CD: Surgery typically used for complications or refractory disease 4
• Patients with severe UC should be managed jointly by a gastroenterologist and colorectal surgeon 2
• Patients should be informed about a 25-30% chance of needing colectomy in severe UC 2

Common Pitfalls and Caveats

1. Delayed Treatment Escalation: Don't persist with ineffective treatments; escalate therapy promptly when response is inadequate 1

2. Misdiagnosis: Acute onset UC can be difficult to distinguish from infectious colitis; don't delay corticosteroid treatment while awaiting stool microbiology results 2

3. Overlooking Complications: Always consider alternative explanations for symptoms (bacterial overgrowth, bile salt malabsorption, fibrotic strictures) 2

4. Inadequate Monitoring: Regular assessment of disease activity using appropriate biomarkers and endoscopic evaluation is essential

5. Medication Non-adherence: This is common with mesalamine and can lead to treatment failure 2

6. Neglecting Supportive Care: Ensure adequate fluid intake, nutritional support, and thromboembolism prophylaxis 1