What is the treatment for microscopic colitis?

Treatment of Microscopic Colitis

Budesonide is the first-line treatment for symptomatic microscopic colitis, with a recommended dose of 9 mg daily for 8 weeks for induction of remission, followed by maintenance therapy at 6 mg daily for those who experience symptom recurrence. 1

Treatment Algorithm

First-Line Therapy

• Budesonide 9 mg daily for 8 weeks
  • More than doubles the likelihood of achieving clinical remission compared to placebo (relative risk 2.52) 1
  • Superior to mesalamine for induction of remission 2
  • Low systemic bioavailability minimizes steroid-related side effects

Before Starting Treatment

• Identify and discontinue potential medication triggers:
  • Nonsteroidal anti-inflammatory drugs (NSAIDs)
  • Proton pump inhibitors (PPIs)
  • Selective serotonin reuptake inhibitors (SSRIs)
  • Statins 3, 4
• Assess for smoking history and counsel on smoking cessation 4
• Consider testing for associated conditions:
  • Bile acid diarrhea (present in 29-41% of cases) 2
  • Celiac disease (present in 5-7% of cases) 2

Maintenance Therapy

• For patients with symptom recurrence after induction:
  • Budesonide 6 mg daily for 6 months 2, 1
  • Can be tapered to lowest effective dose
  • Reduces risk of clinical relapse by 66% 1
  • Consider discontinuation after 6-12 months
  • Monitor for bone loss with prolonged use (implement osteoporosis prevention and screening) 2, 1

Alternative Therapies (When Budesonide Not Feasible)

1. Mesalamine 3 g daily (second-line)

   • Less effective than budesonide but superior to placebo 2, 1
   • Conditional recommendation based on moderate quality evidence 2

2. Bismuth salicylate (third-line)

   • 8-9 tablets divided 3 times daily 1
   • Consider pill burden, especially in elderly patients
   • Conditional recommendation based on low quality evidence 2

3. Prednisolone/Prednisone (fourth-line)

   • Consider when cost of budesonide is prohibitive
   • Higher risk of systemic side effects
   • Conditional recommendation based on very low quality evidence 2

4. Antidiarrheal agents (e.g., loperamide)

   • Can be used as adjunctive therapy for immediate symptom relief 3, 5
   • Particularly useful in mild cases 3

Refractory Disease Management

For patients not responding to standard therapies:

• Consider immunomodulators:
  • Azathioprine
  • 6-Mercaptopurine
  • Anti-TNF agents 2, 6
• Evidence for these agents is limited to case series 2
• Recent studies support the use of biologics in budesonide-refractory cases 7

Special Considerations

• Disease Course: Variable, with some patients experiencing intermittent symptoms and others showing chronic or progressive symptoms 3
• Monitoring: No evidence that persistent histological inflammation leads to increased risk of colorectal cancer 2, 7
• Bile Acid Sequestrants: Consider cholestyramine in patients with concurrent bile acid diarrhea 2, 5
• Immune Checkpoint Inhibitor-Induced Microscopic Colitis: May require more aggressive approach with early introduction of biologics 6

Pitfalls to Avoid

• Failing to obtain biopsies from multiple segments of the colon during diagnosis, as rectal biopsies alone may miss the disease 2
• Overlooking associated conditions like celiac disease in patients with persistent symptoms 2
• Continuing potential medication triggers in patients with refractory symptoms 2, 4
• Using maintenance therapy in all patients when up to one-third may not require it 2, 1
• Neglecting bone health monitoring in patients on long-term budesonide therapy 2, 1

The treatment approach is similar for both lymphocytic colitis and collagenous colitis subtypes, with the primary goal of therapy being symptom relief and improved quality of life 2, 3.