What are the treatment options for Crohn's colitis and Inflammatory Bowel Disease (IBD)?

Treatment for Crohn's Colitis and IBD

For ulcerative colitis, start with topical mesalazine combined with oral mesalamine (4g/day) as first-line therapy; for Crohn's colitis, use oral budesonide 9mg/day for mild-moderate ileocaecal disease or systemic corticosteroids (prednisolone 40mg tapering) for more severe or extensive colonic disease. 1, 2, 3

Ulcerative Colitis Treatment Algorithm

Mild to Moderate Disease (Distal/Left-Sided)

• Topical mesalazine combined with oral mesalamine (4g/day) is the optimal first-line approach, as topical formulations are more effective than oral alone for distal and left-sided disease 3, 1
• If inadequate response within 2-4 weeks, add topical corticosteroids (e.g., budesonide rectal foam) 3, 1
• High-dose mesalamine (4g/day) achieves endoscopic remission rates comparable to anti-TNF therapy in moderate UC and should be continued for maintenance 3, 4

Moderate to Severe Disease (Extensive Colitis)

• Prednisolone 40mg/day tapering by 5mg weekly combined with oral 5-ASA for induction 1
• If no response within 2 weeks, initiate advanced therapy (biologics or small molecules) rather than continuing steroids 1, 2
• For hospitalized patients with severe disease, use IV methylprednisolone 40-60mg/day (typically 40mg every 8 hours) 2
• Assess response by day 3-7; if inadequate, consider rescue therapy with infliximab or ciclosporin 3, 2

Maintenance Therapy

• Continue high-dose mesalamine (4g/day) for long-term maintenance in responders 3, 1
• Never use corticosteroids for maintenance - this is a critical error 2, 3
• For steroid-dependent patients, transition to azathioprine (1.5-2.5 mg/kg/day) or biologics 3, 1

Crohn's Disease Treatment Algorithm

Mild to Moderate Ileocaecal Disease

• Budesonide 9mg once daily for 8 weeks is as effective as prednisolone with significantly fewer side effects (51% remission rate) 1, 2
• Taper budesonide over 1-2 weeks after achieving remission 1
• High-dose mesalamine (4g/day) may be considered for mild ileocolonic disease, though evidence is limited compared to UC 3, 5

Mild to Moderate Colonic Crohn's Disease

• Prednisolone 40mg tapering by 5mg weekly is the standard approach 1, 2
• Budesonide has benefit only in proximal colonic disease, not distal inflammation 1
• Exclusive Enteral Nutrition (EEN) for 4-8 weeks can be offered to motivated patients who wish to avoid corticosteroids, though compliance is challenging in adults 1

Moderate to Severe Disease

• Oral prednisone 40-60mg/day for outpatients, with response assessment at 2-4 weeks 2, 1
• IV methylprednisolone 40-60mg/day for hospitalized patients, with response evaluation within 1 week 2
• Taper prednisone gradually over 8 weeks - rapid reduction increases relapse risk 2

Steroid-Dependent or Refractory Disease

• Anti-TNF therapy (infliximab, adalimumab) is strongly recommended for patients with moderate-severe disease who fail conventional therapy or have poor prognostic factors 2, 3, 6
• Adalimumab is FDA-approved for moderately to severely active Crohn's disease in adults and children ≥6 years 6
• Alternative options include vedolizumab (for anti-TNF failures) or ustekinumab 2
• For maintenance after steroid response: azathioprine (1.5-2.5 mg/kg/day), mercaptopurine (0.75-1.25 mg/kg/day), or parenteral methotrexate (25mg IM weekly for 16 weeks, then 15mg weekly) 2, 3, 1

Critical Management Principles

What NOT to Do

• Do not use corticosteroids for maintenance therapy - this leads to steroid dependency and complications 2, 3
• Do not use low-dose mesalamine (1-2g/day) for Crohn's disease - it is ineffective 5
• Avoid long-term opioid use - associated with poor outcomes in IBD 2
• Do not use probiotics, omega-3 fatty acids, marijuana, or naltrexone - no evidence for efficacy 2

Monitoring and Escalation

• Assess response objectively with inflammatory markers (CRP, fecal calprotectin), endoscopy, or imaging - symptoms alone are unreliable 2
• For vedolizumab: evaluate response at 10-14 weeks 2
• For ustekinumab: evaluate response at 6-10 weeks 2
• Treatment goal has shifted from symptom control to achieving biochemical, endoscopic, and histologic remission 1

Special Situations

• Severe disease requiring hospitalization: Joint management by gastroenterologist and colorectal surgeon is essential 3, 1
• Surgery: Consider when medical therapy fails or complications develop (strictures, fistulas, abscesses); resections should be conservative and limited to macroscopic disease in Crohn's 3, 1
• Pregnancy: Mesalamine is safe except formulations containing dibutyl phthalate 7
• Up to 50% of Crohn's patients require surgery within 10 years, and one-third present with complicated disease at diagnosis 2