What are the treatment options for colitis?

Treatment of Colitis

Initial Diagnostic Considerations

Before initiating treatment, exclude infectious causes of diarrhea through stool testing, as this is essential to avoid inappropriate immunosuppression. 1

• Obtain stool cultures and testing for Clostridium difficile, particularly before starting corticosteroids or immunosuppressive therapy 1
• For confirmed C. difficile infection: use metronidazole 500 mg three times daily orally for 10 days (non-severe) or vancomycin 125 mg four times daily orally for 10 days (severe disease) 1
• Avoid antibiotics for Shiga toxin-producing E. coli infections as they increase complication risk 1
• Measure fecal calprotectin or lactoferrin to assess inflammation severity and determine need for urgent endoscopy 1

Treatment Based on Disease Severity and Extent

Mild to Moderate Ulcerative Colitis

For proctitis (rectal disease only), start with mesalazine 1g suppository once daily as first-line therapy. 2

For left-sided or extensive mild-to-moderate colitis, initiate oral mesalazine 2-4g daily, which should be combined with topical mesalazine for superior efficacy. 2, 1

• Topical mesalazine combined with oral therapy achieves higher remission rates than oral therapy alone 1
• For patients intolerant to topical mesalazine, use topical corticosteroids as second-line therapy 1
• Oral aminosalicylates are effective for both distal and extensive disease, though remission rates are lower than topical therapy for distal disease 3

Moderate to Severe Ulcerative Colitis

Initiate oral prednisolone combined with mesalazine as first-line treatment for moderate-to-severe colitis. 2

• Taper prednisolone gradually over 8 weeks according to severity and patient response 4
• Never use corticosteroids for long-term maintenance therapy due to significant adverse effects 2, 4
• For patients failing conventional therapy, consider biologic agents: infliximab, adalimumab, vedolizumab, ustekinumab, or tofacitinib 2

Biologic Selection Strategy

• For biologic-naive patients: infliximab 5 mg/kg at weeks 0,2, and 6, then every 8 weeks is a standard approach 5
• For patients with prior infliximab exposure, particularly with primary non-response, prefer ustekinumab or tofacitinib over vedolizumab or adalimumab 2
• When there is lack of response despite adequate drug concentration, switching out of class is reasonable 2
• Assess response by week 14; patients not responding by this time are unlikely to benefit from continued dosing and should be considered for alternative therapy 5

Acute Severe Ulcerative Colitis (ASUC)

Intravenous corticosteroids are first-line treatment: hydrocortisone 100 mg four times daily or methylprednisolone 30 mg every 12 hours, with methylprednisolone preferred due to less mineralocorticoid effect. 1

Critical Management Points

• Approximately 67% of ASUC patients respond to IV corticosteroids alone 1
• Higher corticosteroid doses offer no additional benefit and increase adverse events 1
• Limit IV corticosteroid duration to 7-10 days maximum, as prolonged courses carry no additional benefit and increase toxicity 1
• Monitor daily: stool frequency, vital signs, complete blood count, CRP, albumin, and electrolytes 1

Essential Supportive Care

• Administer IV fluid and electrolyte replacement with potassium supplementation of at least 60 mmol/day to prevent hypokalaemia and toxic dilatation 1
• Provide low-molecular-weight heparin for thromboprophylaxis immediately, as rectal bleeding is not a contraindication 2, 1
• Initiate nutritional support (parenteral or enteral according to GI function) as soon as possible 2

Rescue Therapy Decision Point

Assess clinical and biochemical response after 3-5 days of IV corticosteroids; if inadequate response, initiate rescue therapy with infliximab 5 mg/kg or ciclosporin 2 mg/kg/day. 1

• Failure to improve or deterioration within 48-72 hours from initiation of medical therapy is an indication for surgery 2
• No response to second-line therapy is an indication for surgery 2
• Approximately 20-29% of ASUC patients require colectomy during the same admission 1

Surgical Indications

Subtotal colectomy with ileostomy is the preferred surgical approach in emergency settings. 2

Absolute Indications for Emergency Surgery

• Free perforation, life-threatening hemorrhage, or generalized peritonitis 2
• Toxic megacolon complicated by perforation, massive bleeding, clinical deterioration, or signs of shock 2
• Delaying surgery in critically ill patients with toxic megacolon increases perforation risk with high mortality 2

Relative Indications

• No response to maximal oral treatment with mesalazine and/or steroids with or without topical therapy 4
• No response to intravenous steroids within 3-5 days 4
• Failure of medical rescue therapy after 4-7 days 6

Maintenance Therapy

Lifelong maintenance therapy is recommended for all patients with ulcerative colitis, particularly those with left-sided or extensive disease. 2, 4

Maintenance Strategy

• Continue with the agent successful in achieving induction, except corticosteroids 2, 4
• For patients in remission on 5-ASA, continue at a dose of at least 2g/day 4
• Azathioprine 1.5-2.5 mg/kg/day or mercaptopurine 0.75-1.5 mg/kg/day are effective second-line options 1

When Discontinuation May Be Considered

• Discontinuation may be reasonable for patients with distal disease in stable remission for at least 2 years 4
• Consider disease extent, previous severity, frequency of relapses, and patient preference before stopping therapy 4
• Educate patients about recognizing early relapse signs and ensure prompt reinitiation if symptoms recur 4

Treatment Goals

The overall treatment goal has shifted from achieving clinical response to achieving biochemical, endoscopic, and histological remission to prevent long-term disease complications. 2

Critical Pitfalls to Avoid

• Wean off steroids ideally 4 weeks before surgery and stop immunomodulators associated with anti-TNF-α agents before surgery to decrease postoperative complications 2
• Screen for latent tuberculosis before initiating infliximab; treat latent infection prior to use 5
• Monitor for invasive fungal infections (histoplasmosis, coccidioidomycosis) in at-risk patients on biologics; consider empiric antifungal therapy if severe systemic illness develops 5
• Be aware of lymphoma and hepatosplenic T-cell lymphoma risk, particularly in adolescent and young adult males receiving TNF blockers with concomitant azathioprine or 6-mercaptopurine 5