Can prednisone reduce the Endoscopic Mayo subscore in patients with inflammatory bowel disease, such as ulcerative colitis, who are partially refractory to prednisone?

Prednisone Does Not Reduce Endoscopic Mayo Subscore in Patients Partially Refractory to Prednisone

In patients with ulcerative colitis who are partially refractory to prednisone, continuing or escalating corticosteroid therapy will not meaningfully reduce the Endoscopic Mayo subscore and should be abandoned in favor of treatment escalation to thiopurines, anti-TNF therapy, vedolizumab, or tofacitinib. 1

Understanding Steroid Refractoriness and Endoscopic Response

The fundamental issue is that partial refractoriness to prednisone indicates the disease has moved beyond the therapeutic window where corticosteroids can achieve mucosal healing. The evidence demonstrates:

• Prolonging treatment with high-dose oral corticosteroids has a diminishing chance of achieving remission, and patients who do respond often become corticosteroid-dependent rather than achieving durable endoscopic improvement. 1, 2

• The British Society of Gastroenterology explicitly states that moderate disease refractory to oral steroids should be treated either with intravenous steroids or anti-TNF therapy (preferably combined with thiopurines), not with continued oral prednisone. 1

• Approximately 50% of patients who initially respond to corticosteroids will relapse when steroids are withdrawn, indicating that steroids do not produce sustained endoscopic healing in many patients. 1

Why Endoscopic Mayo Subscore Won't Improve

The Endoscopic Mayo subscore specifically measures mucosal inflammation severity (0-3 scale: normal, mild disease with erythema/decreased vascularity, moderate disease with marked erythema/erosions, or severe disease with spontaneous bleeding/ulcerations). 1

Key evidence against continued prednisone in partial responders:

• Clinical improvement does not equal endoscopic improvement. Patients may experience symptomatic relief while maintaining significant mucosal inflammation (Mayo endoscopic subscore >1). 1

• In the ACT trials of infliximab, only 21.5% of steroid-treated patients achieved steroid-free remission by week 30, demonstrating that most patients on steroids fail to achieve complete disease control including endoscopic healing. 1

• A 2025 randomized controlled trial showed that even adding pulse methylprednisolone (500mg x 3 days) to oral prednisone 60mg daily did not improve medium or long-term clinical-endoscopic remission rates in moderately active UC (28% overall remission at weeks 8 and 54, with no significant difference between groups). 3

The Critical Treatment Decision Point

Patients requiring two or more corticosteroid courses within a calendar year require treatment escalation with thiopurines, anti-TNF therapy, vedolizumab, or tofacitinib—not more prednisone. 1, 2

The definition of steroid refractoriness includes:

• Patients who flare when steroids are withdrawn (steroid-dependent)
• Patients with persistent active disease despite adequate steroid dosing (40mg prednisolone daily for 2 weeks)
• Patients with systemic symptoms (fever, severe pain, significant anemia) who should be admitted for inpatient management 1, 2

Evidence-Based Treatment Algorithm for Partial Steroid Responders

If a patient shows partial response to prednisone 40mg daily after 2 weeks:

1. Do not continue or escalate oral prednisone beyond the standard 6-8 week taper 1, 2

2. Initiate treatment escalation immediately with:

   • Anti-TNF therapy (infliximab or adalimumab), preferably combined with thiopurines for infliximab 1
   • Vedolizumab as an alternative integrin antagonist 1
   • Tofacitinib (JAK inhibitor) for patients who have failed other therapies 1
   • Thiopurines alone only if the patient is not severely ill and can tolerate the 3-4 month onset of action 1

3. For patients with moderate disease and systemic symptoms, consider intravenous corticosteroids as a bridge to biologic therapy or as assessment for need for hospitalization, but this is a short-term rescue strategy, not a means to improve endoscopic scores. 1

Common Pitfalls to Avoid

Critical mistake: Continuing oral prednisone beyond 8 weeks hoping for endoscopic improvement. This exposes patients to cumulative steroid toxicity (approximately 50% experience short-term adverse effects including acne, edema, sleep/mood disturbance, glucose intolerance, dyspepsia) without achieving mucosal healing. 1

Approximately 22% of patients become corticosteroid-dependent at 1 year, and corticosteroids have no role in maintenance therapy for UC. 2

Patients with systemic symptoms or those generally unwell should be admitted for inpatient management rather than continuing outpatient oral steroids, as there is increasing risk of infective, metabolic, and surgical complications for deteriorating patients who may require emergency colectomy. 2

The Endoscopic Healing Target

Endoscopic remission is defined as Mayo endoscopic subscore ≤1, with complete endoscopic remission restricted to score 0 (normal or completely healed mucosa). 1

Mucosal healing predicts long-term outcomes including reduced colectomy rates, but prednisone in partially refractory patients will not achieve this target. The evidence from biologic trials demonstrates that anti-TNF therapy achieves endoscopic healing rates of 27.6% for budesonide MMX (a topically-acting corticosteroid), suggesting that systemic corticosteroids alone are insufficient for mucosal healing in refractory disease. 1

The validated UCEIS (Ulcerative Colitis Endoscopic Index of Severity) and Mayo endoscopic subscore should be used to objectively document lack of endoscopic response and justify treatment escalation. 1