What is the recommended treatment for an acute Crohn's flare?

Treatment of Acute Crohn's Disease Flare

For an acute Crohn's disease flare, systemic corticosteroids are the recommended first-line treatment for moderate to severe disease, while budesonide 9 mg/day is preferred for mild to moderate disease limited to the ileum and/or ascending colon due to its better safety profile. 1, 2

Treatment Based on Disease Location and Severity

Mild to Moderate Disease Limited to Ileum/Ascending Colon

• Budesonide 9 mg/day is the first choice due to its high topical anti-inflammatory activity and low systemic bioavailability, resulting in fewer side effects 2, 1
• Budesonide has been shown to be superior to placebo for inducing clinical response (RR: 1.46; 95% CI: 1.03–2.07) and clinical remission (RR: 1.93; 95% CI: 1.37–2.73) 2
• Evaluate response to budesonide within 2-4 weeks 1

Moderate to Severe or More Extensive Disease

• Systemic corticosteroids (prednisolone 40-60 mg daily or equivalent) are recommended 2, 1
• Treatment should be given for a defined period of 7-10 days, as extending therapy beyond this carries no additional benefit 2
• Oral prednisolone starting at 40 mg daily has been shown to induce remission in 77% of patients with moderate disease within 2 weeks 2
• Evaluate response to systemic corticosteroids within 2-4 weeks 1

Second-Line and Maintenance Therapy

For Non-Response to Corticosteroids

• TNF inhibitors (infliximab, adalimumab, certolizumab pegol) are recommended for patients with moderate-to-severe Crohn's disease who have not responded to conventional therapy 2, 3
• Infliximab is administered at 5 mg/kg at weeks 0,2, and 6 for induction, followed by maintenance every 8 weeks 4
• Adalimumab is given subcutaneously with an induction dose of 160 mg, then 80 mg two weeks later, followed by 40 mg every two weeks for maintenance 4
• Combination therapy with a thiopurine when starting infliximab is recommended to improve efficacy and reduce immunogenicity 2, 3

Maintenance After Successful Corticosteroid Treatment

• Corticosteroids are NOT recommended for maintenance therapy due to significant side effects, including bone loss, metabolic complications, and increased risk of infections 5, 1
• Thiopurines (azathioprine 2-2.5 mg/kg/day or 6-mercaptopurine 1-1.5 mg/kg/day) should be considered for patients who require two or more corticosteroid courses within a calendar year or relapse as the dose is reduced below 15 mg 2, 1
• Methotrexate (subcutaneous or intramuscular at ≥15 mg weekly) is an alternative maintenance option 1, 3

Important Considerations and Cautions

• Nearly 50% of patients who initially respond to corticosteroids will develop dependency or relapse within 1 year 5
• Corticosteroids are ineffective for maintaining remission or healing mucosal lesions and should only be used short-term 5
• Mesalazine (5-ASA) is not recommended for induction or maintenance of remission in Crohn's disease 1, 6
• Antibiotics have not consistently demonstrated efficacy for luminal Crohn's disease and are not recommended as primary therapy 2, 1
• Monitor for corticosteroid side effects including bone loss, glucose intolerance, increased intraocular pressure, and increased infection risk 5
• For patients with severe disease not responding to initial therapy, early surgical consultation may be warranted 2

Treatment Algorithm

1. Assess disease location and severity:

   • Mild-moderate limited to ileum/ascending colon: Budesonide 9 mg/day 2, 1
   • Moderate-severe or extensive disease: Systemic corticosteroids (prednisolone 40-60 mg/day) 2, 1

2. Evaluate response within 2-4 weeks 1

3. If responding to initial therapy:

   • Begin tapering corticosteroids
   • Consider maintenance therapy with thiopurines or methotrexate 2, 1

4. If not responding to initial therapy:

   • For corticosteroid resistance: Initiate anti-TNF therapy (infliximab or adalimumab), preferably in combination with immunomodulators 2, 3
   • Evaluate response to anti-TNF therapy between 8-12 weeks 1

5. For maintenance after successful treatment:

   • Avoid long-term corticosteroids 5
   • Use thiopurines, methotrexate, or biologics for maintenance 1, 3